Overall it is estimated that close to 50% of the world's mangrove forests have been destroyed (95K1).

More than 50% of the world's mangroves have been lost in recent decades (00M1).

Loss of mangrove forest results in increased sediment transport onto downstream coral reefs (Ref. 37 of Ref. (00N1)).

Shrimp are often produced by clearing coastal mangrove forests that protect coastlines and serve as nurseries for local fish. Mangrove destruction can cause a decline of local fisheries that will actually exceed the gains from shrimp production, leading to a net protein loss (00W2).

There are plans to establish a 100 km² shrimp farm in the Rufiji Delta of Tanzania, an area containing 530 km² of mangrove forests (01M2).

The Cayapas-Mataje Mangrove Reserve in Ecuador contains 530 km² on the border with Colombia. Ecuador's other mangrove area is Muisne where 250 km² of mangroves have been reduced to 6 km² (00M1). (la)

New legislation in Brazil bans farming in mangrove swamp areas and stipulates that shrimp farmers must obtain environmental licenses to operate ("Shrimp farming banned in mangroves" (Brazil) www.FIS.com (10/25/02)).

Today there are about 50 km² of shrimp farms in Brazil, some built directly in mangrove areas (01M2). Expansion to 300 km² in 3 years is planned (01M2).

The Brazilian government proposes to allow 10% of Brazil's mangroves to be cut for shrimp-pond development (01M2).

Brazil contains the second-largest mangrove area in the world. Possibly over 10,000 km² of mangrove forests are found along Brazil's coastline (01M2). (la)

The Indus delta region contains the world's fifth-largest mangrove forest. This forest is deteriorating markedly from rising salinity, decline of nutrients, erosion and land subsidence. (R. Leichenko, James L. Wescoat Jr., "Environmental Impacts of Climate Change and Water Development in the Indus Delta Region", Water Resources Development, 9(3) (1993)) (su5)

The protective reefs, sand dunes and mangroves that look out to the Indian Ocean in a broad arc from Sri Lanka to Bangladesh and Indonesia have been dynamited and bulldozed (04B1).

When the tsunami struck India's southern state of Tamil Nadu on 12/26/04 areas in Pichavaram and Muthupet with dense mangroves suffered fewer human casualties and less damage to property compared to areas without mangroves. In October 1999, mangrove forests reduced the impact of a 'super-cyclone' that struck Orissa on India's east coast, killing at least 10,000 people and making 7.5 million homeless. Those human settlements located behind healthy mangrove stands suffered little, if any, losses ("Loss Of Mangrove Forests Contributed To Greater Impact Of Tsunamis", Mangrove Action Project, 1/4/05, PO Box 1854, Port Angeles, WA 98362-0279 (360-452-5866) mangroveap@olympus.net www.earthisland.org/map).

India laid waste to as much as 50% of its mangroves during 1963-1977 (04B1).

The Sundarbans Reserve Forest of Bangladesh covers 6017 km² of mangrove forests, wildlife sanctuaries, sandbars, rivers and canals (00M1).

In the Philippines, 2,500 km² of mangrove (more than half the area that existed 80 years ago) has been destroyed. Some 60% of this loss is attributed to coastal culture of prawns and milkfish (03U2).

In Myanmar's (Burma's?) Irrawaddy Delta, the region ravaged by the cyclone of 5/2/08 vast swaths of mangroves had been cleared over the decades to make way for rice fields and shrimp farms and to provide wood for fuel. Mangrove forests used to serve as a buffer between the rising tide, big waves and storms and the residential area. Mangroves, with dense network of trees and shrubs that live in tropical tidal zones, line 25% of the world's tropical coastlines. But in Asia they have been uprooted to create farmland, aquaculture farms and urban developments. About 83% of the mangroves in the Irrawaddy Delta were destroyed during the period 1924-1999 (08S1).

Destruction of mangroves was begun by British colonial authorities that encouraged rice cultivation in the delta that was once known as the "rice bowl" of the world. In other parts of Asia, the greater spoiler of coastline mangroves is shrimp farms. This is because Thailand, Indonesia and India have become some of the world's biggest shrimp exporters. Shrimp farms demand brackish waters and flat land. Both are common where mangroves commonly grow (08S1).

People in the city of Rangoon cannot afford propane or gas, so mangroves are harvested for firewood (08S1).

Mangroves have also been converted to agricultural lands. However this causes residents to move closer to the sea and to build homes in areas with high risks of destruction due to the actions of the sea. Many villages in Myanmar are in rice-growing areas that are below sea level (08S1).

The protective reefs, sand dunes and mangroves that look out to the Indian Ocean in a broad arc from Sri Lanka to Bangladesh and Indonesia have been dynamited and bulldozed (04B1).

