- CHAPTER 4 -
GRAZING LAND DEGRADATION
Edition 6, July 2007 (Updated December 2010)

- TABLE OF CONTENTS:

(4-A) -
Global Overview - [A1] General, [A2] Conversion of Cropland to Grazing land, [A3] Soil Erosion on Grazing Land, [A4]~Desertification, [A5] Soil Chemistry and Properties, [A6] Conversion of Grazing land to Cropland and Urban Land, [A7]~ Grazing Effects on Plant Species, [A8] Riparian Areas, [A9] Conversion of Forest Land to Grazing Land,
(4-B) - Grazing Land Degradation - Asia - [B1] Far East, [B2] Asian Sub-Continent, [B3] Middle East, [B4] Central Asia,
(4-C) - Africa - [C1] General, [C2] Northern Africa (Algeria, Egypt, Libya, Morocco, Tunisia), [C3]~ Eastern Africa (Ethiopia, Kenya (Nyasaland), Somalia, Sudan, Tanzania), [C4] Sahel (Burkina Faso, Chad, Gambia, Mali, Mauritania, Niger, Senegal), [C5]~ Southern Africa (Angola, Botswana, Lesotho, Madagascar, Mauritius, Mozambique, South Africa, Swaziland, Zimbabwe), [C6] Central Africa (Burundi, Central African Republic, Congo, Gabon, Malawi, Rwanda, Uganda, Zambia (Namibia)), [C7] Western Africa (Benin, Cameroon, Cape Verde, Cote D'Ivoire, (The) Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Nigeria, Sierra Leone),
(4-D) - North America - [D1] Western US in General, [D2] Desert Lands of North America, [D3]~ Riparian Areas, [D4] Forested Grasslands, [D5] BLM Lands, [D6] Far West, [D7] Interior Columbia Basin, [D8] Indian Reservation Range Land, [D9] Great Plains, [D10] Privately-owned Rangeland, [D11] State-Owned Rangeland, [D12] USFS Land, [D13] Great Basin, [D14] Water Runoff from Grazing Lands, [D15] Exotic Species Effects, [D16] Juniper, [D17] National Parks and Similar Lands,
(4-E) - South and Central America - [E1] General, [E2] South America, [E3] Central America,
(4-F) - Europe, Australia and Oceania - [F1] Australia, [F2] New Zealand, [F3] Europe,
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NOTE: The notation (su3) means that the data is used in the document analyzing the sustainability of the productivity of the world's food, fiber and water supply systems. (See elsewhere in this website.)

SECTION (4-A) - Global Overview of Grazing Land Degradation - [A1] General, [A2]~ Conversion of Cropland to Grazing land, [A3] Soil Erosion on Grazing Land, [A4] Desertification, [A5] Soil Chemistry and Properties, [A6] Conversion of Grazing land to Cropland and Urban Land, [A7] Grazing Effects on Plant Species, [A8] Riparian Areas, [A9] Conversion of Forest Land to Grazing Lands,

[A1] - Grazing Lands Degradation - General -

20% of the world's pastures are considered to be degraded through overgrazing, compaction and erosion (06U1). Comments: The term "pastures" probably excludes semi-arid and arid grasslands. These land categories tend to be far more degraded than the 20% figure would suggest.

Over-grazing accounts for 35% of total land degradation worldwide (96M1).

There is a growing consensus that the importance of overgrazing has been misjudged in the past, particularly in sub-Saharan Africa. This was in part caused by poor understanding of rangeland ecology, and in part by the lack of appreciation of traditional range management practices in arid and semi-arid areas (93B4). The alleged overgrazing in the Sahel, for example, is mainly a consequence of natural climate variability, i.e. low rainfall in some years, and poor stock management rather than overstocking per se (98F1) (03N1). Comments: A huge literature is in near-total agreement that the world's grazing lands are the most degraded lands on earth. The above statement is simply absurd. Even in the US, riparian habitats in the west have been largely obliterated, and they once provided the bulk of the rangeland productivity. Desertification is widely known to be largely an occurrence on grazed lands. Exotic species are diminishing rangeland productivities everywhere.

Ref. (96S3) highlight overgrazing in parts of the Caribbean and North Africa, and grazing of slopes in mid-altitude areas of Asia as areas of concern. Ref. (97U1) also lays emphasis on de-vegetation and land degradation from overgrazing (03N1). This is consistent with the detailed analysis of the impact of livestock on the environment given in Ref. (98D2) (03N1).

There has been some expansion of deserts and dryland degradation (92D3). Rapid rates of species loss, particularly of beneficial insects, birds and other predators may reduce the capacity for natural suppression of the pests, diseases and weeds that are among the greatest threats to current levels of agricultural production. However, quantification is not precise (92D3). The most extreme estimates suggest that 70% of the 36 million km2 of drylands are degraded, although this is likely to be an over-estimate. More probing analysis is highlighting the resilience and adaptability of crop and livestock systems in vulnerable areas such as the Sahel (93B4) (01M1) (03N1).

According to a 1991 UN assessment, (global) production losses from rangeland degradation accounts for $23 billion annually ($7 billion/ year in Africa. $8 billion/ year in Asia) (02E1).

In almost all developing countries fodder needs now exceed the sustainable yield of rangelands (02E1).

Degraded world rangeland now totals 6.8 million km2 (02E1). (la)

Degradation status of global land (croplands + permanent pasture + woodlands) based on work of Oldeman et al (Ref. 15 of (97C1)) and Dregne and Chou (Ref. 17 of (97C1)) (Land areas are in millions of km2) (la)
Category - - - - - -| Area |Lost Production
Total Land~ ~ ~ ~ ~ |87.35 | -
Not degraded~ ~ ~ ~ |67.70 | 0%
Lightly degraded~ ~ | 6.50 | 5%
Moderately degraded | 9.04 |18%
Strongly degraded ~ | 4.11 |50%
From the estimates above, one can calculate the weighted average loss for each land-use category: 10.9% for irrigated land, 12.9% for rain-fed cropland, and 43% for range land (97C1).

Asia has the largest area of degraded dryland, 3.7 million km2 (22%). Africa has 3.2 million km2 (25%) of degraded dryland and Europe has 1. million km2 ((97M3), p. 19). (la)

Overgrazing by livestock has caused as much as 20% of the world's pastures and range to lose productivity, which suggests that the global grass-eating livestock herd, now numbering 3.3 billion, is unlikely to increase much, if at all (91O1).

The cumulative productivity loss from soil degradation over the past 50 years has been roughly estimated using GLASOD data, to be about 13% for croplands and 4% for pasture lands ((98O1), p. 4) Comments: Rangeland degradation is probably a lot more, since rangeland is more arid, generally, than pastureland, and therefore more susceptible to degradation from overgrazing etc.

The great majority of rangelands where precipitation is 10-30 cm/ year have been moderately to severely over-grazed for 50+ years (85D1).

The UNEP Global Assessment of Soil Degradation Survey reveals that over 3 billion acres (12 million km2) (11% of the Earth's vegetated land) have been seriously degraded since 1945. Over-grazing by livestock accounts for 35% of this degraded land. Destructive agricultural practices account for 28% of global land degradation (92M1).

Rate of abandonment of drylands due to degradation: 90-110,000 km2/ year (Ref. 22 of (95D2)). Rates of degradation seem to be accelerating, particularly in developing countries (Ref. 23 of (95D2)).

The world's 3 billion ruminants (1 billion are beef cattle) are already overtaxing the Earth's grasslands, making it impossible for their numbers to continue to expand apace with human numbers. That "over-taxing" is the chief cause of the desertification that (says the UN) threatens 1/8 of the Earth's land surface (Ref. 82 of (82W1)).

"There are very few arid land areas today that are being grazed within their carrying capacity". - Jack D. Johnson, Director, Office of Arid-Land Studies, University of Arizona (Ref. 28 of (81S1)).

Fodder needs of livestock in nearly all developing countries now exceeds the sustainable yield of grassland and other forage resources (90B1).

Seiler and Crutzen (1980) estimate that 6 million km2/ year of savanna and grassland are burned, mostly in human-caused fires, and that the above-ground biomass in the herb-grass layer of the burned areas is 1.8-2.9 Gt. - half on natural grazing lands (86V2).

Losses in livestock production ($billion/ year) from land degradation in dryland regions (Ref. 11 of Chapter 6 of (94B3)(?))
Africa ~ |7.0|Asia ~ ~ |8.3|Australia| 7.5|Europe | 0.6
N.America|2.9|S.America|2.1|Total~ ~ |23.2|

Over-grazing since 1945 (million km2) (UNEP) (Ref. 22 of (94P1))
Asia ~ ~ ~ ~ |1.97|Africa |2.43|S. Amer.|0.68| -
N./Cent Amer.|0.38|Oceania|0.83|Europe~ |0.50|Total|6.79
Comments: Interpretation of this data is obscure.

Livestock produce drier soils by reducing plant- and litter cover (60E1), (91A3), compacting the soil (72L1) and reducing litter input into the soil (99G1).

An extensive review of the literature found no systematic investigations showing positive impacts or ecological benefits that could be attributed to livestock activities when grazed areas were compared to protected areas (99B1).

By reducing vegetative cover and disturbing the soil surface, livestock enhance wind and water erosion (60E1), (71L1), (88W1), ((98D1) in (99G1)).

Soil compaction reduces populations of soil decomposers, lowers hydrologic conductivity, aeration, and redox potential (88W1), (95B1), (98D1) in (99G1).

[A2] - Grazing Lands Degradation - Conversion of croplands to grazing lands -
Cultivation is expanding into rangeland that receives precipitation at 30-50 cm/ year. (Good grazing land is becoming poor cropland (85D1).) Since 1700, a steady reduction has occurred in the extent of the world's grazing lands. Over the past few centuries, tens of thousands of km2 of the world's great natural grasslands have been converted to croplands. More intensive mixed farming has pushed ranchers into the drier regions of poorer vegetation and soils - into the margins (Ref. 44 of (84R1)). Comments: Precipitation of 50 cm/ year is considered the minimum for dryland croplands. Less precipitation results in large amounts of wind erosion.

[A3] - Grazing Lands Degradation - Soil Erosion on Grazing Lands -

Grazing has repeatedly been shown to increase soil compaction and thus decrease water infiltration (See 8 references listed in Ref. (94F2)).

Ellison (60E1) concluded, "as a result of some degree of denudation, accelerated soil erosion is inseparably linked with overgrazing on arid lands the world over."

Numerous authors have noted extreme erosion and gullying when comparing heavily grazed to non-grazed sites (See list of 3 references in Ref. (94F2)).

Grazing reduces the roughness coefficients of watersheds, resulting in more surface runoff, more soil erosion and massive flooding (82O1).

GLASOD provides the only comprehensive information about soil loss for grasslands (91O2). It reports the world's "drylands" in the arid, semi-arid and dry sub-humid zones are particularly susceptible to soil degradation. These susceptible drylands constitute 55% of grasslands as defined by PAGE ((00W1), p.129). GLASOD found that slightly more than 10 million km2 of all susceptible grasslands globally have been degraded by human activity ((97M3), p.19). Water is the cause of 45% of this damage, and wind erosion 42% (00W2) ((97M3), p. 24).

Soil erosion rates may exceed 10,000 tonnes/ km2/ year in severely over-grazed pasture (Ref. 14 of (95P1)).

Over 50% of the world's pastureland are over-grazed and subject to erosive degradation (Ref. 15 of (95P1)).

[A4] - Grazing Lands Degradation - Desertification - [A4a] Extent, [A4b] Rate, [A4c] Russia, [A4d] China,

An estimated 6 million ha. (60,000 km2) of productive land is lost to desertification every year (UN data) (Rosamund McDougall, "Desertification and migration: An Optimum Population Trust Briefing," Optimum Population Trust, November 2006.) (su3) Comments: This loss apparently does not include losses of productive land to salt buildup in irrigation systems, to urbanization, and to cropland abandonment due to erosion. These add about 40,000 km2 additional land.

[A4a] - Desertification - Extent -

Desertification, the process by which productive dryland becomes wasteland, now affects 26 million km2 of rangeland, just over 60% of all rangeland area (98H1).

A Desertification Map of the world is in Ref. (81C1). The Earth's land areas are classified according to the extent of damage -"slight", "moderate", "severe" or "very severe" (from the 1977 UN Conference on Desertification).

80% of the world's grasslands are suffering from soil degradation, and 20% of the world's drylands are in danger of becoming deserts. (According to a UN report on global ecosystems released in 9/00. The $4 million study is the outcome of a program called Pilot Analysis of Global Ecosystems (PAGE)).

2.85 million km2 (36.8% of the continent's arid lands) have undergone "severe" desertification. 27,200 km2 of North America have undergone "very severe" desertification. 910,000 km2 within the US have experienced severe or very severe desertification (81S3).

Based on climatic data, more than a third of the Earth's land area is desert or semi-desert. Data on soil and vegetation indicate that 43% of the Earth's land surface is desert or semi-desert. The difference is accounted for by the estimated extent of man-made desert - 9.1 million km2 (81S1).

Total desertified dryland area: 36 million km2 (70% of global dryland area) (95D2). 26 million km2 of these desertified lands exhibit no soil degradation but have reduced crop yields, livestock forage and woody biomass for fuel and building material (Ref. 20 of (95D2)).

[A4b] - Desertification - Rates -

During the past 50 years, mankind has lost 1 million km2 to deserts (20,000 km2/ year) (76O1). Comments: Presumably this is just the "productive dryland".

Worldwide, over 23,000 square miles/ year becomes desert (Seattle-PI-Com Desertification, 11/23/99).

The global area of land with adequate water that has been degraded to near-desert conditions is larger than all of Brazil. The process claims 50-70,000 km2/ year (77B1). 60,000 km2 of new desert are formed annually by land mismanagement (compiled by WorldWatch Institute from various sources) (88B1).

In the 70 years, 1882-1952, deserts and wastelands increased from 9.4 to 23.3% of the Earth's total terrestrial area (Ehrlich and Ehrlich, 1972) (82O1).

Ref. (76S1) quotes Reid A. Bryson - "14 million acres (57,000 km2) of productive land are being lost yearly to desert encroachment".

Desertification claims 60,000 km2/ year. An additional 200,000 km2 become too debilitated to support profitable farming and grazing (89P1) (89P2).

Over 40% of the particulate load of the world's rivers is carried by highly turbid waters - waters draining arid- and semi-arid regions (82M2). Comments: Arid and semi-arid lands are predominantly grazing lands rather that croplands. In the US, rivers draining regions of grazing lands have sediment loads per unit area of drainage basin that are several times the national average.

Reductions in land productivity by as much as 90% were reported for several areas during the 1977 UN Conference on Desertification (Ref. 23 of (81C2)).

During the past 50 years, mankind has lost 1 million km2 to deserts (20,000 km2/ year) (76O1). Comments: Presumably this is just the "productive dryland".

Worldwide, over 23,000 square miles/ year becomes desert (Seattle-PI-Com Desertification, 11/23/99).

The global area of land with adequate water that has been degraded to near-desert conditions is larger than all of Brazil. The process claims 50-70,000 km2/ year (77B1). 60,000 km2 of new desert are formed annually by land mismanagement (compiled by WorldWatch Institute from various sources) (88B1).

In the 70 years, 1882-1952, deserts and wastelands increased from 9.4 to 23.3% of the Earth's total terrestrial area (Ehrlich and Ehrlich, 1972) (82O1).

Ref. (76S1) quotes Reid A. Bryson - "14 million acres (57,000 km2) of productive land are being lost yearly to desert encroachment".

Desertification claims 60,000 km2/ year. An additional 200,000 km2 become too debilitated to support profitable farming and grazing (89P1) (89P2).

Over 40% of the particulate load of the world's rivers is carried by highly turbid waters - waters draining arid- and semi-arid regions (82M2). Comments: Arid and semi-arid lands are predominantly grazing lands rather that croplands. In the US, rivers draining regions of grazing lands have sediment loads per unit area of drainage basin that are several times the national average.

Reductions in land productivity by as much as 90% were reported for several areas during the 1977 UN Conference on Desertification (Ref. 23 of (81C2)).

