CLIMATE CHANGE: Wetlands Loss Fuelling CO2 Feedback Loop
By Stephen Leahy
Uxbridge, CANADA, Jul 21 (IPS) - Wetlands are dangerous, scientists say, in the sense that they are ticking carbon bombs best left alone. To help stave off extreme climate change, existing wetlands should be enhanced and new wetlands created so they could capture more carbon.
"Wetlands hold massive stores of carbon -- about 20 percent of all terrestrial carbon stocks," said Eugene Turner, a leading wetlands expert at Louisiana State University's Coastal Ecology Institute.
However, wetlands, including peatlands, continue to be converted to other uses around the world, resulting in large emissions of carbon and methane, a potent greenhouse gas that has 21 times the warming impact of carbon dioxide.
By itself, climate change is already degrading wetlands, especially in the Arctic and near Arctic regions where the once permanently frozen peatlands are thawing, Turner told IPS prior to the opening of the Eighth INTECOL International Wetlands Conference in Cuiaba, Brazil on Monday.
"Researchers have been measuring huge releases of carbon and methane up there," he said. "It's crazy to add to that by draining or mismanaging other wetlands."
While birds and bird lovers value wetlands, hardly anyone else does. Besides capturing and holding carbon, wetlands are hotspots of biodiversity, crucial components in flood control and in providing clean water. The recent disastrous floods in the U.S. Midwest would have been far less damaging if wetlands in the region hadn't been drained decades ago, Turner said.
"Humanity in many parts of the world needs a wake-up call to fully appreciate the vital environmental, social and economic services wetlands provide," said conference co-chair Paulo Teixeira, coordinator of the Cuiaba-based Pantanal Regional Environmental Programme, a joint effort of the United Nations University (UNU) and Brazil's Federal University of Mato Grasso (UFMT).
"The benefits of wetlands are not understood by the public. We hope to change this through our meeting," Teixeria said in an interview.
The INTECOL conference will assess the status of global wetlands, identify knowledge gaps, foster greater collaboration and consistency in wetland science worldwide, and offer plain-spoken policy prescriptions for decision makers with an appeal to adopt them with urgency, he said.
Climate change has dramatically increased the need to protect wetlands. Without substantial reductions in emissions of fossil fuels, up to 85 percent of wetlands will be lost in the future. That loss is far more than a loss of important bird habitat -- it would also release enough carbon and methane to almost certainly tip the climate into an era of extreme and rapid change, experts believe.
"Too often in the past, people have unwittingly considered wetlands to be problems in need of a solution," said U.N. Under Secretary-General Konrad Osterwalder, rector of UNU.
"Yet wetlands are essential to the planet's health -- and with hindsight, the problems in reality have turned out to be the draining of wetlands and other 'solutions' we humans devised," Osterwalder said in a statement.
Covering just six percent of Earth's land surface, wetlands -- including marshes, peat bogs, swamps, river deltas, mangroves, tundra, lagoons and river floodplains -- contain an estimated 771 gigatonnes (771 billion tonnes) of greenhouse gases, both CO2 and more potent methane, an amount in CO2 equivalent comparable to the carbon content of today's entire atmosphere.
Some 60 percent of wetlands worldwide -- and up to 90 percent in Europe -- have been destroyed in the past 100 years, principally due to drainage for agriculture but also through pollution, dams, canals, groundwater pumping, urban development and peat extraction.
Cuiaba, the location of the conference, is next to South America's giant Pantanal wetland covering 165,000 square kilometres -- an area roughly equal to Florida -- in Brazil, Bolivia and Paraguay. Considered one of the world's most bio-diverse ecosystems, the Pantanal is a complex patchwork of lakes, lagoons, rivers, forest and forest islands. Many of the thousands of species found there are at risk of extinction. It is also the wintering grounds for a large number of migratory birds that summer in North America.
While under pressure from intensive agricultural, industrial and urban development, the Pantanal is holding up "pretty well" in part because local and state governments understand its value as a tourist attraction, Teixeria said. The future challenge is to manage the social and economic dimensions and, since wetlands don't recognise political boundaries, developing management agreements with Bolivia and Paraguay, which share the wetland.
The most immediate challenge to wetlands around the world is competition for water and land in an increasingly hungry world. Teixeria and Turner agree that better management can reduce those pressures while preserving the important ecological services wetlands provide. One service that needs far more recognition is the ability of wetlands to help stabilise the climate, Teixeria pointed out.
Preserving healthy wetlands is a far better alternative than trying to fix or re-create them, said Turner, noting that the U.S. is spending six to seven billion dollars to try to restore Florida's Everglades wetlands.
"Wetlands can be restored, but most attempts are failing. It's not easy and it takes many years, decades even to bring them back," he said.
Global climate change is the biggest future threat to wetlands. If global average temperatures rise 3 or 4 degrees C, then the Pantanal, like most wetlands, will likely dry out. That would also release quantities of carbon and methane, putting the climate on a runaway train. Thus far, burning fossil fuels has raised global temperatures 0.8 degrees C on average but the increases have been several times greater in the Arctic.
Wetlands can play an important role in stabilising the climate. "Our future is tied to the health of wetlands," said Turner.
(END/2008)
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