Quote:
Originally Posted by altyfc
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A doubling of atmospheric CO
2 is something to be concerned about.
Science Daily has the same story with this Background information:
* Wetlands along the flood-prone Mississippi once stored 60 days of the river's floodwater; today they can store only 12 days' worth.
* Around Africa's Lake Victoria, wetlands are so degraded they can no longer filter nitrate and phosphate runoff from surrounding land. The result: eutrophication and an explosive growth of lake-clogging water hyacinth.
* In Malaysia, 90 percent of freshwater swamps have been drained for rice cultivation.
* A study of a large wetland in arid northern Nigeria found it yielded an economic benefit in fish, firewood, cattle grazing lands and natural crop irrigation 30 times greater than the yield of water being diverted from the wetland into a costly irrigation project.
* At US$15 000 per hectare per year, the economic value of flood prevention and other ecological services provided by wetlands is greater than any other ecosystem -- seven times that of the next most valuable, tropical rainforests, according to a recent study.
* The peat bogs of Siberia, North America and Scandinavia contain a third of all carbon in the world's soils. Those in Scotland contain more than 90 percent of the carbon in British soils and forests.
* The US will spend $700 million over two decades to revive the Florida Everglades. It will include six artificial wetlands ("storm water treatment areas"), to receive and cleanse excess nutrients from neighbouring farm districts.
* The world's most threatened wetlands include those around the Mediterranean, where for two millennia the population has been draining wetlands and floodplains for agriculture -- and more recently for urban areas, tourist developments, and to eradicate malarial mosquitoes.
* Both Spain and Greece drained 60 percent of their wetlands in the last century. Pumping of groundwater for agricultural irrigation is drying Spanish wetlands such as the Doņana reserve, one of Europe's top sanctuaries for wintering birds, where the water table is falling one meter every two years.
* Wetlands constitute an estimated 20% of South America but they are poorly mapped or classified by characteristics.
* The vast, remote and relatively pristine Pantanal, spanning 160,000 square km, is confronted by increasing development pressure. Its catchment area straddles Brazil, Bolivia and Paraguay, while Uruguay and Argentina are downstream.
A carbon "bomb"?
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