[A4c] - Desertification - Russia -

Desertification extent in Russia (as of 1993) (03Z1).
- - - -|% of soil| Causative factors (km2)
Extent | mapping |Cultiv-| Over-~ |Indust-
(km2)~ | unit~ ~ |ation~ | grazing| rial
357,000| ~ 2.14% | 2000~ | 354,000| 2000

The indicated extent of desertification in Russia is in line with previous studies (Stolbovoi and Fischer, 1999). According to the latest estimates, the area (of Russia) affected by desertification is currently (2003) about 1 million km2 (03Z1). Comments: This is surprising - an increase in desertified area of about 650,000 km2 just during the period 1993-2003. This figure should probably be regarded with some suspicion due to its large size - although Russia has a very large land area, and so much of this land has been badly degraded over the centuries.

Evidences of Russian desertification are found in the Astrakhan, Volgograd, and Rostov oblasts; the Altai Krai, and the Republics of Tuva and Dagestan. Small areas of Krasnodar and Stavropol Krais have also been affected. Territories under threat of desertification include land in the southern part of the steppe zone in the Voronezh, Saratov, Orenburg, Omsk, Chelyabinsk, and Chita regions, and in the Republics of Khakasia and Buryatia (03Z1). However the most alarming situation is found in Kalmyk Republic, which is the most arid region of the European part of Russia. More than 80% of Kalmyk is in the grip of desertification, with almost half of it being either severely or very severely affected (03Z1).

[A4d] - Desertification - China -

China's old deserts are advancing and new ones are forming. Desert expansion has accelerated with each successive decade since 1950. China's Environmental Protection Agency reports that the Gobi Desert expanded by 52,400 km2 (20,240 square miles) from 1994-99. The advancing Gobi is now within 150 miles of Beijing (03B1).

Over-plowing and overgrazing in China are converging to create a dust bowl of historic dimensions. With little vegetation remaining in parts of northern and western China, the strong winds of late winter and early spring can remove millions of tons of topsoil in a single day. On 4/12/02, for instance, South Korea was engulfed by a huge dust storm from China that left people in Seoul literally gasping for breath. Schools were closed, airline flights were cancelled, and clinics were overrun with patients having difficulty breathing. Koreans have come to dread the arrival of what they now call "the fifth season" - the dust storms of late winter and early spring. Japan also suffers from dust storms originating in China (03B1).

A report by a US embassy official in May 2001 after a visit to Xilingol Prefecture in Inner Mongolia (Nei Mongol) notes that although 97% of the region is officially classified as grasslands, a third of the terrain now appears to be desert. The report says the prefecture's livestock population climbed from 2 million as recently as 1977 to 18 million in 2000. A Chinese scientist doing grassland research in the prefecture says that if recent desertification trends continue, Xilingol will be uninhabitable in 15 years. Satellite images show two deserts in north-central China expanding and merging to form a single, larger desert overlapping Inner Mongolia and Gansu provinces. To the west in China's Xinjiang Province, two even larger deserts -Taklimakan and Kumtag - are also heading for a merger (03B1).

A human population of 1.3 billion and a livestock population of just over 400 million are weighing heavily on China's land. Huge flocks of sheep and goats in the northwest are stripping the land of its protective vegetation, creating a dust bowl on a scale not seen before. While over-plowing is now being partly remedied by paying farmers to plant their grain-land in trees, overgrazing continues largely unabated. China's cattle, sheep, and goat population tripled from 1950 to 2002. The US, a country with comparable grazing capacity, has 97 million cattle. China has 106 million. But for sheep and goats, the figures are 8 million (US) versus 298 million (China). (See data at http://www.earth-policy.org/Updates/Update26_data.htm) (03B1).

Millions of rural Chinese may be uprooted. Expanding deserts are driving villagers from their homes in Gansu, Inner Mongolia, and Ningxia provinces. An Asian Development Bank assessment of desertification in Gansu Province reports that 4,000 villages risk being overrun by drifting sands. The US Dust Bowl of the 1930s forced some 2.5 million "Okies" to leave the land, many of them heading from Oklahoma, Texas, and Kansas to California. But the dust bowl forming in China is much larger, and during the 1930s the US population was only 150 million - compared with 1.3 billion in China today. Whereas the US "Okie" migration was measured in the millions, China's may eventually measure in the tens of millions (03B1).

Beijing is trying to arrest the spread of deserts by encouraging pastoralists to reduce their flocks of sheep and goats by 40%. The chairman of China's Environment and Resources Committee of the National People's Congress, estimates that remediation of land in the areas, where technically feasible, would cost $28.3 billion (03B1).

[A5] - Grazing Lands Degradation - Soil Chemistry and Properties -

The 4/2000 issue of Rangelands contains an article on Dutchwoman Butte (DB) on Tonto National Forest in Arizona. The area had never been grazed, making it extremely rare. The authors compared Dutchwoman Butte with a near-by grazed allotment with the same elevation, precipitation, soil type, etc. (and which the USFS declared to be in good condition). It was found that bulk soil density on the grazed site was24% higher than on DB. The authors noted that a 15% increase in bulk density decreases water infiltration by 50%. (Also see Section 4-A [7] for effects on plant species.)

More than 100+ years of (US) livestock grazing has resulted in serious depletion in nitrogen stores in the soils (due to destruction of the microbiotic crust, losses of nitrogen from volatilization from urine and manure, consumption of nitrogen (in plant leaves) by livestock that are taken away to stockyards, and increases of de-nitrification due to soil disturbance). Additional losses of nitrogen from shrub- and juniper-burning programs may push extensive plant communities over "thresholds" into new and permanently degraded stable states (97B3).

[A6] - Grazing Lands Degradation - Conversions of Grazing Land to Cropland and Urban Land -

The Esquel Foundation found that, between 1977 and 1994, the planted area of foodstuff production increased by 25% in Brazil's semi-arid lands (937,000 km2 total area). The region's average rate of reduction of agricultural productivity of foods (tonnes/ ha) is 2-3%/ year (2.6%/ year between 1977 and 1994) (Marco Bahe, "Brazil loses US$800 million/ year with desertification," Brazil-Arab News Agency, 6/13/06.).

About 4000 km2 of China's arable land have been lost to urban sprawl over the past decade (06P1).

The original grasslands of Asia, Africa and Australia each retain at least 60% of the area in grasslands, with fewer than 20% in croplands and fewer than 2% in urban or built-up areas ((00W1), p. 122).

Croplands cover 71% of the original Tallgrass prairie in North America, and urban areas cover 19% (See table below) ((00W1), p. 122). Comments: The large conversion to urban areas seems suspect, since this would imply a massive area converted to urban use.

Conversions of Original Grasslands ((00W1), p.123) (la)
Region- - - - - - - -|Remaining|To ~ |To
- - - - - - - - - - - - | Grass|Crop |Urban
- - - - - - - - - - - - | -Land|Land |Areas
Tallgrass Prairie (US)- | ~9.4%|71.2%|18.7%
Cerrado Woodland/Savanna| 21.0 |71.0 | 5.0%
(Brazil/ Paraguay/ Bolivia)
Daurian Steppe~ ~ ~ ~ ~ | 71.7 |19.9 | 1.5%
(Mongolia/ Russia/ China)
Central/East. Mopane and| 73.3 |19.1 | 0.4%
Miombo Woodlands (Tanzania/ Rwanda/ Burundi/ Dem. Rep./ Congo/ Zambia/ Mozambique)
SW Australia shrublands | 56.7 |37.2 | 1.8%
and woodlands

[A7] - Grazing Lands Degradation - Grazing Effects on Plant Species -

In numerous studies, grazing has been correlated with the loss of microbiotic cover (94F2) (81J1) (82A2) (87J2).

The 4/00 issue of Rangelands contains an article on Dutchwoman Butte (DB) on Tonto National Forest in Arizona. The area had never been grazed, making it extremely rare. The authors compared Dutchwoman Butte with a near-by grazed allotment with the same elevation, precipitation, soil type, etc. (and which the USFS declared to be in good condition).

[A8] - Grazing Lands Degradation - Riparian Areas -

Ref. (94F2) reviews the literature on the rate of recovery of riparian habitats following cessation of grazing. In general, the moister parts appear able to recover in a few years, whereas the drier peripheries take well over a decade.

[A9] - Grazing Lands Degradation - Conversion of Forest Land to Grazing Land -
NOTE: There is a lot more data on this issue in the review of global literature on forestland degradation.

Some 70% of former forests in the Amazon basin have been converted to grazing lands (06U1).

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SECTION (4-B) - Grazing Land Degradation - Asia - [B1] Far East, [B2] Asian Sub-Continent, [B3] Middle East, [B4]~ Central Asia,

[B1] - Grazing Lands Degradation - Asia - Far East -

Wang Tao, one of the world's leading desert scholars, reports that from 1950 to 1975 an average of 600 square miles turned to desert each year in China. By 2000, nearly 1,400 square miles 3,600 km2 were going to desert annually. Over the last half-century, some 24,000 villages in northern and western China have been entirely or partly abandoned as a result of being overrun by drifting sand (10B1).

While the US, a country with comparable grazing capacity, has 97 million cattle, China has a slightly smaller cattle herd of 82 million. But while the US has only 9 million sheep and goats, China has 284 million (10B1).

China is being affected by desertification more than any other major country. The Cold and Arid Regions Environmental and Engineering Research Institute, describes China's accelerating desertification. From 1950-75 China lost an average of 1560 km2 of land to desert each year. Between 1975-87, this climbed to 2100 km2/ year. From then until 2000, it jumped to 3600 km2 of land degrading to desert annually. Over the last half-century, some 24,000 villages in northern and western China have been entirely or partly abandoned as a result of being overrun by drifting sand (06B1). (su3\)

On April 18, 2001, the western US - from the Arizona border north to Canada - was blanketed with dust. It came from a huge dust storm that originated in northwestern China and Mongolia on April 5. Measuring 1800 km. across when it left China, the storm carried millions of tons of topsoil. On April 12, 2002, South Korea was engulfed by a huge dust storm from China that left people in Seoul literally gasping for breath. Schools were closed, airline flights were cancelled, and clinics were overrun with patients having difficulty breathing. Koreans have come to dread the arrival of what they now call "the fifth season," the dust storms of late winter and early spring. These two dust storms, among the 10 or so major dust storms that occur each year in China, are one of the externally visible indicators of the ecological catastrophe unfolding in northern and western China. Overgrazing on arid lands is the principal cause of dust storms (06B1).

A US Embassy report entitled "Desert Mergers and Acquisitions" describes satellite images showing two deserts in north-central China expanding and merging to form a single, larger desert overlapping Inner Mongolia and Gansu provinces. To the west in China's Xinjiang Province, two even larger deserts - the Taklimakan and Kumtag - are also heading for a merger. Highways running through the shrinking regions between the deserts are regularly inundated by sand dunes (06B1).

About 25% of China's land mass is composed of deserts (06P1).

Expanding deserts swallow about 4000 km2 of land in China (06P1). (su3)

China's EPA said that soon 40% of China could turn into scrubland, creating massive social, economic and ecological challenges (06P1).

About 4000 Chinese villages have been entirely swallowed by encroaching desert (06P1).

The Gobi Desert in central China has expanded by about 65,000 km2 since 1994, and its sands are now within 100 miles of Beijing (06P1).

China is not only losing productive land to deserts, but it is doing so at an accelerating rate. From 1950-75 China lost 600 square miles of land (1560 km2) to desert each year. By 2000, nearly 1400 square miles were going to desert annually. A US Embassy report entitled "Desert Mergers and Acquisitions" describes satellite images that show two deserts in north-central China expanding and merging to form a single, larger desert overlapping Inner Mongolia and Gansu provinces. To the west in Xinjiang Province, two even larger deserts - the Taklimakan and Kumtag - are also heading for a merger (06B2). The Gobi Desert has moved to within 150 miles (241 km) of Beijing (06B2). Over the last half-century, 24,000 villages in northern and western China were abandoned or partly depopulated as they were overrun by drifting sand (06B2).

[B1a] - Grazing Lands Degradation - Far East - China -

After the 1978 economic reforms, when China shifted to a market economy, the government lost control of livestock numbers. Livestock populations then grew rapidly, to numbers far exceeding those in the US, a country with comparable grazing capacity. E.g.
Cattle: US - 97 million: China - 128 million.
Sheep/ goats: US - 8 million: China - 290 million (Comments: Sheep and goats are better suited to degraded grassland because their teeth can cut grass closer to the soil. ) (
UNFAO, FAOSTAT Statistics database at www.aps/fao.org 5/28/02)

In Gonge County (eastern Qinghai Province of northwestern China) the number of sheep that the local grassland can support is estimated at 3.7 million. At the end of 1998 the region's flock had reached 5.5 million (Eric Eckholm, "Chinese Farmers See a New Desert Erode their Way of Life", New York Times, 7/30/00).

From the mid-1990s to 2000, 1374 square miles (3559 km2) of China (?) have turned into desert each year (vs. 840 square miles (2180 km2) per year in the 1980s, and 624 square miles (1616 km2)/ year during the 1970s (04H1). Comments: Does this refer to China or to the world?

China has lost 36,000 square miles of land to desert since the 1950s (04H1).

28% of China's land mass has been overtaken by desert, with 18% being decimated by effects of overgrazing and deforestation (China Daily reports, 1/31/02).

Spreading deserts are also displacing people. In China, where the Gobi Desert is growing by 10,400 square kilometers (4,000 square miles) a year, the refugee stream is swelling. Chinese scientists report that there are now desert refugees in three provinces - Inner Mongolia, Ningxia, and Gansu. An Asian Development Bank preliminary assessment of desertification in Gansu Province has identified 4000 villages that face abandonment (Lester R. Brown, "Troubling New Flows of Environmental Refugees", Earth Policy Institute, 1/28/04).

China is planting 26 million acres, 10% of its grain-growing area, with trees. But many die because the soil is already too thin (03L1).

In China's Ganzu province 4,000 villages are facing being submerged by drifting sands. The Earth Policy Institute believes that, throughout China, tens of millions of people may be forced off their land, dwarfing the migrations of "Okies" from America's dust bowl (03L1).

Between 1994-99, China's Environmental Protection Agency reports, the Gobi Desert expanded by 20,240 square miles (52,400 km2), to within 150 miles of Beijing. New areas of desert are erupting all over China. Desertification is affecting 40% of China's land. Partly as a result, harvests, which more than quadrupled between 1950-98, have fallen sharply, even as China's population and appetite grow (03L1).

Dust storms have been recorded in China for at least 2,700 years, but they are now increasing in size and number. The Chinese Meteorological Agency says there were 5 major storms in China in the whole of the 1950s. This rose to 23 in the 1990s. But the first two years of this decade have almost equaled this figure already, with 20 (03L1). They have even occasionally crossed the Pacific: one in April 2001 covered the west of North America from Canada to Arizona with dust (03L1).

Growing livestock populations are changing 900 square miles of China to desert/ year ("Dust Bowl Threatening China's Future", earth-policy.org, 4/18/01).

In addition to the direct damage from over-plowing and overgrazing, the northern half of China is literally drying out as rainfall declines and over-pumping depletes aquifers. Water tables are falling almost everywhere, altering the region's hydrology. Thousands of lakes in northern China have disappeared (US satellite data over 30 years) (01B2).

In the New York Times, Beijing Bureau Chief Erik Eckholm writes that "the rising sands are part of a new desert forming on the eastern edge of the Quinghai-Tibet Plateau, a legendary stretch once known for grass reaching as high as a horse's belly and home for centuries to ethnic Tibetan herders." Official estimates show 900 square miles (2330 km2) of land on the eastern edge of the Quinghai-Tibet Plateau going to desert each year. An area several times as large is suffering a decline in productivity as it is degraded by overuse (01B2).

In Gonge County in eastern Quinghai Province of China, the number of sheep that local grasslands can sustain is estimated at 3.7 million, but by the end of 1998, sheep numbers there had reached 5.5 million (01B2).

