Ongoing Drivers of Wetlands Depletion

摘要

Private land-use decisions can be affected dramatically by public investments in highways, waterways, flood control, or other infrastructure. The large movement of jobs from central cities to suburbs in the postwar United States and the destruction of Amazon rain forests have occurred with major public investment in supporting infrastructure. Private land-use decisions can generate major environmental and social externalities - or, in common language, unintended consequences.rnIn an analysis that appeared in 1990 in the American Economic Beview, Adam Jaffe of Brandies University and I demonstrated that the depletion of forested wetlands in the Mississippi Valley - an important environmental problem and a North American precursor to the loss of South American rain forests - was exacerbated by federal water-project investments, despite explicit federal policy to protect wedands. That analysis is as germane today as it was when it first appeared.rnForested wedands are among the worlds most productive ecosystems, providing improved water quality, erosion control, floodwater storage, timber, wildlife habitat, and recreational opportunities. Their depletion is a serious problem.