Wetlands at risk
Half of the world's wetlands have been destroyed over the last 100 years.
Conversion of swamps, marshes, lakes and floodplains for commercial development, drainage schemes, extraction of minerals and peat, overfishing, tourism, siltation, pesticide discharges from intensive agriculture, toxic pollutants from industrial waste, and the construction of dams and dikes, often in an attempt at flood protection, are major threats to wetlands everywhere.
In the Philippines, a staggering 80% of coastal wetlands have been drained, degraded, or destroyed in just 30 years.
Military action, too, can be a significant factor in wetland decline. Exercises frequently cause immense damage, while wars create the kind of havoc to people and the environment that is being witnessed in the marshes of southern Iraq.
Climate change is also taking its toll.
Global warming is causing polar ice to melt and sea levels to rise. This in turn is leading to shallow wetlands being swamped and some species of mangrove trees being submerged and drowned. Some scientists forecast that climate change will lead to the disappearance of entire island nations.
Yet at the same time, other wetlands - estuaries, floodplains, and marshes - are being destroyed through drought. There is still much to be learned about the impact of climate change on weather patterns.
Another major threat to wetlands is human overexploitation of the underground water table for agriculture, housing, industry, and tourist development.
In all too many places, the amount of water being taken from nature's underground aquifer is far outstripping its ability to replenish itself. The result is that as the water level drops, millions of trees and plants are dying because they are deprived of their life-sustaining supplies.
