ALEXANDRIA, VA - Once considered wastelands, wetlands are now viewed as indispensable transitions between land and water. They filter ground water, recharge aquifers, serve as flood protection from swollen rivers, and provide habitat for countless plant
and animal species. Nearly half the wetlands that existed in the United States when European settlers first arrived have disappeared. As their size and number continue to dwindle, the scientific and environmental community has increased its efforts to s
ave these endangered ecosystems. In the July issue of Geotimes, scientists from a range of disciplines examine efforts to slow the loss of wetlands, and look at the underlying geology of these vital but vanishing re
sources.
Two advocates of holistic management of resources, S. Jeffress Williams and Robert Stewart, describe cooperative research efforts between the U.S. Geological Survey (USGS) and the National Biological Service (NBS). In their article, "Understanding Co
astal Wetland Processes," they describe how the two agencies combine their respective areas of expertise to forecast future coastal conditions, guide coastal-zone management, and direct efforts to mitigate erosion and wetland loss. These cooperative effo
rts are particularly important along the Gulf Coast of Louisiana — an area that contains 40 percent of the nation's wetlands and suffers an annual loss of more than 75 square kilometers per year. As part of a task force formed in 1990, the USGS provides
base topographic maps and information on geologic and sedimentological processes, while the NBS provides time-series habitat maps and studies that trace the dynamics of vegetation and soil processes.
Historically, communities in the tropics lived in symbiosis with wetlands. Wetlands provided water, food for humans and livestock, and building materials. Economic development, the scarcity of productive land, and increased loads of sediment and nutr
ients entering wetland systems have changed that once cohabitable relationship. "Today's political and economic realities make setting aside large tracts of land for inviolate preservation a luxury," explain Thomas Crisman and Lauren and Colin Chapman in
their article, "Conserving Tropical Wetlands Through Sustainable Use." Instead, efforts to protect tropical wetlands must stress multiple use of these systems. By harnessing the natural processes of wetlands for waste-water treatment systems and aquacu
lture, developing communities can preserve wetlands while meeting economic goals.
In his article "Mixing Soil and Water: The Geology of Wetlands," J.L. Richardson, a soil scientist at North Dakota State University, explains the geology of zones where land and water meet. Examination of the soil reveals the wetland's history, locat
ion, and function in the larger landscape. In fact, hydrological characteristics may vary so greatly that analyzing soil morphology and modeling ground-water flow provide the best methods for assessing or delineating wetlands.
Coming in August ... Geotimes looks at the problem of low-level nuclear waste disposal. Three articles examine the politics of selecting disposal sites and review some of the technical considerations and technologies involved in identifying appropria
te locations for these facilities.
Geotimes is published by the American Geological Institute, a nonprofit federation of 29 member societies representing geologists, geophysicists, and other earth and environmental scientists. The Institute also produces GeoRef, an online bibliographi
c database of more than 1.9 million geological references from 1785 to the present.
