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Wetland Threats and Loss
Status and Trends of Wetlands in the Conterminous United States: 1986
(as reported in the as
National Wetlands Inventory summary by the same name in 2000)
The current status of wetlands is constantly changing. Since the
wetland management plans of the 1980s, wetland restoration appears to
be on the rise. Still, despite efforts to conserve the land, hundreds
of thousands of wetland acres are being drained each year.
In accordance with the Emergency Wetlands Resources Act of 1986, the
Fish and Wildlife Service conducts status and trend studies of the nation's
wetlands, and reports the findings to Congress each decade. The following
are the results from the third and most recent national wetlands report:
Notes about the study: A comprehensive inventory of all the U.S.
wetlands would have been prohibitively expensive, so national wetland coverage
was estimated using a sampling approach that involved 4,000
plots, each four square miles in area. Each plot was interpreted with aerial
imagery that was compared to imagery of the previous decade. The differences
between the data were analyzed and the changes statistically estimated.
The aerial imagery recognized only the losses and gains of wetlands acres,
not the quality of those wetlands.
- The estimated wetlands loss from 1986 to 1997 was 58,000 acres annually,
marking an 80% reduction from the previous decade. Between 1986
and 1997, a net of 664,000 wetland acres was lost.
- National wetland losses were attributed to: Urban Development (30%),
Agriculture (26%), Silviculture (23%), and Rural Development (21%).
- Although the U.S. has not met the goal of no
net loss of wetlands, "substantial progress has been made in reducing
the rate of loss."
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