Thousands of km² of mangroves and coastal wetlands have been transformed into milkfish and shrimp ponds in Southeast Asia (00N1). In Southeast Asia, mangrove-dependent species account for roughly 1/3 of wild fish landings excluding trash fish. A positive relationship between finfish and shrimp landings and mangrove area has been documented in Indonesia, Malaysia and the Philippines (Refs. 32-34 of Ref.(00N1)). Mangroves are also linked closely to habitat conditions of coral reefs and seagrass beds (Refs. 35 and 36 of Ref. (00N1)).

In Indonesia, Java has lost 70% of its mangrove area, Sulawesi 49%, Sumatra 36%. Globally the rate of decline in mangrove forest cover is 2-8%/ year, said the paper (The Mangrove News, 149th Edition, 1/16/05 Alfredo Quarto mangroveap@olympus.net).

In Indonesia's Aceh province, devastated by the tsunami of 12/26/04, mangroves are being harvested as timber for sale to Malaysia and Singapore (04B1).

Shrimp farming alone caused a loss of 65,000 hectares of mangroves in Thailand, according to a 2002 paper by V. P. Upadhyay and colleagues in the journal Current Science (The Mangrove News, 149th Edition, 1/16/05 Alfredo Quarto mangroveap@olympus.net).

During 1975-1993, Thailand's mangrove area was almost halved (statement by Edward Barbier, editor of a recent book on Asia's disappearing mangrove systems.) (04B1).

Over 80% of Vietnam's mangrove forests have been lost ("World Bank Says Vietnam's Environment is Rapidly Deteriorating", Associated Press (9/18/02)).

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SECTION (7-B) ~ CORAL REEFS ~ [B1]~Values, [B2]~Global, [B3]~Damage Mechanisms, [B4]~Africa, [B5]~Arabian Sea, [B6]~Australia, [B7]~Belize, [B8]~Caribbean, [B9]~Costa Rica, [B10]~Florida, [B11]~Indonesia, [B12]~Jamaica, [B13]~East Asia, [14]~Philippines, [15]~Singapore, [16]~South America, [17]~South Pacific, [18]~Indian Ocean, [19]~Oceania, ~

Hundreds of millions of people worldwide - by some estimates, 1 billion across Asia alone - depend on coral reefs for their food and their livelihoods. (Data of the International Union for the Conservation of Nature (IUCN data of 2008))

Reefs harbor at least 25% of all marine life. About 10% of the world's fisheries come from reefs, and much of this feeds protein-starved people in under-developed countries (01R2).

Officials in the Maldives (off the southwest coast of India) said extensive (coral) reefs (500 miles in length according to James Hookway, Wall Street Journal (12/30/04), p. A7) smothered the tsunami of 12/26/04 (04B1).

While covering less than 1% of the Earth's surface, coral reefs provide the planet with $375 billion in economic benefits globally (yearly??) (04H1).

(general) According to one estimate, coral reefs provide goods and services worth about $375 billion/ year - a staggering figure for an ecosystem that covers less than 1% of the earth's surface (02M2). Comments: Somewhere else is a statement that coral reefs cover under 0.1% of the world's oceans.

(habitat) Coral reefs anchor many marine ecosystems; their loss could mean extinction for thousands of species of fish and other marine life (00V1).

(food) In developing countries, coral reefs contribute about one-quarter of the total fish catch, providing food to an estimated one billion people in Asia alone (02M2).

(food) About 500 million people rely on (coral) reefs for food and income (00V1).

(food) Fisheries capture from reefs contribute 10% of the fish for human consumption globally, and a far larger fraction in developing nations (Ref. 37 of Ref. (00N1)).

By 2004, an estimated 20% of the world's coral reefs had been destroyed (up from 11% in 2000), an additional 24% of the world's coral reefs were close to collapsing, and another 26% were under long-term threat of collapse. (NOAA data of around 2008)

Some 50% of the Caribbean's corals are already dead, largely because of climate change, over-fishing and pollution (NOAA data of around 2008).  

At least 19% of the world's coral reefs are gone, including some 50% of those in the Caribbean.
An additional 15% of the world's coral reefs could be dead within 20 years (Data of the National Oceanic and Atmospheric Administration NOAA).

Status of coral reefs by sub-region in 2004 (p.253) (from a chart) (Areas are in thousands of km²) (07A2)

Areas with Tracts of Particularly Devastated Reefs (93W2)

Part [B3] ~ Key Habitats/ Inventories/ Degradation ~ Coral Reefs ~ Damage Mechanisms ~

Although the US and many other countries forbid using cyanide and explosives to stun fish, these methods are still widely practiced in the South Pacific and Southeast Asia (01R2). Comments: This practice is apparently carried out mainly in reef areas.