On 4/18/01, scientists at the National Oceanic and Atmospheric Administration (NOAA) laboratory in Boulder, Colorado, reported that a huge dust storm from northern China had reached the US "blanketing areas from Canada to Arizona with a layer of dust." They reported that along the foothills of the Rockies the dust from China obscured the mountains. On 3/10/01, The People's Daily reported that the season's first dust storm-one of the earliest on record-had hit Beijing. These dust storms, coupled with those of 2000, were among the worst in memory, signaling widespread deterioration of rangeland and cropland in China's northwest (01B2). These huge dust plumes routinely travel hundreds of miles to populous cities in northeastern China, including Beijing, obscuring the sun, reducing visibility, slowing traffic, and closing airports. Reports of residents in eastern cities caulking windows with old rags to keep out the dust are reminiscent of the US dust bowl of the 1930s. Eastward moving winds often carry soil from China's northwest to North Korea, South Korea, and Japan, countries that regularly complain about dust clouds that both filter out the sunlight and cover everything with dust (01B2). (Continued below)

In addition to local pressures on resources, a decision in Beijing in 1994 to require that all cropland used for construction be offset by land reclaimed elsewhere. This policy has helped create the ecological disasters (dust storms) that are now unfolding. In an article in Land Use Policy, Chinese geographers Hong Yang and Xiubein Li describe the environmental effects of this offset policy. The fast-growing coastal provinces, such as Guandong, Shandong, Xheijiang, and Jiangsu, which are losing cropland to urban expansion and industrial construction, are paying other provinces to plow new land to offset their losses. This provided an initial economic windfall for provinces in the northwest, such as Inner Mongolia (which led the way with a 22% cropland expansion), Gansu, Qinghai, Ningxia, and Xinjiang (01B2).

In Seoul, South Korea, for the third consecutive year, huge clouds of dust have blown in from China's deserts 750 miles away. Consequently, Seoul's residents have suffered breathing problems, school closures, cancelled domestic flights, workplace absenteeism, and dipping retail sales. 70 micrograms of dust/ m3 of air is normal for Seoul, but a recently a record measurement of 2,070 micrograms was reported. The dust is a result of the rapid desertification in China and a prolonged drought affecting China and other parts of Northeast Asia. Tokyo has also seen an unusually dusty spring. Particles of the airborne sand now travel 7,000 miles to Portland, Ore., and San Francisco, by riding the jet stream ("China's Growing Deserts Are Suffocating Korea", New York Times, 4/12/02).

In Gonge County in eastern Qinghai Province (northwestern China) an estimated 3.7 million sheep can be supported locally, yet by the end of 1998, the region's flock had reached 5.5 million (02E1).

A 2001 survey conducted by China's State Forestry Administration says 28% of China's land mass has been overtaken by desert, with 18% being decimated by effects of overgrazing and deforestation (China Daily reports, 1/31/02.).

After centuries of nomadic grazing, sedentary grazing predominates in China. Native rangelands are deteriorating. In many areas, over-grazing has led to loss of climax species, plant vigor and production. China's grassland (steppe range or pasture) occupies 3.6 million km2 -37.1% of China's land area (82B1).

China loses 1200 km2/ year of farm- and pasture land to drifting sand dunes (86W1). Comments: Losses to urbanization are several times larger (See soils Review).

Over 33% of China's rangelands are over-grazed (93L1), (96M1). Comments: This seems low, but it is higher than 1989 (23%).

Over-grazing affects 510,000 km2 (23% of China's total grassland). Biomass productivity has dropped 30-50% since the 1960's (89C1).

China has launched an emergency program to fight desertification after a large number (12) of deadly dust storms in northern China in early 2000. Xinhua said the program aimed to check the rapid expansion of 3 deserts in Inner Mongolia, including one 180 km. from the capital (South China Morning Post, 5/24/00).

15.6 million people and 13.1 million farm animals face water shortages in China. China plans to turn 5 million km2 of land at the fringe of the deserts into grassland by 2010 and aims to have the problem under control by 2050. Much of the problem is due to over-grazing and illegal logging. Deserts now cover 2.62 million km2, or 27% of China (South China Morning Post, 5/24/00). Comments: The "5 million" figure is suspect, since total land area of China is 9.33 million km2.

In northern China over 900 square miles (2330 km2/ year) of land turn into desert, due mainly to excessive grazing and logging (Daily Grist, 7/31/00).

[B1b] - Grazing Lands Degradation - Far East - Mongolia -

Studies in Buryatia and Chita Oblast in Russia (just north and northeast of Mongolia) and in Inner Mongolia in China (just south and east of Mongolia suggest that as much as 75% of grasslands have suffered some degree of degradation. ((99H1),p. 52) ((96G1),p. 21) Chinese government figures say 44% of Inner Mongolia's grasslands are useable and in good condition ((99N1),p. 426).

The yield of forage from Inner Mongolia's rangelands has declined by at least 30%, and as much as 70%, over the past half-century. If trends continue, Xilingol will be uninhabitable in 15 years ("Grapes of Wrath in Inner Mongolia", report from US Embassy in Beijing, May 2001).

In Mongolia's grasslands, moderate or severe degradation affects 4-20% of pasturelands. (95G2), p. 28) Comments: The far better condition of Mongolia's grasslands relative to those of adjacent Inner Mongolia, Buryatia and Chita Oblast are attributed by Ref. (00W1) to Mongolia's mobile herding practices vs. the more stationary (sedentary) practices found in grasslands of Mongolia's neighbors.

[B2] - Grazing Lands Degradation - Asian Sub-Continent -

The woody biomass of Pakistan is now threatened by the growing consumption of fuel wood and timber. It is feared that this natural resource will be totally consumed within the next 15 years, says a government report on deforestation. The principal cause of deforestation in Pakistan is the consumption of fuel wood and timber (primarily for household firewood). Consumption exceeds growth in all the four provinces except in the relatively sparsely populated Northern Areas. Consumption is expected to increase in line with the growth of population projected at 3%/ year. Pakistan has the world's second highest rate of deforestation. The deforestation has been attributed to rapid population growth, illegal logging, unsustainable use of natural resources and minimal participation in reforestation programs. Deforestation is also a combination of governmental mismanagement, corruption and economic development, says a related report. (Continued below.)

The moratorium on timber harvesting in Pakistan following the 1992 floods has not been effective. Further, the moratorium has reportedly resulted in increased timber smuggling from Afghanistan. As most of this wood is extracted by clear-cutting of forests in Kunar province, and as these forests fall within the watershed of the Kabul River, the adverse impacts of deforestation in Afghanistan will be felt down stream in Pakistan. Pakistan's biodiversity action plan states the principal direct cause of degradation of Pakistan's rangelands and forests is the rapidly increasing domestic livestock population. Between 1945-86, the number of cattle in Pakistan almost doubled; the number of buffaloes, sheep and goats more than tripled. Overall livestock numbers continue to increase at 2%/ year. While much of this increase has been fed by the production of fodder within irrigated areas, persistent overgrazing has reduced forage production in Pakistan's rangelands to one-third the potential (a loss of almost 50 million tonnes/ year), and in some areas to as low as 15% of potential forage production. The problem is particularly acute in Balochistan ("Pakistan Rangelands Degradation," The Peninsula - Qatar's Leading English Language Daily Web posted 6/3/2006.). (su3)

[B2a] - Grazing Lands Degradation - Asian Sub-Continent -India -

In India, demand for fodder in 2000 was estimated at 700 million tons, vs. a sustainable supply of 540 million tons (Lester R. Brown, Eco-Economy, W. W. Norton and Co., New York (2001) p. 61).

In India, demand for fodder in 2000 was estimated at 700 million tons, but only 540 million tons could be supplied sustainably (02E1).

Studies by the Indian Planning Commission concluded that India's Thar Desert has been spreading for the past 50 years at 130 km2/ year (76E1).

Great Thar Desert (Northwest India) does not have a truly arid climate, but has been turned into a barren wasteland, mostly by over-grazing. (Great Thar Desert turns truly arid in Pakistan (4-8" of precipitation/ year).) (p. 359 of (91J1)).

In the Indian states of Rajasthan and Karnataka, fodder supplies 50-80% of needs, leaving large numbers of emaciated cattle (90B1).

In the grazing land of one district of the central Himalayas in India, livestock populations exceed the carrying capacity of the land by a factor of 4.5 (Environment, 29(3) (1987) p. 11).

[B3] - Grazing Lands Degradation - Middle East -

In Afghanistan the Registan Desert is migrating westward, encroaching on agricultural areas. A U.N. Environment Program (UNEP) team reports "up to 100 villages have been submerged by windblown dust and sand." In northwest Afghanistan, sand dunes are moving onto agricultural land in the upper reaches of the Amu Darya basin, their path cleared by the loss of stabilizing vegetation due to firewood gathering and overgrazing. The UNEP team observed sand dunes 15 meters high blocking roads (10B1).

In the southeastern province of Sistan-Balochistan in Iran, sand storms have buried 124 villages and their grazing areas, forcing their abandonment (10B1).

Iran's Anti-Desertification Organization reported in 2002 that sand storms had buried 124 villages in Iran's southeastern province of Sistan-Baluchistan, forcing their abandonment. Drifting sands had covered grazing areas, starving livestock and depriving villagers of their livelihood (06B1).

Afghanistan's Registan Desert is migrating westward, encroaching on agricultural areas. A UN Environment Program (UNEP) team reports "up to 100 villages in Afghanistan have been submerged by windblown dust and sand." In Afghanistan's northwest, sand dunes are moving onto agricultural land in the upper reaches of the Amu Darya basin, their path cleared by the loss of stabilizing vegetation from firewood gathering and overgrazing. The UNEP team observed sand dunes 15 meters high blocking roads (06B1).

In Afghanistan (population 31 million), the Registan Desert is migrating westward, encroaching on agricultural areas. A UN Environment Program (UNEP) team reports, "up to 100 villages have been submerged by windblown dust and sand (06B2)." In Afghanistan's northwest, sand dunes are moving onto agricultural lands that have been degraded by firewood gathering and overgrazing (06B2).

Iran (70 million people + 80 million goats and sheep), is also losing its battle with the desert. In 2002 sand storms buried 124 villages in the southeastern province of Sistan-Baluchistan, forcing abandonment (06B2).

In 13 of 15 Arab Nation States over-grazing accounts for more than 35% of land degradation. For 7 of the 17 Arab Nation states overgrazing accounts for at least 75% of land degradation, with Saudi Arabia, Libya and Jordan at the top of the list (96M1).

Plant cover has disappeared in many steppe zones in Syria, Jordan, Iraq, the U.A.R. and Iran. Rangelands there have become semi-deserts of gravel or semi-sand (81B1).

[B3a] - Grazing Lands Degradation - Middle East - Iran -

In Iran, villages abandoned because of spreading deserts and a lack of water already number in the thousands. In the eastern provinces of Baluchistan and Sistan alone, some 124 villages have been buried by drifting sand. In the vicinity of Damavand, a small town within an hour's drive of Tehran, 88 villages have been abandoned (Lester R. Brown, "Troubling New Flows of Environmental Refugees", Earth Policy Institute, 1/28/04).

Rangelands had deteriorated 33-50% by 1970. Says Niknam's estimate of 4 times over-stocking in 1970 is conservative. 1,000,000 km2 of rangeland in Iran carried 84 million sheep units in 1970. Carrying capacity in 1970: 21 million sheep units (78K1).

Forests cover 180,000 km2 (11%) of Iran's 1,650,000 km2. Ranges that were once forest total 100,000 km2 (6.1%). 410,000 km2 of desert wasteland furnishes little, if any, forage. Herbaceous cover is over-grazed and depleted nearly everywhere. Topsoil, sometimes shallow over rocky subsoil, has gone from large tracts of once forested lands (74S1).

[B3b] - Grazing Lands Degradation - Middle East - Iraq -

A UN report on the Middle East in the fall of 1977 reported that the natural range lands in the north of Iraq are able to support 250,000 sheep, but contain 4 times that many (78B1) (81B1).

[B3c] - Grazing Lands Degradation - Middle East - Syria -

A UN report on the Middle East in the fall of 1977 reported that the arid- and semi-arid natural rangeland zones in Syria contain three times the amount of livestock that can be sustained (78B1) (81B1).

The revival of the ancient "Hema" system of land management controls the number of sheep a family may graze on the range. By reducing over-grazing, the system has enabled the revegetation of 69,000 km2 of rangeland in Syria (89P1).

[B4] - Grazing Lands Degradation - Central Asia - 

The second major expansion came in the Soviet Union beginning in the mid-1950s. In an all-out effort to expand grain production, the Soviets plowed an area of grassland larger than the wheat area of Australia and Canada combined. The result, as Soviet agronomists had predicted, was an ecological disaster - another Dust Bowl. Kazakhstan, where the plowing was concentrated, has abandoned 40% of its grain land since 1980. On the remaining cultivated land, the wheat yield per acre is one sixth of that in France, Western Europe's leading wheat producer (10B1).

All the countries in central Asia - Afghanistan, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan - are losing land to desertification. Kazakhstan, site of the vast Soviet Virgin Lands Project, has abandoned nearly half of its cropland since 1980 (06B2).

[B4a] - Grazing Lands Degradation - Central Asia - Russia -

Southern Russia's Kalmykia Desert spreads by 400 km2/ year. Since 1954 it has grown from 120 to over 8100 km2 (92F1).

Desertification of the unique pastures of the Black Lands of Kalmykia (in Russia) has led to the first man-made desert in Europe, with areas of open and blown sand. Satellite imageries confirm that large amounts of sand are blown out of this area during dust storms, reaching the borders of European countries beyond Russia. Man-made desert in Europe has expanded by about 10,000 km2. (Comments: Presumably since the start of human settlement.) The crisis resulted from intensive land degradation and a shortage of water, together with the increasing human load on the natural environment over the last few decades and extreme natural conditions, which caused a decline in the health of the population and decreases in both life expectancy and quality of life (03Z1).

In Kalmykia in Russia's semi-desert zone, moderately and greatly trampled pastures make up 66% of pastureland. The productivity of trampled pastures is 3-5 times less than that of pastures under moderate grazing (03S1).

Dry meadows in the forest zone of European Russia: Productivity has sharply decreased on meadows that have been flooded for a short time (1935, 1.5 tonnes/ ha; 2000, 1.0 tonnes/ ha) and on meadows flooded for a long time (1935, 2.4 tonnes/ ha; 2000, 1.5 tonnes/ ha DM). Areas with a valuable fertile herbage (foxtails, timothy, bromes, tall grasses and herbs) on dry, low-lying, and bog meadows in Russia have shrunk by 5-10 times (03S1).

Forage reserves of lichens in Russia have shrunk by 2-3 times in reindeer pastures since 1950 (03S1).

The degradation of Russia's pastures and hayfields is constantly increasing and hayfield areas are shrinking (03S1). Between 1986-90, about 24 million tonnes of hay were harvested annually, vs. 17.7 million tonnes in 2000 (03S1).

The productivity of Russia's pastures and hayfields is constantly decreasing. Currently, it is 0.7-1.0 tons (tonnes)/ha of green mass for hayfields and 200-400 tonnes/ km2/ year for pastures. Low productivity can be explained by the fact that 70% of these degraded lands, which are covered with shrubs, low forests, tussocks and swamps, are located on saline soils and solonetz complexes. More than 50% of Russia's hayfields and pastures require improvement (03S1).

SECTION (4-C) - Grazing Land Degradation -Africa - [C1] General, [C2] Northern Africa (Algeria, Egypt, Libya, Morocco, Tunisia), [C3] Eastern Africa (Ethiopia, Kenya (Nyasaland), Somalia, Sudan, Tanzania), [C4] Sahel (Burkina Faso, Chad, Gambia, Mali, Mauritania, Niger, Senegal), [C5] Southern Africa (Angola, Botswana, Lesotho, Madagascar, Mauritius, Mozambique, South Africa, Swaziland, Zimbabwe), [C6] Central Africa (Burundi, Central African Republic, Congo, Gabon, Malawi, Rwanda, Uganda, Zambia (Namibia)), [C7] Western Africa (Benin, Cameroon, Cape Verde, Cote D'Ivoire, (The) Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Nigeria, Sierra Leone),

[C1] - Grazing Lands Degradation - Africa - General -

The annual addition of 17 million people and over 5 million cattle, sheep, goats is degrading land and undermining economic progress in Africa (Ref. 5 of (88B2)).

10 million km2 of Africa have undergone "severe" desertification; 14,200 km2 have undergone "very severe" desertification (Ref. 9 of (81S1)).

