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Wetlands vanishing at triple rate of forests

The world has lost about 35% of its swamps, bogs and other wetlands since nearly a half-century ago, sped up by climate change and overpopulation.

GENEVA (AN) — The world has lost about 35% of its swamps, bogs and other wetlands since nearly a half-century ago, with the loss rate accelerating because of rising temperatures, populations and urbanization, according to the first assessment by a global treaty among 170 nations.

The Ramsar Convention on Wetlands said the losses between 1970 and 2015 pose a serious threat to the "world's most valuable ecosystem" with a huge amount of biodiversity. Annual rates of loss accelerated from 2000 — and wetlands are now vanishing three times faster than forests.

The findings in the 88-page report are a wake-up call to the essential role that wetlands have in a healthy planet and humanity, said Martha Rojas Urrego, secretary general of the Geneva-based convention, which is ratified by 170 nations.

It aims to protect wetlands and promote their wise use. Wetlands also include coastal areas and river deltas, lakes, rivers, marshes and marine areas such as estuaries, lagoons, mangroves and coral reefs.

Wetlands protect coastlines and other areas from flooding, and they provide food, raw materials and genetic resources for everything from medicines to hydropower. Every part of the planet is affected by their loss. They cover more than 12 million square kilometers, an area bigger than Greenland, and up to 18% of wetlands are listed as protected sites.

"Without them, the global agenda on sustainable development will not be achieved," said Urrego, a biologist and global policy expert from Colombia and France. "We need urgent collective action to reverse trends on wetland loss and degradation, and secure both the future of wetlands and our own at the same time.”

The report said more than 1 billion people depend on wetlands for a living and 40% of the world’s wildlife species live and breed in wetlands, which help regulate climate.

Wetlands also produce 20 to 25 per cent of global methane emissions, and rising temperatures from climate change are expected to increase greenhouse gases from wetlands, particularly in permafrost regions. But peatlands, marshy areas that refer to the peat soil they contain, occupy about 3% of the planet and store twice as much carbon as the world’s forests.

The Ramsar Convention is named for the Iranian city of Ramsar where it was adopted in 1971. The treaty took effect in 1975. Since then 88% of the U.N.'s member nations, representing all the world’s geographic regions, acceded as contracting parties. Every three years, the Conference of the Contracting Parties to the Ramsar Convention on Wetlands meets to set work and budget priorities.

Its first annual report on the global outlook for wetlands was issued ahead of a meeting of the parties to the treaty planned for Dubai, United Arab Emirates in late October.

Waterfowl fly over U.S. wetlands at Chincoteague National Wildlife Refuge (Arete News Photo/USFWS)

Waste and runoff threats

Wetlands are used to grow rice and other food, and to provide freshwater and coastal fish, fresh water, fiber and fuel.

They help regulate climate and hydrological regimes, reduce pollution and disaster risk. And they offer recreation and tourism benefits. Some areas are of great cultural and spiritual importance.

But the most recent water quality trends with wetlands are mostly negative, the report found. Since the 1990s, it said, water pollution has worsened in almost all rivers in Latin America, Africa and Asia. Deterioration is projected to escalate.

"Major threats include untreated wastewater, industrial waste, agricultural runoff, erosion and changes in sediment. By 2050, one-third of the global population will likely be exposed to water with excessive nitrogen and phosphorous, leading to rapid algal growth and decay that can kill fish and other species," the report said.

The assessment found that severe pathogen pollution affects one-third of rivers in Latin America, Africa and Asia, with fecal coliform bacteria increasing over the last two decades.

Salinity has built up in many wetlands, including in groundwater, damaging agriculture, it found. Nitrogen oxides from fossil fuels and ammonia from agriculture cause acid deposition, and acid mine drainage is a major pollutant.

Then there is the threat from too much heat and plastic. "Thermal pollution from power plants and industry decreases oxygen, alters food chains and reduces biodiversity," it said. "At least 5.25 trillion persistent plastic particles are afloat in the world’s oceans and have huge impacts in coastal waters."

In the United States, half of all wetlands already are gone. But developers have been using a system of “wetlands mitigation credits" — wetlands-restoring projects that they pay for as compensation for the wetlands destroyed by their own construction projects. That has become a huge industry in itself, without which the losses would be still greater.

The wetlands mitigation "banks" grew out of the concept of "no net loss" of wetlands set by former U.S. President George H.W. Bush in 1989. There are about 1,500 in use today, helping multinational companies and environmental groups cooperate on wetlands protected by the U.S. Clean Water Act.

Their use — and the wetlands created by them as economic incentives — are under threat now. U.S. President Donald Trump's administration directed the U.S. Environmental Protection Agency to rescind and rewrite a federal rule that protects wetlands and waterways against development.