Sources of Information on Coral Reef Degradation (02M2):
Barber, C. V., and V. R. Pratt, "Sullied seas: Strategies for combating cyanide fishing in Southeast Asia and beyond", World Resources Institute, Washington, DC (1997).
Bryant, D., L. Burke, J. McManus, and M. Spalding, "Reefs at risk: A map-based indicator of threats to the world's coral reefs", World Resources Institute, Washington, DC (1998).
Clark, A. M., and D. Gulko, "Hawaii's state of the reefs report, 1998". Department of Land and Natural Resources, Honolulu, Hawaii.
Dayton, P., Reversal of the burden of proof in fisheries management. Science 279: (1999) pp.821-822.
Green, E., and F. Shirley, "The global trade in coral", WCMC Biodiversity Series No.9. World Conservation Monitoring Centre. World Conservation Press, Cambridge, UK (1999).
Hodgson, G., A global assessment of human effects on coral reefs. Marine Pollution Bulletin. 38(5): (1999) pp. 345-55.
Roberts, C., "Effects of fishing on the ecosystem structure of coral reefs", Conservation Biology 9(5) (1995) pp. 989-92.
Wilkinson, C. (editor), Status of the coral reefs of the world: 2000. Global Coral Reef Monitoring Network and Australian Institute of Marine Science, Cape Ferguson and Dampier, Australia. (http://www.aims.gov.au/scr2000).

(general) Coral reefs are in serious trouble worldwide from a powerful combination of stresses that are threatening their survival, including: overexploitation of resources for subsistence and commercial fishing; destructive fishing practices that degrade and destroy the habitat itself; increasing coastal populations, which are expected to double in the next 50 years; poor land use practices and runoff of pollutants, sediments and nutrients; disease outbreaks, which may be associated with poor water quality and pollutants; coral bleaching, associated with increasing seawater temperatures and global change; and removal of coastal mangrove forests (02M2).

(general) Global warming damages the coral by bleaching, a process in which the reefs heat up and expel the microscopic plants that give them their color (00V1).

(fishing practices) Various explosives, such as dynamite and homemade bombs, are also used to kill fish for easy collection, but at an enormous cost to the reef that is reduced to rubble. In Komodo National Park in Indonesia, about half of the coral reefs have been destroyed through the use of explosives, forming beds of coral rubble that can extend several football fields in length. While the use of explosives to collect dead fish is usually for domestic trade, some of the fish that are only stunned will enter the international trade stream (02M2).

(fishing practices) International trade in wild coral reef animals and products impacts reefs primarily through over-fishing and destructive fishing practices. Live fish for both the food trade and marine ornamental trade are often caught with the use of cyanide or other poison, which temporarily stuns the fish for easy collection. Cyanide use is a serious threat to some of the world's richest coral reefs, as the cyanide kills corals and many other coral reef organisms. The lucrative and unregulated international trade in reef fishes drives the use of cyanide. It is estimated that since the 1960's, more than one million kilograms of cyanide has been squirted onto Philippine reefs alone, and the practice has spread throughout East Asia and the Indo-Pacific (Bryant et al., 1998 in (02M2)).

(fishing practices) In some regions, fishermen use dynamite or cyanide poison, which harms reefs. In other areas, governments allow untreated sewage and other wastes to flow directly into the oceans (00V1). Comments: This cuts off sunlight that is essential to reef survival.

(ocean warming) A leading marine biologist has predicted that global warming will destroy most of the planet's coral reef's by 2050 and "there is nothing we can do to save them". The world's oceans now warm at 1-2 degrees Celsius every 100 years, the loss of the coral reefs will leave many of the fish and eels that inhabit them "homeless, and many species will die out." (Reuters, 9/7/01).

(ocean warming) Scientists at the 9th International Coral Reef Symposium have warned that more than 25% of the world's coral reefs have already been destroyed by pollution and global warming" with the rest to follow in 20 years "unless urgent measures are taken. Hardest hit are some areas of the Indian Ocean where 90% of coral reefs have been killed by water temperatures that rose by up to 6 degrees during the last El Nino event (AP, 10/23/00). Comments: These statements probably refer to shallow-water coral, not deep-water coral.

(ocean warming) Tropical waters in the Northern Hemisphere are heating at a higher rate than other waters, threatening coral reefs. Scientists from National Oceanic and Atmospheric Association discovered that tropical waters above the equator are heating at 1^oF/ decade, 10 times the global rate. Scientists think the increased water temperature is the cause of coral bleaching over the past decade. Coral bleaching would devastate invertebrates and other organisms living in coral reefs (ENN/ Associated Press, (7/29/00)).