[C2] - Grazing Lands Degradation - Northern Africa (Algeria, Egypt, Libya, Morocco, Tunisia) -

In northern Africa, the Sahara Desert is pushing the populations of Morocco, Tunisia, and Algeria northward. On the southern edge of the Sahara, in the east-to-west swath of semiarid Africa between the Sahara Desert and the forested regions to the south lies the Sahel - a semiarid region where herding and farming overlap. In countries from Senegal and Mauritania in the west to Sudan, Ethiopia, and Somalia in the east, the demands of growing human and livestock numbers are converting land into desert (06B2). (See data at www.earthpolicy.org/Updates/2006/Update61_data.htm.)

LeHoverou's study of the desertification of Mediterranean steppe bordering the northern Sahara in Libya, Tunisia and Algeria describes the process as being composed of reduction of perennial plant cover, impoverishment of flora, soil erosion, formation of mobile sand dunes and establishment of desert pavement (gravel and scree). LeHoverou attributes the initiation of the process to over-grazing by livestock, cereal cultivation, cutting of wood species and other aspects of mismanagement of natural vegetation (70K1).

In Tunisia, Algeria and Morocco, rangelands are populated by three head of cattle where only one could thrive (UN report) (p. 362 of Ref. (91J1)).

Morocco, Algeria, Tunisia and Libya have lost grazing land and croplands to desert at a rate of over 1000 km2/ year (Ref. 8 of Ref. (78E1)). Comments: This presumably means in total.

The evolution of vegetation on Algeria-Tunisia's high plains is shown schematically in Ref. (70L1). Vegetation in the arid zone of North Africa has experienced accelerated deterioration since around 1930. This deterioration results from the great population pressure (intense over-grazing), the extension of episodic cereal-growing, and the removal of woody species for firewood (1 kg/ person/ day = 0.5-1.0 ha. of woody vegetation/ person/ year (70L1). Climate change is not a cause (70L1).

Desertization (irreversible land degradation in 5-20-cm. rainfall zone) has been causing desert expansion on both sides of the Sahara and the Near East at 0.5%/ year average (90L1). Zhu reported similar rates for NW China (90L1).

Very few grass-dominated natural ecosystems remain in North Africa, except for esparto grass (which is almost unpalatable). Palatable perennial grasses and legumes have been eliminated by centuries of overstocking (80L1).

Shrubs dominate grazed natural ecosystems in northern Africa in all climatic zones. The bulk of animal feed consists of 30-40% annual grasses, legumes, and forbs, 55-65% shrubs and trees, and 5% of perennial grasses and legumes (80L1).

[C2a] - Grazing Lands Degradation - Northern Africa -Tunisia -
Three times as many cattle are being grazed as are sustainable. 2/3 of Tunisia is undergoing desertification (UNEP data, 1987) (89P2).

[C3] - Grazing Lands Degradation - Eastern Africa (Ethiopia, Kenya (Nyasaland), Somalia, Sudan, Tanzania) -
[C3a] - Grazing Lands Degradation - Eastern Africa - Ethiopia -
Over-grazing is a major factor in land degradation in Ethiopia. There are 27 million cattle, sheep, and goats (the most of any nation in Africa) (87M2).

[C3b] - Grazing Lands Degradation - Eastern Africa - Kenya -

Over 50% of Kenya's grazing lands are badly eroded (83T1).

Overgrazing has seriously damaged vast areas of Kenya's semi-arid grasslands (76E1).

In eastern Kenya, a study found that rangeland with over 20% vegetative cover erodes at 600-1200 tonnes/km2/ year, while the rate for land with under 20% vegetative cover is several times larger (95W1).

[C3c] - Grazing Lands Degradation - Eastern Africa -Nyasaland (Kenya?) -
Since 1880, much of the forests had been destroyed. Intense erosion has occurred in the deforested highlands. Mountains and hills are now masses of bare rock due to fire, over-grazing, over-cropping. Kenya Land Commission concluded in 1934 that sectors of the reserves of Turkana and Suk - and probably Wakamba and Mbere - were eroded by over-grazing to the point where it may be impossible to regenerate the pastures (44H1).

[C3d] - Grazing Lands Degradation - Eastern Africa -Somalia -
Extensive additional areas of Somalia have become desert or semi-desert within the past century. Ref. 6 of (76E1) predicts that without radical changes in land-use practice, within a few decades, all of Somalia will be desert-like except for some river valleys and the moist southernmost region. Ref. 6 of (76E1) describes Somalia as "on the verge of a disaster".

[C3e] - Grazing Lands Degradation - Eastern Africa - Sudan -

Perhaps the most striking environmental phenomenon in the Sudan is the gradual shift of vegetation zones southward. (Desert creeps into steppe; steppe creeps into the savanna, and savanna creeps into the forest. (76E1).) Comments; This may be a transient effect. In more recent years the southern border of the Sahara Desert is returning northward.

A 1974 Sudanese Government study found that during the prior 17 years the desert's southern boundary has shifted southward by 90-100 km (76O1) (Ref. 6 of (78E1)).

Ref. (70K1) describes several animal-exclosure experiments (in Sudan?) that dramatically demonstrate the effects of over-grazing on land deterioration (70K1).

Acacia scrub forests were found in the Khartoum-Omdurman area in the early 1940s. In 1970 no such vegetation is to be found within 90 km. of Khartoum (70K1).

[C3f] - Grazing Lands Degradation - Eastern Africa -Tanzania -

The large and growing numbers of livestock and the cultivation of the lowland's more marginal lands have accelerated land degradation in the Pangani River basin of Tanzania (07M1) (se99.doc) (Africa.doc) (SE3)

Vast semi-arid grasslands have been seriously damaged by over-grazing (76E1).

[C4] - Grazing Lands Degradation - Sahel (Burkina Faso, Chad, Gambia, Mali, Mauritania, Niger, Senegal), -

Nearly 20% of Niger's land area is at risk of desertification ("Land resource stresses and desertification in Africa," NRCS, 2001). (Africa.doc) (SU3)

In Senegal, 500 km2/ year are being lost to deserts (Tim Large, "Advancing deserts fuel African conflict", Reuters AlertNet, 1/23/06.). (su3)

Satellite images reveal that since the mid-1980s Burkina Faso's dunes are retreating across the southern edge of the Sahara from the shores of the Atlantic to the Red Sea coast. Aerial photographs show regeneration of vegetation, more trees and grassland and a 70% increase in yields of cereals in one province. But a new analysis shows that vegetation has increased in the past 15 years, in southern Mauritania, northern Burkina Faso, NW Niger, central Chad, much of Sudan and parts of Eritrea. The main cause is increased rainfall, but farmers are using better methods of keeping soil and water on their land ("The Green Hills of Africa", New Scientist, 11/02).

West African countries devastated by advancing deserts 20 years ago, are growing greener. Vegetation is ousting sand from Mauritania to Eritrea. The greening has been happening since the mid-1980s. There is a regeneration of vegetation in northern Burkina Faso, more trees and grassland and a 70% increase in sorghum and millet in one province. In August, the World Summit in Johannesburg was told that over 45% of Africa is in the grip of desertification, with the Sahel worst affected. But a team of geographers claim that vegetation has increased. There is confusion why the Sahel is becoming green. There has been increased rainfall, but farmers have adopted better methods of farming ("Africa's Deserts Are in "Spectacular" Retreat" New Scientist, 9/18/02.)

Ref. (79S1) and its Ref. 13 cite reasons for attributing desertification of the Sahel to over-grazing. In 1972-73 the total number of grazing animals was estimated to be at least double the region's carrying capacity (76E2). Virtually all Sahel rangeland is at least moderately degraded (89P1) (89P2).

Some 650,000 km2 of land once suitable for agriculture or intensive grazing has been forfeited to the Sahara over the past 50 years along its southern fringe (Ref. 4 of (78E1)) (76E1) (77B1). Comments: Other data show the Sahara Desert growing and shrinking by about 1 million km2 from decade to decade.

Ref.(70C1) cites a 1967 study by Shinnie in support of the contention that the destruction of flora and fauna around the Sahara Desert has accelerated in recent years.

Wells being dug in 1970 merely resulted in greater production of cattle and sheep. Over-grazing consequently extended the Sahara Desert far into the marginal lands now bordering it on the south (70C1).

[C4a] - Grazing Lands Degradation - Sahel - Mali -
The Sahara Desert expanded 350 km. southward in the past 20 years (Ref. 24 of (88B1)). Comments; In more recent years the southern edge of the Sahara has been moving northward.

[C4b] - Grazing Lands Degradation - Sahel - Mauritania -
Sand dunes in Mauritania were once stationary. But now with much of the protective vegetation gone, the dunes move around, bury roads, create refugees, and cause sandstorms (88L1). There were 43 sandstorms during 1960-70. In the 1970s the number of sand storms increased by a factor of 10, and in 1983 there were 240 sandstorms (89P1) (89P2).

[C5] - Grazing Lands Degradation - Southern Africa (Angola, Botswana, Lesotho, Madagascar, Mauritius, Mozambique, South Africa, Swaziland, Zimbabwe) -

A study finds that (grazing livestock) carrying capacity is diminishing in nine southern African countries (02E1).

A study of grassland conditions in 9 countries of southern Africa reports that cattle numbers exceed carrying capacity in each country by 50-100% (Ref. 22 of (88B1)).

[C5a] - Grazing Lands Degradation - Southern Africa -South Africa -
Invasion by woody plants from over-grazing has rendered 30,000 km2 of South Africa useless for cattle. An additional 140,000 km2 of savanna is rapidly losing its ability to support livestock as scrubby brush spreads across the land (91D1).

[C5b] - Grazing Lands Degradation - Southern Africa -Botswana -

Wells drilled in grazing lands in Botswana are causing water tables to drop steadily, forcing herders to migrate or give up their stock (State of the World, 1989, p. 63).

[C6] - Grazing Lands Degradation - Central Africa (Burundi, Central African Republic, Congo, Gabon, Malawi, Rwanda, Uganda, Zambia (Namibia)) -

[C6a] - Grazing Lands Degradation - Central Africa -Rwanda -

About 3 million cattle in western Rwanda have badly eroded hillsides and have accelerated the damage to soil productivity. (The economy is almost entirely based on agriculture and livestock.) (Dejan Kovarevic, Pittsburgh Post Gazette, 4/19/94).

[C7] - Grazing Lands Degradation - Western Africa (Benin, Cameroon, Cape Verde, Cote D'Ivoire, (The) Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Nigeria, Sierra Leone). -

Nigeria, Africa's most heavily populated country, is losing 3510 km2 of rangeland and cropland to desertification each year (01B1).

Nigeria's human population was 37 million in 1950 and 148 million in 2007 (09B1).

Nigeria’s livestock population grew from roughly 6 million in 1950 to 102 million in 2007 (10B1).

Nigeria is losing 2330 km2 /year of grazing lands and croplands to deserts (Tim Large, "Advancing deserts fuel African conflict", Reuters AlertNet, 1/23/06.). (su3) Comments: This does not mean that the desert is growing of its own accord. Overgrazing, over-plowing and deforestation are creating vegetation-free zones that permit sand dunes to migrate. (Nigeria's human population was 33 million in 1960 and 132 million in 2005.)

Nigeria, Africa's most populous country, is losing 3510 km2 of rangeland and cropland to desertification each year. While Nigeria's human population grew from 33 million in 1950 to 132 million in 2005, its livestock population grew from roughly 6 million to 66 million, an 11-fold increase. The forage needs of Nigeria's 15 million cattle and 51 million sheep and goats exceed the sustainable yield of Nigeria's grasslands. The northern part of Nigeria is slowly turning to desert (06B1) (su3\)

Nigeria is losing 1355 square miles of rangeland and cropland to desertification each year. While Nigeria's human population grew from 33 million in 1950 to 134 million in 2006, its livestock population grew from 6 million to 66 million (06B2). (su3)

In Nigeria, 3,500 km2 of land are converted to desert each year, making desertification Nigeria's leading environmental problem (Lester R. Brown, "Troubling New Flows of Environmental Refugees", Earth Policy Institute, 1/28/04).

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SECTION (4-D) - Grazing Land Degradation-North America - [D1] Western US in General, [D2] Desert Lands of North America, [D3] Riparian Areas, [D4] Forested Grasslands, [D5] BLM Lands, [D6] Far West, [D7] Interior Columbia Basin, [D8]~ Indian Reservation Range Land, [D9] Great Plains, [D10] Privately-owned Rangeland, [D11] State-Owned Rangeland, [D12]~ USFS Land, [D13]~ Great Basin, [D14] Water Runoff from Grazing Lands, [D15] Exotic Species Effects, [D16]~ Juniper, [17]~ National Parks and Similar Lands,

[D1] - Grazing Lands Degradation - Western US in General -

(Historical - US) In its 1936 report on The Western Range, the Forest Service depicted the grim legacy of nearly a half-century of overgrazing. "There is perhaps," the agency observed, "no darker chapter nor greater tragedy in the history of land occupancy and use in the US than the story of the western range." In total, the USFS estimated that 75-90% of all public domain and private and state lands had been severely depleted and were in declining ecological condition (00H2).

The bulk of grazing lands in the arid regions of the US remain in relatively degraded condition with millions of hectares reported deteriorating at this moment. The best available data shows that about two-thirds of Forest Service and BLM lands are in less than good ecological condition. A total of 14% of the two agencies' lands -- almost 10 million ha -- are estimated to be declining in ecological condition, and more than 11 million ha are classified in poor ecological condition (00H2).

In an essay entitled "How the West was Eaten," author Jeffrey St. Clair tells us that most of the water in the West goes not to satiate the thirst of people but that of cows. The primary source of the pollution of that water is from the thousand tons of cow manure released into it every day. Grazing allotments cover 82% of the 320 million acres USFS and BLM controlled land in the Western US. More than 250,000 miles of ranching roads crisscross these public lands, along with an estimated 300,000 to 500,000 miles of fencing that obstructs wildlife migration routes. Wildlife Services (formerly called Animal Damage Control, see: http://tinyurl.com/yom3uo), a program of the USDA, tracks, traps, poisons, gases or shoots more than two million birds and 135,000 mammals every year, including more than 80,000 coyotes last year (see also: http://tinyurl.com/3bl2el). Native wildlife species are also at risk from lethal diseases transmitted by cattle and sheep. (see also #7 below and http://tinyurl.com/3dwwwx) (Jeffrey St. Clair, How the West was Eaten," Counterpunch, February 10/11/07 http://www.counterpunch.org/stclair02102007.html).

Approximately 464 million acres of American rangeland have undergone some degree of desertification (83D1) (94F2).

The book The Changing Mile (85H1) promoted the idea that the international borderlands of southern Arizona and northern Sonora of Mexico suffered an increase in aridity in the 19th century and argued that the observed vegetation changes in the area were caused by this aridity change - not to human land-use changes (massive overgrazing) (94F2). More recent studies (91B2) concluded "probably no single land use has had a greater effect on the vegetation of southeastern Arizona, or has led to more changes in the landscape than livestock grazing range management programs. Undoubtedly, grazing since the 1870s has led to soil erosion, destruction of those plants most palatable to livestock, changes in regional fire ecology, the spread of both native and alien plants, and changes in the age structure of evergreen woodlands and riparian forests". Bahre (91B2) also concluded "the present historic evidence...casts serious doubt on the hypothesis that a shift toward greater aridity is the primary factor for regional vegetation changes" (94F2).

Grazing is credited with transforming southern New Mexico from grassland to creosote bush desert (38W1) (69Y1) (94F2).

Grazing in the western US occurs in creosote bush deserts, blackbrush deserts, slickrock mesas, sagebrush flats, pinyon-juniper woodlands, chaparral, ponderosa pine forests, and alpine meadows above timberline (94F2).

70% of the 11 western states of the US (MT, WY, CO, NM, and westward) is grazed, including wilderness areas, wildlife refuges, national forests and some national parks (94F2).

Cheney, Elmore, and Platts (90C1) state "In 1980, the US Department of Agriculture estimated that the vegetation on more than half of all western rangelands was deteriorated to less than 40% of potential production, and to less than 60% of potential on more than 85% of the rangeland." (From a letter from Joy Belsky 1/7/00 to the Atlantic Monthly regarding an article by P. Knize on grazing issues in the western US).