(over-fishing) The live food fish trade through Hong Kong alone is estimated to have a retail value of about one billion dollars/ year. Some species of fish, selected live from a restaurant tank; can sell for almost $300/ plate. The global retail of marine ornamental fishes and aquarium hobby supplies is estimated at $500 million/ year. In 2001, for example, a pair of rare fish sold for over $5,000 each. Over 1000 different species of coral reef animals are now traded for marine aquaria (02M2).

(over-fishing) In addition to destructive practices, international trade is driving over-fishing and the selected removal of key groups from coral reefs. Major groups targeted for trade are: groupers and wrasses for the live food fish trade; dead fish and invertebrates for food, medicinal products, and ornamentals including sharks, sea cucumbers, sea stars, mollusks and sea horses; live fish, coral and other invertebrates for marine aquaria and the ornamental hobby; and "live rock" or the calcareous base of the reef for marine aquaria (02M2).

(over-fishing) While coral bleaching may be one of the largest threats facing coral reefs, international trade is having significant impacts on even the most remote and pristine reefs. Recent surveys of reefs worldwide found that many species of high commercial value were absent, or present in very low numbers, in almost all the reefs surveyed (Hodgson, 1999, in (02M3)). Results suggest that almost all coral reefs have been affected by over-fishing, and that there may be no pristine reefs left in the world (02M2).

(pollution) Some 25% of the world's coral reefs have been destroyed by pollution and global warming. Most of the remaining reefs could vanish in 20 years, unless immediate measures are taken (00V1).

(coral harvesting) The US was consistently the largest importer of live coral during the 1990s, importing over 80% of the live coral and 95% of the live "rock" or reef base. Ironically, the US prohibits the collection of coral and live rock in its own waters as they are considered essential fish habitats. In addition to coral, the US imports nearly half (8 million) of the total worldwide trade in aquarium fishes (15-20 million/ year). Many of the fish imported for the marine aquarium market in the US are captured with the use of cyanide and other poisons, which kills non-target animals and the coral reef itself. Sustainability concerns will only increase with the growing international trade. The international trade in coral and live rock to supply the aquarium trade has increased at a rate of 12-30%/ year since 1990 (02M2).

Some 65% of the Persian Gulf's coral reefs have been destroyed (04H1).

Australia's Great Barrier Reef is about 92,000 square miles in size (01R2).

Some 38% of the coral reefs off Southeast Asia have been destroyed (04H1).

A few decades ago, Indonesia was a coral Eden," said the chairman for aquatic biology at the California Academy of Sciences in San Francisco. "Today, it has been utterly destroyed by fishermen using dynamite and cyanide, except for a few reserves and resorts where you literally have armed guards patrolling the reefs" (02D2).

Some 96% of Vietnam's coral reefs are severely threatened ("World Bank Says Vietnam's Environment is Rapidly Deteriorating", Associated Press (9/18/02)).

In northern Jamaica, it is estimated that almost all of the coral reefs are dead or severely degraded from over-fishing and coastal runoff (02M2).

In the Philippines, degraded coral reefs and fish populations have led to an 18% decrease in the amount of protein in the average diet (02M2).

Coral reefs in Morrocoy National Park (Venezuela) turned gray and died four years ago, probably due to toxic wastes dumped by ships.
(See "Poor Protection Allows Destruction of Venezuela's Exotic Wildlife" (12/23/99) AP.

In Sri Lanka, lime is made by burning coral in kilns. Replacing the infrastructure lost in the tsunami of 12/16/04 is expected to massively increase the demand for lime there (05B1).

Some 45% of the coral reefs off South Asia have been destroyed (04H1).

Up to 90% of Indian Ocean coral reefs have been killed because of rising water temperatures in the Maldives and Seychelles islands in the Indian Ocean (00V1).

In Hawaii at Honaunau, the top ten aquarium fish species have decreased by 59% over the last 20 years, and at Kona the most popular aquarium fish show declines in abundance from 38-57%. Even under ideal conditions, it would take more than a lifetime for some coral reefs to recover (02M2).

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SECTION (7-C) ~ ESTUARIES and COASTAL WETLANDS ~ [C1]~Value, [C2]~Global, [C3]~US, [C4]~China, [C5]~Europe, [C6]~First World, [C7]~Southeast Asia, [C8]~Middle East, ~

Some 90% of marine life is found in the world's surface and coastal waters (08G1).

In estuaries and coastal waters, 85% of the large whales and nearly 60% of the small ones have disappeared (08G1).