The US Soil Conservation Service says more than 410 million acres (1.66 million km2) of public and private grazing lands are in unsatisfactory condition - 21% of the US outside of Alaska. Nearly all these degraded lands are in the West (99W1).

Although there may have been some improvements in grazing management, the increase of cattle in the West [doubling over the past 5 decades] suggest that grazing impacts will continue into the foreseeable future (95T1 in (99B1)).

A 1990 BLM report stated that "the public range was in the best condition yet this century, and improving." A 1991 GAO report countered that "We could not confirm BLM's conclusion that the public rangeland is in better condition than ever before in this century because the historic studies BLM relied upon were prepared using different methodologies in some cases, and in other instances did not contain supporting documentation."

Livestock grazing is the fourth major cause of species endangerment in the US and the second major cause of endangerment of plant species (94F1 in Ref. (99B1)).

The US SCS estimates that less than 50% of the original rangeland topsoil of the western US remains (p. 78 of (91J1)).

Exclosure studies in forested ecosystems in the Interior US West consistently find that livestock substantially reduce vegetative cover, especially that of perennial bunchgrasses. In a Bitterroot Mountain study, grazing reduced the productivity, frequency and cover of several perennial bunchgrasses by 50-100%, and increases in annual grasses and perennial weeds was not enough to make up the difference (97B2).

In 1980 the US Dept. of Agriculture estimated that the vegetation on more than 50% of all western rangelands was deteriorated to less than 40% of potential productivity, and to less than 60% of potential productivity on more than 85% of these rangelands (90C1).

The US SCS reports (1981) an average US topsoil erosion rate of 4.2 tons/ acre/ year on grazed forest, and 3.1 tons/ year on grazed rangelands. Pimental suggests that range soil is eroding 20 times faster than it is being replaced (p. 79 of Ref. (91J1)). US pastures lose 600 tonnes/ km2/ year of topsoil (Ref. 13 of Ref. (95P1)).

Ref. (97B3) lists the major environmental problems in grazed ecosystems in the US as:

US Topsoil erosion rates (1977) (80U1)
(Erosion rates in tons/ acre/ year (and tonnes/ km2/ year))
Pasture land, including native pasture | 2.6 (584)
Rangeland~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ | 3.1 (696)
Grazed forest land ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ | 4.2 (943)
(Native pasture is land with sub-climax plant communities managed for grazing on potential forest land.) Comments: These topsoil erosion rates are probably net rates (in excess of natural topsoil-creation rates on grass lands (about 100 tonnes/ km2/ year)). For gaining perspective, topsoil inventories on grasslands are typically on the order of 380,000 tonnes/ km2. Typical topsoil erosion rates on croplands are on the order of 1800 tonnes/ km2/ year but can be a factor of 10-20 higher in extreme cases. Some African grazing lands have topsoil erosion rates of about 10,000 tonnes/ km2/ year.

A map of the western US showing the extent of soil erosion (slight, moderate, severe) in 17 western states is in Ref. (82S1).

Half of US rangeland is severely degraded (91D1).

Violent flooding became common with the introduction of livestock in the 1800s. The commencement of greatly increased destructive flooding and the peak in livestock numbers occurred simultaneously in many western regions: (1875-95 in AZ; 1860-70 in CA, 1870s and 1880s in WY; 1880s to early 1900s in New Mexico) (p. 104 of Ref. (91J1)).

130 years ago, it was unusual to encounter an arroyo (eroded drainage with a flat floor and vertical banks) or cutback or even a scoured wash in most of the western US. In the Southwest the only stream for which significant pre-1850 arroyo trenching is well documented is the Rio Puerco NM where currently there exists vastly larger arroyos than in pre-1850 (p. 105 of (91J1)). Comments: Typical topsoil erosion rates under conditions of gully (arroyo) erosion are about 40,000 tonnes/ km2/ year.

A USDA (USFS?) report in 1936 said "A range once capable of supporting 22.5 million AU can now carry only 10.8 million AU (86J1) (94O1).

August L. Hormay, perhaps the leading range expert in the US, estimates that livestock grazing capacity has been reduced by 50% or more on western US grazing lands (70H1).

The Great Plains once supported 200-250 cattle/ mi2 (77-96/ km2). The dust bowl disaster prompted federal grazing regulations leading to today's cattle densities of 50-100 head/ mi2 on the same ranges. Despite these regulations, as much as 28% of the 163 million acres of federal rangelands have been made almost useless by over-grazing and are in poor condition according to the CEQ (77B1).

A GAO report (CED-77-88, $1 from USGAO Distribution Section, P.O. Box 1020, Washington DC 20013) claims that the quality of US public rangeland continues to deteriorate, and that the problem is "principally poorly-managed livestock grazing" (77U1).

In 1935, over 58% of the US public range was in poor condition. By 1972, this had decreased to 32% (83B2).

It has been accepted doctrine that, from the 1880s onward (and before that in the southern plains), we have had, recurrently, the grazing of one or another portion of the range at a pressure causing serious deterioration of the cover (p. 744 of (56C1)).

The US Council on Environmental Quality (CEQ) reported 1/3 of US range land (exclusive of Alaska) in fair condition, and 1/3 in poor condition (Ref. 21 of (84B1)).

About 15-25% of US range lands are undergoing serious degradation from improperly controlled livestock grazing (93H1). 35-40% of US range lands are either stable or in very slow decline (93H1).

Over-grazing of US range lands accounts for the fact that about 70% of western US grazing lands are producing under 50% of their forage potential (Ref. 1 of (78D1)).

In the US, there are 225 million acres (the size of the 13 original states) in a state of severe desertification, and another equally large area that is endangered of severe desertification (87H1).

Condition of US Rangeland by State as of 1976 (Areas are in units of 1000 acres) (Table 5.1 of Ref. (80H1))
Region - - - | Total | Good | ~Fair | Poor |Very Poor
Northeast~ ~ | ~ 146 | ~ ~ 8| ~ ~14 | ~ ~14| ~ 110
North Central| ~1652 | ~ 191| ~ 451 | ~ 698| ~ 311
Southeast~ ~ | ~2237 | ~ 222| ~ 293 | ~ 464| ~1258
South Central| ~ 991 | ~ ~31| ~ 622 | ~ 309| ~ ~28
Rocky Mtn. ~ |382180 | 54194|126739 |146235| 55012
Great Plains |177150 | 25972| 54850 | 69125| 27202
Pacific N.W. | 32699 | ~6738| 11444 | 10559| ~4318
Pacific S.W. | 53290 | ~9365| ~9090 | 17184| 17651
Total (48 St)|650345 | 96361|203503 |244588|105891
Alaska ~ ~ ~ |231471 |183272| 43876 | ~4323| ~ ~ 0
Hawaii ~ ~ ~ | ~ 968 | ~ 343| ~ 166 | ~ 198| ~ 261
Total (50 St)|882784 |279975|247545 |249109|106152
"Good" means capable of producing at 61-100% of the site's ecological potential; "Fair" 41-60%; "Poor" 21-40%, "very Poor" 0-20% (80H1).

Condition of US Range Land by Ecosystem as of 1976
(Areas are in units of 1000 acres) (Table 5.2 of Ref. (80H1))
Ecosystem - - - - -| Total| Good | Fair | Poor | Very Poor
Contiguous States
Grasslands
Mountain Grassland | 26871| ~4705| ~9725| ~8392| ~4049
Mountain Meadows ~ | ~3284| ~1063| ~1275| ~ 692| ~ 253
Plains Grasslands~ |175239| 25809| 59874| 69377| 20178
Prairie~ ~ ~ ~ ~ ~ | 41186| ~5740| 14098| 15695| ~5654
Desert Grasslands~ | 24744| ~2086| ~6109| 12483| ~4066
Wet Grasslands ~ ~ | ~4411| ~ 748| ~1219| ~ 911| ~1533
Annual Grasslands~ | 10153| ~1336| ~ 511| ~3731| ~4576
Alpine ~ ~ ~ ~ ~ ~ | ~6775| ~2897| ~1835| ~1948| ~ ~95
Total Grasslands ~ |292663| 44384| 94646|113229| 40403
Shrub-Lands
Sagebrush~ ~ ~ ~ ~ |129872| 16012| 46794| 45470| 21495
Desert Shrub ~ ~ ~ | 81171| 14130| 29581| 25547| 11913
Shinnery ~ ~ ~ ~ ~ | ~4726| ~ 780| ~1310| ~1915| ~ 723
Texas Savanna~ ~ ~ | 28429| ~4666| ~6689| 13037| ~4037
S.W. shrub-steppe~ | 43213| ~4535| ~6398| 17923| 14358
Chapparal-Mtn.Shrub| 15477| ~1829| ~3711| ~5870| ~4063
Pinyon-juniper ~ ~ | 47305| ~4285| 13509| 21012| ~8498
Desert ~ ~ ~ ~ ~ ~ | ~7490| ~5739| ~ 865| ~ 486| ~ 400
Total Shrub Lands~ |357683| 51976|108857|131360| 65488
TOTAL (48 States)~ |650346| 96361|203503|244588|105891
Alaska#~ ~ ~ ~ ~ ~ |321471|183272| 43876| ~4323| ~ ~ 0
Hawaii@~ ~ ~ ~ ~ ~ | ~968 | ~ 343| ~ 166| ~ 198| ~ 261
Total (50 states)~ |882784|279975|247545|249109|106152

# (broken down in (80H1) into muskeg-bog, shrub thickets, moist tundra, wet tundra, alpine tundra, Aleutian moist tundra, Aleutian alpine
@ (broken down in (80H1) into forest-shrub-grass mosaic, koa-mamani-parkland, and grass-shrub-barren mosaic)

Range Conditions of the Public Lands of the 11 Western States (89W2) (areas in 1000 acres)
State| Excellent | ~Good ~ ~ ~ | ~Fair ~ ~ ~ | ~Poor
AZ ~ | 420.4(3.5%| 2797.0(23.0%| 5897.6(48.5%| 3042.6(25.%
CA ~ | ~16.0(0.2 | 3158.5(38.7 | 4000.3(49.0 | ~985.8(12.1
CO ~ | ~45.9(0.8 | 1030.7(17.0 | 2804.1(46.2 | 2191.4(36.1
ID ~ | 112.1(1.1 | 2145.7(21.7 | 3232.7(32.7 | 4399.9(44.5
MT ~ | 524.9(7.7 | 4439.5(65.0 | 1807.6(26.4 | ~ 62.8( 0.9
NV ~ | 427.4(1.1 | 7991.3(20.1 |14535.7(36.7 |16694.2(42.1
NM ~ | 107.3(0.8 | 3734.2(27.1 | 7035.2(51.1 | 2893.3(21.0
OR/WA| ~89.5(0.7 | 3305.3(27.4 | 6484.4(53.8 | 2164.4(18.0
UT ~ | 934.5(5.0 | 6219.6(33.1 | 8747.0(46.5 | 2907.3(15.5
WY ~ | 708.8(6.4 | 5533.3(50.2 | 3615.0(32.8 | 1170.5(10.6
Total|3390. (2.4 |40360. (29.2 |58160. (42.0 |36510. (26.4
Total Area = 138,413,895 acres (560,380 km2)

About 70% of western US grazing lands are producing at less than 50% of their potential - a result of past over-grazing (78D1).

Some 54% of US pasture land is over-grazed and subject to high rates of topsoil erosion (Refs. 25 and 26 of Ref. (95P1)).

Half of US range land is considered severely degraded, with its livestock-carrying capacity reduced by at least 50% (Ref. 26 of Ref. (95D1)). (la)

Of 410,000 mi2 of US public rangeland, 30.5% is in poor condition, 50% is in fair condition (72H1). 50% of federal rangelands are in a state of severe-to-critical erosion; 32% are eroding moderately, and 18% have slight- or no erosion (72H1).

According to USDA analysts, close to 1/3 of all non-federal rangeland was over-grazed in 1976 (Ref. 66 of Ref. (82W1)). Of the 27% of western grazing lands that are in private ownership, 68% is in fair or poor condition (1975) (86J1).

A 1990 BLM survey found 33% of US grazing lands to be in good or excellent condition (Ref. 6 of Chapter 6 of Ref. (94B3)).

The vast bulk of US range that agencies term "satisfactory" is producing biomass at less than 50% (some less than 20%) of its pre-livestock rate. By industry standards, an allotment rated in 100% "excellent" condition may still be only 50% as productive as it was originally (p. 442 of Ref. (91J1)).

Some 2.8 million km2 (36.8%) of North America's arid land area have undergone "severe" desertification; 27,200 km2 have undergone "very severe" desertification (Ref. 9 of Ref. (81S1)) (81S3).

Prior to 1900, most bluestem pastures could be stocked at 2 acres for one mature cow or steer for a 6-month grazing period. Now the average grazing cap is about 7 acres/ animal (p. 45 of (91J1)).

Shrub land range is in worse shape than grassland range. 55% is producing at less than 40% of its biotic potential, and 85% is producing at less than 60% of potential (p. 57 of (91J1)).

Vegetation on more than half of all western range lands has deteriorated to less than 40% of potential productivity, and 85% has deteriorated to less than 60% of potential productivity (from a 1990 report prepared for USEPA by Chaney) (p. 66 of Ref. (91J1)).

[D2] - Grazing Lands Degradation - Desert Lands of North America -

While 20% of the western US could be termed true, natural desert, perhaps another 20% has been so thoroughly and incessantly grazed by livestock that it has taken on the appearance of a desert. The Sonora and Chihuahuan Deserts of the US southwest have become perceptibly more barren during the past century (p. 61 of (91J1)) (81S1).

Dregne estimates 225 million acres (910,000 km2) of land in the US have experienced "severe" or "very severe" desertification (10% of the US land mass). The area threatened by "severe" desertification is almost twice as large (Ref. 10 of (81S1)).

A map of desertification in the western US is shown in Refs. (85R1) and (81S1), showing four grades of severity.

A map showing the deserts of the US and northern Mexico is given in Ref. (81S1) (Mojave, Sonoran, Great Basin and Chihuahuan).

A 1978 study of the western Mojave Desert found a 60-90% reduction in the cover of annuals, and a 16-29% reduction in perennials on areas used for sheep grazing (p. 62 of Ref. (91J1)).

The grassland- and grassland/ shrubland of much of the Great Basin once averaged 80% bunchgrass and forbs and 20% shrubs and brush. Now it is 20% grass (mostly exotics) and forbs and 80% woody vegetation (not counting bare dirt, sand and gravel) (p. 65 of Ref. (91J1)).

Large-scale destruction of desert soils by ORVs is documented in (77W1), (76W1), (76N1), and (76S2).

100-150-years of livestock grazing in the intermountain West has:

Research on the environmental effects of BLM-authorized sheep grazing on four sites in the western Mojave Desert in 1978 found that heavy grazing caused an over 60% reduction in annual vegetation and a 16-29% decrease in perennial cover. The sheep also caused significant soil compaction that could hinder the return of annuals. The changes indicate that the quality of the Mojave Desert is deteriorating under sheep-grazing pressures (Ref. 84 of Ref. (81S1)).

[D3] - Grazing Lands Degradation - Riparian Areas of North America -

BLM figures show that more than half of the area along the agency's 8,480 km of perennial streams in Colorado are in poor condition, and more than 80% of the area along its 18,987 km of streams in Idaho are degraded (00H2).

Tougher rules from the Clinton administration resulted in gradual improvements in streams on western US public grazing lands. In 1995 27% of BLM streams were classified as in "proper functioning condition" by BLM scientists. By 1998, the total had risen to 36% USDA (Paul Rogers and Jennifer LaFleur, San Jose Mercury News, 12/5/99).

Grazing remains "the most insidious threat to the riparian habitat type today (77C1).

The degradation of Western riparian habitats began with the severe overgrazing in the late 19th century (90C1).

The Environmental Protection Agency (EPA) concluded that riparian conditions throughout the US West are now the worst in American history (90C1).

Prevention of seedling establishment due to grazing and trampling by livestock has transformed a variety of Southwestern US riparian habitats into even-aged, non-reproducing vegetative communities (77C1) (89S1).

Cattle grazing of small seedlings prevented cottonwood regeneration in a southern Arizona riparian zone (77G1).

Grazing can eliminate a willow stand from a riparian area within 30 years (92K1).

Could riparian habitats be protected or restored by fencing? Consider a rough estimate of the financial cost of riparian fencing just on Western BLM lands. Fencing costs per mile have been estimated at $8,000-12,000 (96O2). There are reportedly 36,631 linear miles of riparian zones on BLM lands in the 10 Western states (Washington not reported). ((98B2) Table2-2) Assuming that the number of riparian miles grazed by livestock is directly proportional to the percentage of Western BLM lands that are grazed by livestock, i.e. 94% (94F2 p.630), gives 34,433 riparian miles subject to livestock impacts. Fencing these areas would cost $275-$413 million. BLM lands provide 13,303,000 AUMs of livestock forage annually ((94U2): Fig. 2-5).

Livestock grazing has been found to negatively affect water quality and seasonal quantity, stream channel morphology, hydrology, riparian zone soils, in-stream and stream-bank vegetation, and aquatic and riparian wildlife. No positive environmental impacts of livestock on riparian ecosystems have been found (99B1).

"Extensive field observations in the late 1980's suggest riparian areas throughout much of the West were in the worst condition in history." ((90C1): p.5).

Cows have damaged approximately 80% of the streams and riparian ecosystems in the arid regions of the western US (94U2).

Cheney, Elmore, and Platts wrote in "Livestock Grazing on Western Riparian Areas" (90C1), that "extensive field observations in the late 1980s suggest riparian areas throughout much of the West were in the worst condition in history." This is one of the most frequently cited papers in the range science literature and was written for the Environmental Protection Agency by three of the foremost fisheries and riparian specialists in the country. Author Wayne Elmore is a top riparian specialist for the Bureau of Land Management and William Platts is a nationally respected fisheries biologist with the US Forest Service (From a letter from Joy Belsky 1/7/00 to the Atlantic Monthly regarding an article by P. Knize on grazing issues in the western US).

A 1999 study published in Journal of Soil and Water Conservation found that livestock grazing has damaged 80% of stream and riparian ecosystems in the western US. While these areas compose less than 1% of the overall landscape, 70-80% of all of the wildlife in the West depends on this habitat (01E1).

About 80% of all streams and riparian ecosystems in the arid West are severely degraded by livestock grazing. In its Global 2000 report, the Council on Environmental Quality noted, "improvident grazing ... has been the most potent desertification force, in terms of total acreage (351,562 square miles), within the US" (02R1).

US (western??) riparian areas are in the worst condition in history. Livestock are the major source of riparian degradation on western public lands. (1989 GAO report) (1990 EPA report) (99W1).

Extensive field observations in the late 1980s suggest that riparian areas throughout the West were in the worst condition in history (from a 1990 Chaney report to USEPA) (p. 95 of Ref. (91J1)) (Ref. 49 of Ref. (91D1)) (90C1).

Southwest Center for Biological Diversity 6/29/99 reported in Journal of Soil and Water Conservation a summary of over 140 peer-reviewed scientific papers on the effects of grazing on western rivers and riparian areas. More than 100 papers found livestock grazing reduced water quality, compacted soils, increased sedimentation and harmed fish and wildlife. See http://www.onda.org/rippaper.html.

A joint BLM/ USFS report concluded in 1994 that "riparian areas have continued to decline [since 1934] (p. 25), and estimates that 20% of riparian areas managed by the BLM are "non-functioning", and 46% are "functioning at risk". Altogether, less than 20% of potential riparian habitats in the western US still exist. (See http://www.rangenet.org/projects/warcomments.html)

Forage utilization by livestock was 7.5 times higher in riparian meadows than in adjacent uplands (82B2) (97B2). A riparian zone in a forested watershed in Oregon comprised 1.9% of the allotment, but produced 21% of available forage and 81% of forage consumed (82R2) (97B2).

One US study (90S2) (97B2) found that grazed areas of a riparian meadow had 50% lower litter cover and 400% more bare ground than ungrazed areas. Soil surface litter is critical for slowing overland flow, promoting water infiltration, serving as a source of soil nutrients and organic matter, and protecting soil from freezing and erosive force of rain drops (97B2).

The extensive deterioration of western US riparian areas began with severe over-grazing in the late 19th and early 20th centuries. Native perennial grasses were virtually eliminated from vast areas and replaced by sagebrush, rabbitbrush, mesquite and juniper, and by exotic plants or shallow-rooted native vegetation less suited for holding soils in place (90C1).

Only a small portion of the tens of thousands of miles of riparian habitats in the Western US are in good condition. Poorly managed livestock grazing is the major cause of degraded riparian habitats on federal rangeland (p. 96 of Ref. (91J1)).

The US BLM estimates that 34% of its riparian areas are in proper functioning condition; 46% are functioning at risk, and 20% are non-functioning. ("Functioning at risk" means vegetation and soils are susceptible to losing their ability to sustain natural functioning biotic communities. "Non-functioning" means vegetation and ground cover are not maintaining soil conditions that can sustain natural biotic communities.) (94B2).

In uplands, grazing has fewer effects on shrubs than on grasses, but in riparian areas, grazing dramatically reduces the number and total biomass of shrubs and trees (which are crucial for shading streams, stabilizing stream banks and providing wildlife habitat (97B2).

Riparian areas (in the western US) have continued to decline since 1934 (94U2 in (99B1)).

Extensive field observations in the late 1980s suggest that riparian areas throughout much of the western US were in their worst condition in history ((90C1) in Ref. (99B1)).

Livestock grazing remains a key factor in the continued degradation of riparian habitats (89S1 in (99B1)).

Riparian habitats in the West were viewed until the late 1960s as "sacrifice" areas dedicated to providing food and water for domestic livestock ((55S1) in Ref. (99B1)).

Riparian- and stream ecosystems represent 0.5-1.0% of the surface area of arid lands in the 11 western US ((90C1) in Ref. (99B1)). (la)

Grazing by livestock has damaged 80% of the streams and riparian ecosystems in the arid region of the western US ((94U2) in Ref. (99B1)).

Ref. (99B1) cites 12 references supporting her conclusion that even those who strongly believe grazing to be compatible with healthy riparian ecosystems point out that 2-15 years of total livestock exclusion are required to initiate the recovery process, and that streams that are permanently protected from grazing have the highest probability of successful recovery.

Riparian specialist Robert Ohmart (University of Arizona) questions whether weakened and degraded riparian communities throughout the arid West can "hang onto their thread of existence for another 30-50 years" while waiting for grazed systems to recover ((96O1) in Ref. (99B1)).

Ten years of livestock exclusion are necessary to reverse a negative trend and allow stream conditions to begin to improve (96S2 in Ref. (99B1)).

A diagram showing the steps in the sequential degradation of a stream channel due to removal of riparian vegetation by livestock grazing is shown in Ref. (99B1) and (94U2).

Less that 20% of potential riparian habitat in the western US still exists (94U2 in Ref. (99B1)).

20% of the riparian areas managed by the BLM are "non-functioning" and 46% are "functioning at risk" (94U2 in Ref. (99B1)).

[D3a] - Grazing Lands Degradation - Riparian Areas -Arizona -

Four Arizona major drainages (Santa Cruz, San Pedro, San Simeon and Little Colorado) were once described as lush and green. These riparian areas are now dry along most of their lengths, except for violent floods draining from over-grazed rangeland - no trees, very little grass, no beaver, trout or accumulated vegetation (p. 98-99 of (91J1)). The desert's flood-plain vegetation has changed almost beyond recognition in such areas as the Santa Cruz River Valley of Arizona (81S1). About 312 mi2 of valley alluvium in the Santa Cruz and San Pedro Basins is undergoing "severe" erosion (over 9000 tonnes/ km2/ year) (Ref. 234 of (81S1)). The USDA estimates that 190 miles of stream banks in the basin are unstable due to over-grazing (81S1).

The Arizona Game and Fish Dept. reports that 97% of the state's original riparian habitats have been lost, with ranching the major factor (p. 99 of Ref. (91J1)). Cottonwood regeneration along Arizona's Gila River Box Canyon was almost non-existent due to over-grazing. The BLM's wildlife budget paid for fencing and replanting (89W1).

According to the Arizona State Parks Department, 90% of the original riparian ecosystems in Arizona and New Mexico are gone.

Before about 1880, the Gila River channel from Santa Cruz Junction to Yuma was narrow with firm banks bordered by cottonwoods and willows, but by the early 1890s, it occupied a sandy waste 0.25-0.5 mile wide (J.J. Wagoner, History of the Cattle Industry in Southern Arizona, 90C1).

Over 90% of Arizona's original riparian habitat is gone (Johnson, 1989).

[D3b] - Grazing Lands Degradation - Riparian Areas -California -

California has lost 89% of its riparian woodlands since 1848, largely to ranching, farming, dams and mining (p. 99 of Ref. (91J1)).

Less than 5% of the riparian habitat in California's Central Valley remains: 85% of that is in disturbed or degraded condition (87F1).

[D3c] - Grazing Lands Degradation - Riparian Areas -Colorado -

90% of 5300 miles of riparian habitats surveyed in Colorado were rated in poor or fair condition due to livestock (p. 99 of Ref. (91J1)). A 1988 GAO report stated that 90% of the 5300 miles of streamside habitat managed by the BLM in Colorado are in unsatisfactory condition.

[D3d] - Grazing Lands Degradation - Riparian Areas - Idaho -
80% of the 12,000 miles of streams and associated riparian zones on BLM lands in Idaho are being damaged by poor management (p. 99 of (91J1)). 80% of the Idaho BLM's riparian lands are degraded (George Wuethner, Sierra, Sept.-Oct. 1990).

[D3e] - Grazing Lands Degradation - Riparian Areas -Nevada -
A BLM report on riparian habitats states that stream riparian habitats where livestock grazing is occurring have been grazed out of existence, or are in a severely deteriorated condition. Within Nevada, 883 miles of streams were identified as having deteriorated- or declining habitat (79F1).

[D3f] - Grazing Lands Degradation - Riparian Areas - New Mexico -

90% of the original riparian ecosystems in New Mexico are gone (p. 99 of Ref. (91J1)).

A 1998 report from the New Mexico Environment Department to the US EPA concluded that nearly 85% of all stream miles in New Mexico violate state water quality standards, and that 96% of all water pollution in the state is from non-point sources. The report identified livestock grazing and agriculture as the leading causes of non-point source pollution (98U1).

[D3g] - Grazing Lands Degradation - Riparian Areas -Wyoming -

The Game and Fish Department estimates a loss of 45% of riparian area, largely from ranching (p. 99 of Ref. (91J1)). A 1988 study of 262 miles of Wyoming streams found only 2% functioning as in 1850. 83% were lost or destroyed by over-grazing and accelerated erosion (p. 92 of Ref. (91J1)).

[D4] - Grazing Lands Degradation - Forested Grasslands -
Trampling and grazing of dry and moist forests on public lands in the Interior Columbia Basin (approximately 20 million acres) changed the composition and dynamics of the forests by reducing the abundance of the grasses and sedges that historically had:
(1) served as fuel for the low-intensity, surface fires,
(2) out-competed tree seedlings for water and light.
Consequently, these grasses and sedges were critically important for thinning tree seedlings and keeping forests open and the trees well spaced. By reducing the cover and biomass of the herbaceous cover, livestock contributed to reductions in frequency of low-intensity fires and interspecific competition, and therefore, to higher densities of tree seedlings and saplings. Eventually, these seedlings and saplings developed into forest stands that were overstocked with fire-intolerant species and had greater numbers of diseased and water-stressed trees, higher fuel loads, and a potential for more and hotter fires ((51R1), (83M1), (84Z1), (90S3), (96B1) in (97B3)).

[D5] - Grazing Lands Degradation - BLM Lands -

Of the BLM lands in 16 western US states, 94% is grazed (94F2).

In 16 western US states, 165 million acres of BLM land and 103 million acres of US Forest Service lands are grazed by 7 million head of livestock, primarily cattle (94F2).

Range condition is improving on 15% of BLM land, and continues to decline on 14% of BLM land (Statistics compiled by Society for Range Management) (99W1).

Of western BLM lands for which data were available (80%), over 71% (340,000 km2) is in "unsatisfactory" condition (producing at under 40% of its present (as opposed to pre-livestock) biological potential (91J1).

In a 1975 BLM study of 170 million acres (690,000 km2) of its rangeland, 50% were in fair condition, 28% were in poor condition, 5% were in bad condition, and 17% were in excellent- or good condition. Conditions on 65% were static, 19% were improving, 16% were declining. Projections (Ref. 42 of Ref. (81S1) indicated a decline in productivity by as much as 25% over the next 25 years. More recent analyses by the GAO and BLM (Ref. 43 of (81S1)) suggest that these figures under-state the poor and deteriorating state of public range land (81S1) (81S3) (87L1). "Fair" condition means that the valuable forage species have been depleted and have been replaced by less-palatable plants or bare ground. "Poor" condition means stripped of much of its topsoil and vegetation-cover, and producing at only a fraction of its potential. "Bad" condition means most topsoil is gone (78B1).

A BLM internal memo said that grazing-induced erosion is the nation's "biggest source of resource deterioration and environmental degradation" (75W1).

The BLM is quoted as writing: "There is very little of the western range where, because of the destruction of the plant-cover by improper management, accelerated erosion has not destroyed a portion of the soil mantle and thus reduced the total productivity of the site" (75W1).

The BLM said in 1979 that 135 of its 170 million acres of rangeland were in fair condition or worse (85R1).

In 1985 the BLM inventoried 68% (118 million acres) of its rangeland and found 71% in unsatisfactory condition. On the BLM's Challis (ID) Planning Unit, 94% of the 352,000 acres were in poor- to fair condition; 52% of the area was experiencing moderate- to severe soil erosion (89W1).

Condition of BLM lands (1987): 3% excellent, 30% good, 39% fair, 19% poor (90B1).

A 1988 GAO report found that nearly 60% of the grazing allotments (for which BLM range managers had current status information) were in less-than-satisfactory condition. Only 25% of these allotments were improving. On 75% of the allotments threatened with over-grazing, the BLM had not scheduled any action to reduce authorized grazing levels (89D1).

A 6/30/89 condition report said 94 million acres (68+%) of its lands are in unsatisfactory condition. Available data do not reveal any significant improvement since the 1985 report (89W2). Since May, 1978, the BLM has reported that range conditions have improved on 1,392,000 acres (under 1%) of its acreage (89W2).

BLM estimates that 57% of its uplands (non-riparian) are in proper functioning condition, 30% are functioning at risk, and 13% are non-functioning (94B2).

[D6] - Grazing Lands Degradation - Far West - [D6a] Arizona, [D6b] California, [D6c] New Mexico, [D6d] Nevada, [D6e]~ Oregon,

[D6a] - Grazing Lands Degradation - Far West - Arizona -

In 1870 there were 5000 cows in all of the Arizona territory. By 1890 there were 1,095,000 cows on Arizona ranchland. Photos in 1892-3 showed thousands of square miles of grasslands denuded of cover (81S3).

12% of the rangelands of (Arizona's) Santa Cruz and San Pedro watersheds - 970,000 acres - are undergoing critical erosion (Ref. 41 of (81S3)) (81S1).

The USDA estimated that the Indian lands in (Arizona's) Santa Cruz Basin had the "potential" for much more grazing. This statement was made when the USDA was air-dropping hay bales into Papago Indian Reservation to feed starving cattle (81S1).

Southeast Arizona was a grassland before 1880. Today shrubby plants dominate. From 1880-1900 dramatic changes in composition of vegetation occurred along major waterways. Flooding and resulting channelization, plowing of floodplains, and livestock grazing essentially eliminated the natural processes of shallow groundwater recharge. Changes in vegetation in upland range during 1930-80 were just as destructive (83C1).

Coronado National Memorial (Arizona) is a 4,750-acre national park on the south end of the Huachuca Mountains near Sierra Vista and the Mexico border. 39% of this park, divided into 2 allotments, is set aside for cattle grazing. On one allotment, Joe's Spring, degraded uplands, cow-blasted riparian corridors, rocks and bare ground characterize this ecologically sterilized pasture (Tim Lengerich (timlengerich@hotmail.com) Friends of Coronado National Forest, 4/12/00).