Coastal zones occupy less than 15% of the Earth's land surface, but they accommodate more than 60% of the world's population (99E1) (07A1).

Coastal systems provide many important services to humans such as nutrient cycling, food production, provision of habitat/ refugia, disturbance regulation, natural barriers to erosion, control of water quality, and nursery grounds. The global value of services derived from sea grasses, estuaries and coastal wetlands is estimated to be 10 times greater than that of any terrestrial ecosystems (97C2) (07A1).

Pollution, eutrophication, drainage, conversion to agriculture and aquaculture, changes in sedimentation and hydraulic regimes, changes in sea levels, global warming, invasive species, fishery over-exploitation and disruptive fishing techniques, urban development, shipping, tourism and water sports are generally considered the most serious threats to present-day coastal wetlands (e.g., (93D2), (00W4), (02K2), (05H1) (07A1).

An additional benefit of a healthy salmon population has been recently documented - the ability of salmon to recycle nutrients from the ocean back upstream. A recent study published in the journal Fisheries has found that the carcasses of salmon return large volumes of organic material to the headwaters of watersheds, feeding insects, bears, plants, and baby salmon. But the depletion of salmon habitat has reduced this flux to 5% of the historical biomass, depleting these nutrient- deficient ecosystems of a large source of nutrients. (Continued below)

Historically, salmon management has been based on the maximum harvest that allows enough fish to return and replenish native streams. This calculation ignores the value of the nutrients in the upbound salmon, thereby depleting the headwaters of its natural nutrient fix. "We have essentially starved our freshwater systems,'' said Bob Bilby, a fisheries scientist with the National Marine Fisheries Service in Seattle. (Continued below)

The researchers utilized equipment that identifies the isotopes of carbon, nitrogen and phosphorous, and thus can track the source. Leaves, plants, and grizzly bear bones all showed high levels of nutrients coming from the ocean. Twenty-two different types of animals were observed eating salmon carcasses on Washington's Olympic Peninsula. Jeff Cederholm, a fisheries scientist with the Washington Department of Natural Resources, said that salmon "are a keystone species. All the other wildlife or plant communities have, in some way, some dependency." Young salmon are particularly dependent on the food provided by the carcasses of their elders. Because streams in the Northwest are generally low in nutrients, salmon appear to have evolved to return to their birthplace, providing nutrients to the next generation. The extra food allows the young salmon to grow stronger before their ocean migration, which in turn increases the chance of the fish returning back to the river (Jeff Barnard, "Salmon Recycle Nutrients," AP, 1/5/2000 Watershed Currents - 4(1) March 31/2000 watershed_currents@iatp.org).

Eutrophication (normally caused by pollution) is expected to worsen in 70% of the world's coastal areas over the next two decades (01E2).

In Asia, the cumulative weight of the fish living in its coastal waters (biomass) is estimated to be 8-12% of what it was half a century ago (04V1).

Top 10 Pollutants in (US) Estuaries (from a chart) (EPA Journal, Sept.-Oct.1990)

Percentage of US Shellfish beds in which Harvesting is Banned or Limited because of Pollution (91S1), (80M1)
Year - |1966|1971|1974|1980|1985|1990
Percent| 21 | 27 | 28 | 25 | 31 | 37

(US Generally) The National Estuary Program (US) was established in 1987 to direct greater federal attention to these important waters and to develop actions to restore the ecological integrity to these areas. Today, 28 nationally significant estuaries are part of the program. 17 of these have completed and secured EPA approval of their comprehensive estuary plans. (Ted Morton, American Oceans Campaign, 9/10/97, Ted.Morton@radagast.wizard.net).

(US Generally) About 40,000 acres of US coastal wetlands that provide habitats for 75% of US commercial fish catches are disappearing each year ("US: Oceans' Woes Growing Deeper" Seattle Times (9/2002)).

(Gulf of Mexico) The dead zone in the Gulf is as large as it has ever been, at least 8,006 square miles, stretching from the Mississippi River mouth to an area west of Sabine Pass in Texas (01U2).

(Gulf of Mexico) In 2000, a national task force drafting a plan to decrease the size of the "dead zone" in the Gulf of Mexico asked agricultural officials in the Midwest to help reduce by 30% the amount of nitrates flowing into the Mississippi River and its tributaries. The excess nitrogen that the Mississippi River empties into the Gulf causes algae to flourish. When that alga dies and decomposes, the decomposition depletes oxygen in the water and makes it impossible for other organisms to survive. Heavy use of fertilizer is believed to account for 65% of the nitrates that flow into the water. Because of that, the task force was preparing in 2000 to ask states in the Mississippi River basin to try to make the 30% reduction in the amount of nitrogen that ends up in the water (01U2).

(Louisiana) Louisiana loses 25-35 square miles of coastal wetlands each year. Those wetlands also act as a nursery for the nation's largest fisheries in the continental US (02D3).

Nowadays, less than 15% of the European coastline is considered in 'good' condition (07A1). Comments: This probably pertains to the condition of the fishery off-shore from the indicated point on the coastline.

Many European coastal habitats have been lost or severely degraded. It is estimated that less than 15% of the European coastline is in 'good' condition (99E1) (07A1).

In the Wadden Sea region (of the Netherlands), about 15,000 km² of wetland, lagoons, coastal lakes and tidal flats have been embanked, drained and converted into arable land and pasture over the centuries (Figure 4 in Ref. (07A1); see also (92W2) and (97W2)). In the United Kingdom land reclamation (development) has affected at least 85% of the estuaries since Roman times, with losses of inter-tidal areas ranging between 25 and up to more than 80% (91D1); such widespread claim of estuarine land is continuing at rates of 0.2-0.7%/ year (07A1)

In Italy, a survey carried out by World Wildlife Fund (WWF) showed that, in 1996, 42.6% of the entire Italian coast was subject to intensive human occupation (areas completely occupied by built-up centers and infrastructures), 13% of Italy's coast had extensive occupation (free zones occupied only by extensive building and infrastructures) and only 29% was free from buildings and infrastructures (99E2) (07A1).

It is estimated that, in the Baltic Sea and North Sea regions, nitrogen (N) and phosphorus (P) loads from land and atmosphere have increased by about a factor of 2-4 and 4-8, respectively, since the 1940s (92N1), (01E3), (02K1) (07A1).

In the north Adriatic Sea nutrient load has been increasing since at least 1900 and it markedly intensified after 1930 (95B3), (04S1), with a doubling of nutrient loads in the Po River between 1968 and 1980 (Marchetti et al. 1989). In the Black Sea, concentrations of nitrate have increased by a factor of 5 and phosphate by a factor of 20 from the 1960s to the 1980s (92G1) (07A1).

Despite its relatively small geographic size, Europe has a very long coastline, approximating 325,892 km, including islands (00P2). It comprises the main marine regions of the northeast Atlantic, part of the Arctic, the Baltic Sea, the North Sea, the Mediterranean Sea and the Black Sea (03F1), (06E2). It includes primarily temperate environments as well as some Arctic and subtropical climate environments and covers a variety of geo-morphological features (02E1) (07A1).

According to a 2004 inventory, the total cover of marine/ coastal wetlands in Europe is around 51,910 km² (04N2) (07A1).

Some estimates suggest that temperate estuaries and coastal areas of Europe may have lost approximately 67% of the wetlands that once existed (06L1) (07A1). (su5) Recent estimates have also suggested that approximately two thirds of all European coastal wetlands that existed at the beginning of the 20^th century have been lost (06E2) (07A1).

Denmark, the Netherlands, Germany, Finland, Lithuania, the United Kingdom, Spain, Greece, Italy, France, Poland, Romania and parts of Portugal and Sweden have reported losses of wetland exceeding 50% of original area, with peaks above 80% for some regions (Table 2 of Ref. (07A1).

It has been suggested that, in the Mediterranean Sea, 28,000 km² (more than 90%) of coastal wetlands have been lost since Roman times (01U5). (su5)

In the United Kingdom, an estimated 913 km² of estuary area and 550 km² of salt marshes have been claimed since Roman times for agricultural, urban, harbor and industrial developments (91D1), (04N2) (07A1).

In England and Wales, it is estimated that 15% of salt marshes were lost between the 1940s and the 1970s (04N2) (07A1).

About 15,000 km² of coastal wetlands have been lost during this long history of progressive embankments (05R1) and the whole Wadden Sea (part of the Netherlands) has been reduced to nearly half of its primordial size (07A1). (Embankments apparently mean dikes.)

It is estimated that there were about 7000 km² of coastal marshes remaining in Italy at the end of the 19^th century, no more than 1920 km² in 1972, and less than 1000 km² today (95S1) (07A1).

In the Po (River) delta, 98% of the freshwater marshes and more than 70% of the salt marsh that existed at the beginning of the twentieth century have been claimed (Figure 8 of Ref. (07A1)). The ancient Po delta (until the twelfth century A.D.) covered about 1300 km², while the modern Po delta covers 730 km² (07A1).

Between 1990 and 2000 there has been a total net loss of 390 km² of coastal wetlands around European coastlines, a significant proportion of which was lost as a result of drainage to reclaim land for development and afforestation (06E2) (07A1).