[D6b] -Grazing Lands Degradation - Far West - California -

Most of California's once-lush grass- and flower-carpeted hills and valleys are covered with sparse, over-grazed exotic grasses, "weeds" and bare dirt (p. 65 of Ref. (91J1)).

2.2 million acres in the foothills and mountains of (California's) San Joaquin Basin are under moderate-to-severe water erosion (sheet- and gully type) as a result of over-grazing (Ref. 149 of Ref. (81S1)). W. O. Beatty, SCS, claims that grazing lands along the west rim of the San Joaquin Basin are still deteriorating (81S1).

On 338,000 acres (1370 km2) of San Joaquin Basin range lands, an inter-agency study found that forage vegetation was so badly over-grazed that it could not revegetate - it had undergone desertification (81S1) (Ref. 98 of Ref. (81S2)).

Of the 4 million acres (16,000 km2) of private rangeland in (California's) San Joaquin Valley, 80% had problems with over-grazing (erosion, invasion of weeds and brush). Of the public (USFS) rangelands in the San Joaquin Valley, 102,000 acres (17%) had over-grazing problems. The 400,000 acres (1,600 km2) of BLM lands there are thought to be in the same condition as private land (Ref. 144 of Ref. (81S1)).

[D6c] - Grazing Lands Degradation - Far West - New Mexico -

The 3.9 million-acre Rio Puerco River Basin (40 miles NW of Albuquerque) is one of the most eroded and over-grazed river basins in the arid west. It began around 1900, and has yet to recover. Water tables began dropping in the late 1880s, arroyo-cutting began, and sediment flowed (1.1-1.5 billion tons into the Rio Grande during 1885-1962 (81S3)). During 1931-38 the bed of the Rio Grande River rose 5 ft. down-stream of the mouth of the Rio Puerco (Ref. 50 of (81S1)). The BLM projects that the vegetation in (New Mexico's) Rio Puerco Valley that is in poor condition will increase from today's 85,651 acres (347 km2) to 170,700 acres (691 km2) by 2000 under current grazing practices. Land suffering "moderate" to "severe" soil erosion will increase to 360,550 acres (1460 km2) (73% of the public land in the valley) (Ref. 34 of (81S3)). By 1950, all settlements in the Rio Puerco valley had become ghost towns. In the late 1930s the average arroyo was 35' deep and 120' wide (81S3).

In the Gila and Aldo Leopold Wilderness areas in New Mexico, the USFS has permitted continued severe overgrazing, dozens of new permanent grazing improvements, such as stock tanks, and inappropriate use of mechanized equipment. In one incident, the allottee used a bulldozer to channelize a wilderness stream to maintain water flow to stock tanks. The permit holder is an East Texas bank that acquired the grazing permit when it foreclosed on the allottee (94D1).

Forest Guardians has taken the USFS to court to stop overgrazing on 300,000 acres of Lincoln NF, in New Mexico. Monitoring shows that "cattle are consuming up to 92% of the forage" on some grazing allotments, in violation of "allowable use standard" - 35% (ENS 4/10/00).

[D6d] - Grazing Lands Degradation - Far West - Nevada -

The carrying capacity of Nevada's BLM range is 1,836,912 AUMs for sheep and cattle according to range surveys. Class I livestock qualifications total 2,938,621 AUMs statewide - an amount in excess of grazing capacity by about 60% (74H1).

[D6e] - Grazing Lands Degradation - Far West - Oregon -

Camp Creek (central Oregon) valley floor, in 1875, was non-gullied meadow with several marshes. After 28 years of heavy grazing, the USGS described the Creek valley as arroyos 15-25' deep and 25-100' wide (p. 91 of Ref. (91J1)).

[D7] - Grazing Lands Degradation - Interior Columbia Basin -

Anderson (91A2) reviewed the literature on grazing on bluebunch wheatgrass in the Northwest and concluded that grazing damages bluebunch wheatgrass, the most important native bunchgrass in the Interior Columbia Basin, during all seasons of the year, including during the dormant season. He found that grazing was especially damaging during the spring (97B3).

Development of the Northwest livestock industry in the Interior Columbia Basin in the late 1800s introduced intensive herbivory to herbaceous plant species that had not evolved with heavy grazing (97B3). It also introduced extensive soil disturbance from trampling, heavy use of riparian habitats, and intense competition for resources to plant communities and wildlife that were dependent on clean cold water, native bunchgrass communities, periodic, low-intensity fires, and on healthy soil crusts of lichens, algae, and mosses (microbiotic crust) (97B3).

About 70% of rangelands in the Interior Columbia Basin are rated as having "low ecological integrity", 70% of Basin streams and riparian areas are classified as being "non-functional" or "functional at risk", and 5% are rated as having "high ecological integrity" (97B3).

In Bear Creek watershed (Eastern Oregon), over-grazing has caused extensive sheet- and gully erosion, destruction of all but a few perennial grasses, and the invasion of sagebrush and cheat grass (75W1).

High densities of sheep and cattle in the Interior Columbia Basin destabilized nearly every component of the ecosystem:

[D7a] - Grazing Lands Degradation - Interior Columbia Basin - Idaho -

The steppe-like grassy plains in portions of Idaho and eastern Oregon and Washington are now commonly barren and eroded (p. 65 of Ref. (91J1)).

The Challis Planning unit of the BLM (in Idaho) has 352,000 acres. Soil erosion is rampant. 52% of the area has undergone "moderate" to "severe" soil erosion. Pedestaling, rills and gullies are readily apparent. Widespread is the absence of plant litter to stabilize soils and help germinate seeds (Ref. 47 of Ref. (81S1)).

Quote of Wm. R. Meiners (resource management specialist of 30 years for the USFS, SCS, BIA and BLM) in a court deposition concerning conditions in the 321,000-acre Challis Planning Unit of the BLM on the East Fork of the Salmon River (Idaho): "The public lands of this unit, and particularly those along the East Fork, are among the most abused lands I have ever seen in my professional career. Grazing pressures have reduced the land along the river to almost a bare-ground status. Erosion is evident, topsoil has been lost, meadows have been beaten into the ground." (75W1).

In the Saylor Creek Unit of (Idaho's) Boise Grazing District (1000 mi2), over-grazing has been a major contributor to pollution and sedimentation in Saylor Creek and the Snake River (75W1).

[D8] - Grazing Lands Degradation - Indian Reservation Range lands -

Grazing permits on Navajo rangelands are issued based on range capacities of the 1930s, and have yet to be adjusted to reflect declining range capacity (97W1).

The 15 million-acre Navajo Indian Reservation can safely support 16,000 sheep at most. 140,000 sheep graze there (Ref. 38 of Ref. (81B1)) (77B1).

Locations on the Navajo Indian Reservation described by 19th Century travelers as lush meadows are, today, vistas composed of scattered sod remnants amid shifting sands and deep gullies. Only a small fraction of the potential economic benefit is being harvested from these dusty, sage-brush-dotted lands that were once largely carpeted with grass (78E1). (The Navajo population is growing at 3%/ year (81S3).) In 1937 there were 1.3 million sheep on the Navajo reservation. The carrying capacity then was 600,000 sheep. In 1981 there were 2,170,300 sheep on the reservation (81S3). Comments: Note the wide disparities among these figures. Part of this may be due to expansion of the reservation over time.

[D9] - Grazing Lands Degradation - Great Plains -
Large stretches of the Great Plains are underlain by sand dunes that, in a sufficiently severe drought, could turn into seas of wind-blown sand dunes like those of the Sahara Desert. In the 1930s the dunes were on the verge of becoming active when the drought ended. Wind-blown sand dunes have been seen on the Great Plains within the past few centuries (William K. Stevens, Pittsburgh Post Gazette, 5/28/96).

[D9a] - Grazing Lands Degradation - Great Plains - Montana -
In the Charles M. Russell National Wildlife Range (grazing administered by the BLM) erosion of the bearpaw shale lands has caused significant silt deposition into the Missouri River and encouraged the infestation of sage brush, rabbit brush and greasewood to replace native grasses - all due to over-grazing (75W1).

[D9b] - Grazing Lands Degradation - Great Plains - Texas -

In a large area of west Texas and eastern New Mexico over the past 100 years, large areas of black grama grassland have been replaced by communities dominated by shrubs, especially creosote bush and mesquite (Refs. 12, 13, 14 of Ref. (90S1)). Heavy grazing during the short summer wet season contributes to loss of grass cover during moderate drought and to lowered competitive potential of grasses (Ref. 24 of Ref. (90S1)).

In Gaines Co. Texas, about 25% of the rangeland appears over-grazed (81S1). 10000-15000 acres (40-60 km2) of the remaining natural grassland are plowed annually to plant more cotton. Rainfall (16"/ year) is so low that dryland farming is a losing proposition and subject to much wind erosion (81S1).

Late in 1999, Texas pastures were 88% poor to very poor, according to the state's Agricultural Statistics Service (9B2).

[D9c] - Grazing Lands Degradation - Great Plains -Oklahoma -
In late 1999 Oklahoma's pastures were 38% poor to very poor (99B2).

[D9d] - Grazing Lands Degradation - Great Plains - Kansas -
In late 1999 Kansas' pastures were 26% poor to very poor (99B2).

[D10] - Grazing Lands Degradation - Privately owned Rangeland -

Support for George Wuerthner's statement that private grazing lands are more degraded than livestock-grazed public lands:

Privately owned grazing lands tend to be more productive and better watered than public grazing lands, and thus intrinsically more resistant to grazing abuses (99W1).

Private US grazing lands are in worse shape than public grazing lands. Although 160 million acres (250,000 sq. mi.) of public land are considered to be in unsatisfactory condition, more than 270 million acres (422,000 sq. mi.) of private grazing land are in unsatisfactory condition (99W1).

In 1987 the US SCS reported the condition of private rangeland as: 4% excellent, 31% good, 47%fair, 17% poor (p. 484 of Ref. (91J1)).

In a 1975 BLM survey, 68% of private range was reported in fair or poor condition (87L1).

Changing Condition of Non-Federal Rangelands (80U1)
Year |Excellent| Good| Fair| Poor
1963 | ~5% ~ ~ | 15% | 40% | 40%
1977 | 12% ~ ~ | 28% | 42% | 18%

[D11] - Grazing Lands Degradation - State-Owned Ranch-land -
Condition of state-owned ranch land (34 million acres (138,000 km2) in 1982): 4% excellent, 31% good, 50% fair, 14% poor. Over 64% of state ranch-land is functioning at less than 50% of its potential (p. 479 of Ref. (91J1)).

[D12] - Grazing Lands Degradation - USFS Lands -

Grazing Use and Capacity in USFS Region 3 (AZ and NM) Forests (from a chart)
National|Permitted|Grazing
Forest- |Grazing~ |Capacity
- - - - | (AUM) ~ | (AUM)
Cibola~ | 250,000 | 180,000
Coronado| 390,000 | 320,000
Gila~ ~ | 370,000 | 310,000
Kaibab~ | ~80,000 | ~60,000
Santa Fe| 110,000 | ~70,000
Tonto ~ | 405,000 | 255,000
Source: Jeffrey St. Clair, "New Incentives for Southwestern Forests", Forest Watch Magazine, 12(11) (June 1992)

On Coronado National Forest, the USFS has calculated that its lands are overgrazed by at least 73,000 AUMs (85C1).

Toyabe National Forest contains 3.2 million acres (13,000 km2), with 1.1 million acres classified as suitable for livestock grazing. The USFS reports that another 250,000 acres of unsuitable range is currently being grazed by livestock. 40-45% of Toiyabe rangelands are in poor condition, more than any other US national forest (89U1).

Of the 9200 grazing allotments in the USFS's 6 western regions, range managers have identified almost 2,200 that they consider to be in a declining condition and/or overstocked. 104 million acres of USFS-managed grazing land are divided into 9752 grazing allotments (9217 are in 6 western districts). The USFS has classified about 50 million acres (202,000 km2) within the 104 million acres (421,000 km2) of grazing allotments as suitable for livestock grazing (91D2).

18 of 90 million acres of USFS range were in fair condition or worse (1979) (85R1).

During the 1980s, many USFS plans revealed that grazing continues at levels above USFS estimates of the land's capacity (94O1).

[D13] - Grazing Lands Degradation - Great Basin -
Significant portions of the sagebrush-grass rangelands of the Great Basin (US) have been degraded to where they produce under 50% of their potential (Ref. (84E1) in Ref. (99G1)).

[D13a] - Grazing Lands Degradation - Great Basin - Utah -

In the 520-km2 Monticello Grazing District of southern Utah, the natural ground cover has been almost totally destroyed, leaving desert lands and creating erosion gullies so long and deep that they are often used as roads (75W1).

Of 106 small pastures studied along the Wasatch Front, 44% were over-grazed. (U.S. Utah extension agents James Barnhill, 801-399-8208 and Dean Miner, 801-370-8469, utah@ext.usu.edu, 1997).

[D14] - Grazing Lands Degradation - Water Runoff from Grazing Lands -

Each linear mile of dirt road ruins an average of 4 acres of ecosystem. Accordingly, Western public land's minimum of 500,000 miles of official and de facto ranching roads represents a bare area of 2 million acres (3125 sq. miles) ((91J1) p.223).

Livestock grazing in an non-forested valley in Black Hills National Forest increased summer storm runoff by as much as 60% (75O1) (97B2). With increased runoff, soil erosion increases (54D1) (97B2).

Grazed pastures in a ponderosa pine/ bunchgrass range lost 3-10 times more sediment than ungrazed pasture (67S1) (See Ref. (97B2)). Comments: This may not be very useful, because sediment loss from ungrazed pasture is extremely small.

Summer rainstorms on grazed sub-alpine hillsides accounted for 53-85% of sediment loss. Following elimination of livestock from the watershed, vegetative cover increased 150%, the proportion of annual runoff from summer rainstorms dropped 72%, causing a corresponding 50% drop in sediment loss (31F1) (97B2). Comments: The above material was also put in the soil loss review.

[D15] - Grazing Lands Degradation - Exotic Species Effects -

An estimated 500 million plants are imported to the US each year (10M1).

Today, about 30 new invasive insects are discovered annually in the US (10M1).

The yearly impact of invasive species in the US is estimated at $133.6 billion based on a study by the Agricultural and Resource Economics Review of 2006 (10M1).

An estimated 50,000 plant, animal, and insect species have been introduced into the U.S. throughout its history (10M1).

Alien invasive species such as weeds or rats may be causing $1.4 trillion damage per year to the global economy. (This is almost 5% of the world economy.) Alien species are spread via global agriculture, horticulture, pet trades, and in the ballast water of ship hulls (09D1). (Comments: on western rangelands, overgrazing is a major cause of invasive plant species. Some of them are toxic to cattle.

Invasive species include insects, fungi, algae and other plants or animals. Agricultural weeds are the No.1 danger; rats are the No. 2 danger (09D1).

South Africa has an active invasive species eradication program (09D1).

New Zealand has imposed tough customs controls to reduce the spread of invasive species (09D1).

Water hyacinth is a native of the Amazon basin, but it exploded in Africa since it was bought there as an ornamental plant. In Uganda, the hyacinths cause $112 million / year by forming a floating mat choking parts of Lake Victoria since 1990 (09D1).

In sub-Saharan Africa, the invasive "witch weed" causes annual maize losses totaling about $7 billion/ year (09D1).

In Europe, a program to curb invasive species, DASIE, estimates that there are more than 11,000 invaders. Some 15% of these cause economic damage (09D1).

North Dakota has 1.1 million acres (4450 km2) of grazing land affected by leafy spurge (vs. 932,000 acres in 1991). Leafy spurge crowds out prairie grass, rendering pastures useless (Wall Street Journal, 6/15/99).

An extensive scientific literature going back many years (i.e. (51P1), (81M1), (87L2), (90L2), (94Y1), and others cited in Sheley (94S1) (see Ref. (97B3)), suggests that livestock grazing is the major cause of the spread of weeds in rangelands in the western US. Livestock disturb the soil, create micro-sites for weed seed germination, increase soil temperatures, pulverize microbiotic crusts that prevent the establishment of weeds, reduce the vigor and competitive ability of native plant species, and transport weed seed from infested areas into non-infested areas. One study, for example, found that one cow transported over 900,000 viable seeds from 36 different weedy species in her gut and coat in a single season (42D1) in Ref. (97B3)).