In the United Kingdom it is estimated that at least 88% of estuaries have lost inter-tidal habitats, and about 25% of overall estuarine inter-tidal flats have been removed with peaks of up to 80% in some estuaries such as the Tees (99U4), (05O2).

On the Dutch continental shelf, fisheries are now so intensive harvested that every square meter is trawled, on average, once to twice a year (95L1). This broadly applies to the entire North Sea seabed (97G2) (07A1).

Europe's coastline length (including islands) is 325,892 km (00P2)

Europe's present coastal wetlands cover 51,910 km². More than 65% of Europe's coastal wetlands area that existed around 1900 has been lost (04N2), (06E2). (su5)

Europe's present sea grasses cover 7290 km². Historical losses* of Europe's seagrass areas exceed 65% (02D6), (03G1). (su5)

In Italy, around 7000 km² of coastal marshes were present at the beginning of the 1900s, no more than 1920 km² in 1972 and fewer than 1000 km² today (95S1) (07A1).

Losses of coastal wetlands and sea grass meadows exceeding 50% of their original area have been documented for most European countries where long-term data were available (07A1). Peak losses of coastal wetlands and sea grasses exceed 80% in many of Europe's coastal regions (07A1). (su5)

About 20% of the EU coastline is retreating by 0.5 to 2.0 meter/ year, with some retreating 15 meters/ year according to a European Commission study of 2004. Some 55% of Poland's beaches are eroding, 37.8% of Cyprus beaches are eroding. Some 28.6% of Greece's beaches are eroding. Some 25.5% of Belgium's beaches are eroding. Some 23% of Italy's beaches are eroding (Ed Ayres, "Erosion Eating Away Europe's Coast", World Watch (September-Oct. 2004, p.8.).

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SECTION (7-D) ~ Sargassum and Seagrass ~ [D1]~General, [D2]~Management, [D3]~Human Uses, [D4]~Role in Marine Ecosystems

Some 58% of the world's seagrass meadows (composed of submerged flowering plants) are currently declining. The rate of loss was less than 1%/year before 1940. Since 1990 the rate of loss has been 7%/ year. This is based on more than 215 studies and 1800 observations dating back to 1879. The rate of loss of sea-grasses is similar to that of coral reefs and tropical rainforests. Sea-grasses have been disappearing at the rate of 110 km²/ year since 1980. The two primary causes are direct impacts from coastal development and dredging activities, and indirect impact of declining water quality (09U1). (Some 45% of the world's population lives on the 5% of the land adjacent to the coast.)

Fish and shellfish rely on sea-grasses for nursery habitat. Sea-grasses export energy in the form of biomass and animals to other ecosystems including marshes and coral reefs. Sea-grasses provide critical habitat for aquatic life, alter water flow, and can help mitigate the impact of nutrient and sediment pollution (09U1).

World aquatic plant production in 2004 reached 13.9 million tonnes (US$6.8 billion). About 10.7 million tonnes of aquatic plants came from China; 1.2 million tonnes came from the Philippines; 0.55 million tonnes came from Republic of Korea, and 0.48 million tonnes came from Japan (07F1).

Seagrasses (rhizomatous, clonal, marine plants) form some of the most valuable and productive coastal ecosystems in the biosphere (97C2). They provide food and habitat for a variety of biota and play a fundamental role in carbon- and nutrient-cycling, water quality control, and sediment dynamics (02D6) (07A1) (su5).

The World Atlas of Sea grasses (03G1) provides the most current and comprehensive compilation of information, documenting some 177,000 km² of seagrass habitat. The World Atlas of Sea grasses (03G1) suggests a tentative global seagrass area of 500,000 km² (07A1). (su5)

The World Atlas of Sea grasses (03G1) documents a coverage of sea grasses of 1850 km² in Scandinavia and the Baltic Sea, 338 km² in western Europe (United Kingdom, Wadden Sea (Netherlands), Portugal and Atlantic France and Spain), 4152 km² in western Mediterranean countries (Italy, France and Spain), and 950 km² in the northwest Black Sea (Figure 9). It has been conjectured that sea-grasses in the Mediterranean cover 25,000 to 45,000 km² (98P3) (07A1).

Awareness of the severe degradation of sea grass meadows is increasing (e.g., see, among others, the reviews in Refs. (96S1), (00H3), and (02D6)). Reports consistently identify a long-term trend of worldwide seagrass decline, about 70% of which can be probably attributed to direct human-induced disturbance (96S1). Less information is available concerning the degradation caused by indirect impacts (02D6). It has been estimated that a global loss of 12,000 km² of sea grass meadows occurred during the 1990s alone (96S1), about 7% of the world's known sea-grass area (03G1) (07A1). (su5)

Denmark records of eelgrass distribution date back to 1900 (03B2). In 1900 Denmark's eelgrass covered about 6726 km² (Figure 10 of Ref. (07A1)); by 1940, 93% of the distribution of eel-grass areas was lost (07A1).