In the intermountain West (US), exotic forbs have invaded over 400,000 km2 of rangeland (99G1).

Long-term monitoring suggests that some weed-altered arid communities may never recover, even with cessation of all disturbances ((90B2) in Ref. (99G1)).

Arid portions of the Pacific Northwest have been invaded by over 860 exotic plant species, over 40% of the estimated 2000 exotic plants currently recorded in the entire US. (See Ref. (99G1)) Of these, 115 have been declared "noxious weeds" by one or more states (99G1).

The spread of exotic weeds throughout the grasslands, shrublands, woodlands and shrub-steppe of the Intermountain West has been described as one of the greatest environmental threats facing native species and ecosystems of the region (89M1), (90B2), ((98W1) in Ref. (99G1)).

One of the most devastating consequences of weed invasions in the Intermountain West may be the absence of community recovery once flammable weeds produce a permanently shortened fire-return cycle (78Y1), (90B2), (90W2) in (99G1).

In a study of 600 rangeland sites in Utah, 17% of plant species were exotics in sites lacking microbiotic crusts, while 10% of species were exotic in sites with intact crusts (99G2) in Ref. (99G1)).

Tramples grassland in a Washington State study was invaded by exotic species, while nearby non-trampled grasslands were not ((85R3) in Ref. (99G1)).

Exotic plants in a trampled Utah site were nearly 5 times as numerous, and had over 20 times greater cover than an undisturbed site (95B1 in Ref. (99G1)).

The most invasible communities for exotic plants are those with low average levels of plant cover and frequent disturbance (83C4), (89R2) in (99G1).

[D16] - Grazing Lands Degradation - Juniper -

(Pinyon-Juniper Dynamics: ) (Over)Grazing is the primary cause of grasslands being converted to pinyon-juniper. By removing understory fine fuels on what are already sparsely vegetated lands within pinyon-juniper zones, it provides more fire suppression than all the firefighters combined. The removal of the native understory of perennial grasses and forbs by overgrazing also opens the site for juniper seedling establishment. Juniper have a tough time getting established in undisturbed native grasslands and steppe. A recently germinated juniper cannot compete with established bluebunch wheatgrass for water. Young junipers do not develop drought-tolerance until later in life. (Continued)

Most juniper that manage to get established actually do so in the micro-climate under a sagebrush nurse plant (or bitterbrush in some areas) in a deteriorated area. Robins are the primary biological dispersal agent for juniper. They eat juniper berries, perch on sagebrush plants, and poop undigested juniper seeds in capsules of fertilizer. (Continued)

Mature sagebrush (big enough for a robin to perch on) have few "feeder" roots near the surface within the area covered by their canopy, they draw their water from deeper and with spreading roots beyond the canopy "drip" line. (This is the case with many woody plant species.) When you factor in shading, reduced air movement, and stem flow of intercepted precipitation; the surface of the soil underneath a sagebrush plant's canopy is usually moister than the surrounding area. If the area under the canopy of the sagebrush is well occupied with herbaceous vegetation, mosses, lichens, and biological crust (in other words non-grazed), that moisture has already been spoken for, and the juniper seed will probably not be able to become establish. If the area immediately under the canopy is not well occupied, then the juniper seed has enough water available to germinate and establish itself, and the sagebrush serves as a nurse plant until the juniper is large enough that the sagebrush plant can no longer compete (for both water and light) and dies. (Larry Walker "Relation between pinyon/juniper invasion and overgrazing," (7/16/00))

Ref. (96D1) concludes, "over the time scale that encompasses much of the pinon-juniper woodland expansion in the western US, tree-induced heterogeneity in soil morphology is minimal and, alone, is not a significant factor in initiating or controlling soil erosion."

Roughly 50% of the pinon-juniper woodlands in the US were established in the past 150 years. (96D1) (81T2) Comments: This statement appears to contradict the statement that pinon-juniper woodlands have increased as much as 5-fold during the past 150 years.

Pinon-Juniper woodlands have increased as much as 5-fold during the past 150 years, and currently occupy 200-300,000 km2 throughout the western US (96D1) (94M1).

Ref. (96B2) cites studies that found that an increase in herbage production after tree removal does not necessarily result in improved range conditions. (Low quality annual weeds often result, rather than perennial grasses.)

Excessive rates of runoff and sediment production in pinyon-juniper woodlands are blamed on overgrazing and other human uses, since herbaceous cover is significantly lower in grazed than in ungrazed woodlands (88E1), (90M1).

Rapid reinvasion by trees after conversion, and studies showing that anticipated increased water yields and reduced erosion did not materialize led to a reduction or total abandonment of conversions of pinyon-juniper-dominated areas of the West back to grasslands (74C2) (84W1) (87D1).

USFS, BLM and USFWS surveys show that approximately 5% of eastern Oregon is currently, or will potentially be, affected by juniper encroachment (96B2).

[D17] - Grazing Lands Degradation - National Parks and Similar Lands -

On many US national wildlife refuges, grazing and haying occur with the rationale that these practices will benefit wildlife. Upon review of 123 refuges, Strassman (87S2) concluded, "although in theory cattle grazing and haying can be wildlife management tools, as implemented they are tools that do more harm than good".

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SECTION (4-E) - Grazing Land Degradation - South- and Central America - [1] General, [2] South America, [3] Central America,

[E1] - Grazing Lands Degradation in Latin America - General -

Latin America's major rangelands includes:

These rangelands require 15-50 km2 to support 100 cows (2-6 AU/ km2). They are often over-grazed in terms of producing soil erosion and non-forage weeds (p. 113 of Ref. (90W1)).

[E2] - Grazing Lands Degradation - South America - [E2a] Argentina, [E2b] Bolivia, [E2c] Brazil, [E2d] Chile, [E2e] Colombia, [E2f]~ Peru, [E2g]~ St. Helena Is. , [E2h] Uruguay,

A massive cropland expansion is now taking place in the Brazilian Amazon Basin in the Cerrado, a huge savannah-like region bordering the Amazon basin on its south side. Land in the Cerrado is like that in the U.S. semi-arid plains where the "Dust Bowl" took place, and in the semi-arid region of Kazakhstan where the massive Soviet expansion (and subsequent abandonment) of wheat acreage occurred. The Cerrado region is vulnerable to soil erosion via wind erosion like virtually all semi-arid plains. This cropland expansion is pushing cattle ranchers into the Brazilian Amazon forests, where ecologists are convinced that continuing to clear the area of trees will end in disaster. Reporter Geoffrey Lean, summarizing the findings of a 2006 Brazilian scientific symposium in London's Independent, notes that the alternative to a rainforest in the Amazon Cerrado would be "dry savannah at best, desert at worst." (10B1).

Some 17.7% (166,000 km2) of the 937,000 km2 of Brazil's semi-arid region are desertified, according to research by the Federal University of Ceara. Brazil's semi-arid region occupies 9.3% of Brazil, and is concentrated in northeastern Brazil (Marco Bahe, "Brazil loses US$800 million/ year with desertification," Brazil-Arab News Agency, 6/13/06.).

In Brazil, some 580,000 km2 of land are affected by expanding deserts. Economic losses from desertification are estimated at $300 million/ year, much of it concentrated in Brazil's northeast (06B1). (su3)

[E2a] - Grazing Lands Degradation - South America - Argentina -

Desert-like lands are being created in Argentina's states of LaRioja, San Luis and LaPampa (76E1).

For decades, sheep have over-grazed Patagonia's rangelands of lower Argentina - 900,000 km2 grazed by 16 million sheep (18 sheep/ km2) (3.6 AU/ km2) (90W1).

Patagonia (southern Argentina) was settled in the 19th century. Its sheep ranches helped make Argentina one of the world's wealthiest countries. But decades of over-grazing have turned Patagonia into a barren plateau reminiscent of South Dakota (94N1).

The 1 million km2 Gran Chaco in Argentina, Paraguay and Bolivia, have turned to thorny shrubs from over-grazing. Carrying capacity: 5-50 cows/ km2 (p. 117 of (90W1)).

Dry Chaco rangeland (Argentina) is degraded by shrub-invasion and salinization. Patagonia (Argentina) grasslands are over-grazed by sheep (90W1).

[E2b] - Grazing Lands Degradation - South America - Bolivia -

The 170,000 km2 Antiplano of Bolivia, and the Puna of Peru are among the richest, most productive ranges in the world. They have endured centuries of over-grazing since Spanish colonization (p.117 of Ref. (90W1)).

Over-grazing in Bolivia dates back to Spanish colonization; most Bolivian rangelands are affected by soil erosion (90W1).

The natural grasslands of Bolivia's Altiplano highlands are in surprisingly good condition, considering the region's history of over-grazing (90W1).

[E2c] - Grazing Lands Degradation - South America - Brazil -

The Coatingo in northeastern Brazil covers 800,000 km2 of thorn-scrub vegetation. It supports a large portion of Brazil's cattle and a large goat population. Centuries of over-grazing, fire, agriculture and torrential rains have seriously eroded the shallow soil on most of the Coatingo (p. 116 of Ref. (90W1)).

50% of Brazil's cattle herd is supported on savanna, where poor forage quality in dry seasons limits yield (90W1).

Thorn-scrub rangeland in northeast Brazil is over-grazed by goats and cattle, and has suffered soil erosion and salination (90W1).

Forest-derived pasture in the Amazon Basin is productive for fewer than 10 years because of soil infertility (90W1).

In Brazil, desertification affects nearly 400,000 square miles (Seattle-PI-Com Desertification, 11/23/99).

Conversion to pasture of up to 430,000 km2 of Amazon rainforest over the past three decades caused rapid decline of productivity and land abandonment after 4-8 years of use (Ref. 43 of Ref. (95D2)).

[E2d] - Grazing Lands Degradation - South America - Chile -

Southward encroachment by the Atacama Desert plagues northern Chile. A decade-long drought there in the 1960s was accompanied by desert advancement of 116 mi2 (300 km2)/ year (76E1).

[E2e] - Grazing Lands Degradation - South America - Colombia -

Colombia, according to Colombian environmentalists, is converting forestland to pasture at 4000-6000 km2/ year. (LanceOlsen@aol.com 10/18/99) Comments: This information is also in deforestation review document.

Savannas in Orinoco Basin (Colombia) have low rates of cattle production. Forest-derived pastures in Amazon Basin are short-lived and subject to weed-invasion. Pastures of voluntary grasses support cattle at low grazing densities (90W1).

[E2f] - Grazing Lands Degradation - South America - Peru -

The foothills of the western Andean range are bare, and support only a thin grass cover during sporadic rainfall periods. That cover is depleted rapidly by grazing sheep. Sporadic rains cause gullies and landslides, often resulting in property damage and death, and cutting the road linking Lima with the central Sierra (90H3).

[E2g] - Grazing Lands Degradation - South America - St. Helena Island -

When St. Helena (an island 10 miles x 6 miles in the South Atlantic ocean) was discovered by the Portuguese in 1501 there were no indigenous mammals, so goats were immediately introduced. By 1588 2/3 of the island's topsoil was washed out to sea, and much of the vegetation was irretrievably destroyed. Fencing and grazing restrictions did not come until the late 17th century, and there was little practical done for species conservation until recent times (95G1).

[E2h] - Grazing Lands Degradation - South America - Uruguay -

Weed-infestation is common in natural grasslands, notably in Chaco region (90W1).

[E3] - Grazing Lands Degradation - Central America -

Mexico has a much larger fraction of arid and semiarid land than Brazil. That land is vulnerable to expanding deserts. Mexico's degrading cropland now prompts 700,000 Mexicans to leave the land each year in search of jobs in nearby cities or in the US (06B1).

In Central America, many pastures on previously forested land are rapidly degrading. Pastures planted on rich coastal soils have low forage quality (90W1). Comments: Tropical grazing lands created from forestlands last 5-10 years before they must be abandoned for about 30 years to allow soil fertility to recover.

[E3a] - Grazing Lands Degradation - Central America -Costa Rica -

Cultivated pastures occupy up to 76% of Costa Rica's land suitable for annual crops. Pastures in Costa Rica on infertile lands with sharp relief are short-lived and provoke severe erosion (90W1).

[E3b] - Grazing Lands Degradation - Central America -Dominican Republic -

Over-grazing is common in cattle pastures that are part of large estates in Dominican Republic. Dry forest lands are used as open range for goats that reduce tree cover (90W1).

[E3c] - Grazing Lands Degradation - Central America -Haiti -

Dry forest rangeland in Haiti is degraded, but is the basis of subsistence-level goat-production (90W1). Lowland cattle pastures are poorly managed and unproductive (90W1).

[E3d] - Grazing Lands Degradation - Central America -Mexico -

Capacity of Mexico's rangelands is 4.5-9 cows/ km2, but average livestock density is 17-33 cows/ km2. Over-grazing has caused serious soil erosion (Refs. 97, 98 of Ref. (90W1)).

Most rangelands in Mexico are severely over-grazed (90W1).

Grazing-provoked soil erosion is common in dry regions of Mexico; erosion and hydrologic changes follow forest conversion to pastures, particularly on steep slopes (90W1).

Goat/sheep grazing on dry range in Mexico is reducing tree cover and increasing soil loss (90W1).

Weed invasion limits range productivity in dry regions of Mexico (90W1).

Grazing in pine/ oak highlands is reducing forest regenerative capacity in Mexico (90W1).

In the savannas of northern and central Mexico, livestock density is nearly four times the land's carrying capacity (Ref. 47 of Ref. (91D1)).

A comparison of livestock populations reported in the 1960 census from Coahuila (in Mexico) with the potential carrying capacity under "good" conditions of vegetation indicates that close to 50% general overstocking exists (70X1).

Baja California, San Benito Islands (Mexico), and California's San Clemente Island have been converted to wastelands by goats (p. 357 of Ref. (91J1)).

Mexico's communal tenure system followed the 1910 revolution. Ejidas (where poor people graze their animals) currently occupy 250,000 km2 in northern Mexico. In one 21,000-acre (85-km2) ejida, proper stocking is 387 AU (782 if it were in excellent condition). Actual stocking is 1100 AU (86L1).

SECTION (4-F) - Grazing Land Degradation-Europe, Australia, Oceania - [F1] Australia, [F2] New Zealand, [F3] Europe,

[F1] - Grazing Lands Degradation - Australia -

I know of at least one instance where grazing impacts are clearly visible on satellite imagery. It was one of the most dramatic illustrations of grazing induced environmental damage that I have ever seen. It contained a color satellite image of Australia that showed regularly spaced measles-like dots in southwestern Australia. Those "measles" were the impacts of grazing on "free-holds" (kind of the Australian equivalent of homesteads). Other photos showed the really massive sheet (and gully) erosion that those measles represented (Larry Walker lwalker@rangebiome.org 10/15/01).

During periods of low profitability, Australian grazers tend to offset low returns per animal by increasing their flocks and herds (p. 316 of Ref. (70P2)).

Some 56% of Australia's arid and semi-arid plains have suffered vegetation shifts, and 13% is severely degraded (Ref. 50 of (91D1)).

In Western Australia, about 1/3 of pastoral lands is over-grazed (83C2).

[F2] - Grazing Lands Degradation - New Zealand -

In large portions of New Zealand's North Island, "slips" (huge slabs of topsoil) are sliding off over-grazed hills (p. 357 of Ref. (91J1)).

Instability of soil in some parts of New Zealand, notably in foothills of mountains bordering South Island's Canterbury Plains, in Whangamomona County, and the Gisborne district of North Island has no equal in world in terms of accelerated erosion. Much of the accelerated erosion is due to over-grazing by sheep, particularly in New Zealand's South Island (75S1).

Over-grazing has produced almost complete destruction of vegetation on parts of Torlese Range and in Craigieburn Mountains of Canterbury, as well as in other parts of New Zealand's North- and South Canterbury (75S1).

[F3] - Grazing Lands Degradation - Europe -

Some 31% of Spain is threatened with conversion to desert (04H1).

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