For the French mainland coast, sea grass habitat loss is estimated as 10-15%. This would increase up to 30-40% if the decline in shoot-density is also taken into account (07A1).

There have been clear losses of sea grasses on the Italian coast of the north Adriatic Sea. Geological data have shown that sea grass beds there were probably common before the 1800s and experienced dramatic regressions to virtual extinction in the last two centuries (95B3), (95C1), (97R1) (07A1).

Severe seagrass loss is still in progress in Europe, as is evident along 200 km of the Skagerrak Swedish coast (03B3). Here, 50 of 69 mapped meadows of Zostera marina have shown average declines of 58% between the 1980s and 2000, corresponding to a lost surface of about 10.61 km² (07A1).

International concern about the conservation of sea-grass beds has led to the banning of trawling on sea-grasses in European Community waters (04T1) (07A1).

Most Mediterranean native oyster beds are in such poor conditions that they are unable to support intensive culture (01B4) (07A1). (su5)

In the 18^th and 19^th centuries, large offshore oyster grounds in the southern portion of the North Sea and the English Channel produced up to 100 times more than today's 100-200 tonnes (99U4), (05B2) (07A1). (su5)

The main factors that probably threaten native oyster reefs nowadays include illegal fishing, by-catch in trawling targeting other species, poor water quality, pollution, changes to the environment (e.g., habitat loss due to coastal development) and the introduction of non-native competitors, predators and diseases (03J1), (05O2) (07A1).

The total output of the world's seaweed industry amounts to around US$6 billion. More than 8 million tonnes of wet seaweed used annually. Seaweeds are widely used as food but are also an important ingredient for the cosmetics industry. They also serve to produce hydrocolloids (alginate, agar and carrageenan), which are used as thickening and gelling agents. This document highlights the rising importance of seaweed farming and shows how an essential Asian food has become popular in North and South America as well as in Europe. The report will be useful to those who wish to know more about the seaweed industry, about the markets for commercial seaweeds and about the various sources and methods of production. It is written with a minimum of technical language and is designed to assist in making decisions concerning seaweeds and the seaweed industry (Dennis J. McHugh, "A guide to the seaweed industry," http://www.fao.org/DOCREP/006/Y4765E/Y4765E00.HTM, FAO Fisheries Technical Papers, 2003.).

Worldwide loss of sea-grass because of pollution could result in "underwater prairies turning into marine deserts." Among species most affected: prawns and lobsters. Especially hard-hit are the nearly 20,000 square miles of Australian seagrass beds that contain "half the world's estimated 70 species" of sea grasses (Reuters (3/27/00)). Comments: Seagrass beds are prime breeding grounds for many fisheries. (su5)

(Sea grass) Worldwide loss of sea grass because of pollution could result in "underwater prairies turning into marine deserts". Among species most affected: prawns and lobsters. Especially hard-hit are the 20,000 square miles of Australian sea grass beds that contain "half the world's estimated 70 species" of sea grasses (Reuters (3/27/00)).

(Sea grass) Underwater grasses a key habitat component and indicator of ecological health, reversed recent declines and increased by 7% in Chesapeake Bay. The growth, however, was limited to the mid bay, up 22%, as "acreage declined in the upper and lower bay, down 9%. Total underwater grass acreage increased to 68,125 acres still well below the 600,000 acres that protected shoreline and provided food and shelter for many species around 1900. Much of the grasses were destroyed in the 1960s and 70s when silt from development choked it, while pollution produced algae blooms blocked sunlight vital to the grasses (AP 6/15/00, GREENLines, 6/27/00, Issue #1158, The Endangered Species Coalition).

Underwater grasses a key habitat component and indicator of ecological health, reversed recent declines and increased by 7% in the Chesapeake Bay says (AP 6/15/00). The growth, however, was limited to the mid bay, up 22%, as "acreage declined in the upper and lower bay, down 9%. Total underwater grass acreage increased to 68,125 acres still well below the 600,000 acres that protected shoreline and provided food and shelter for many species around the turn of the century. Much of the grasses were destroyed in the 1960s and 70s when silt from development choked it, while pollution produced algae blooms blocked sunlight vital to the grasses. (GREENLines, Issue #1158 The Endangered Species Coalition (6/27/00))

Over 75% of China's 50,000 km of major rivers are unable to support fish (Johns Hopkins University School of Public Health report "Water Crisis Looms as World Population Grows" (8/26/98)). Comments: This refers to the levels of pollution.

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