SS3.06 Large Scale Change in Prominent Ecosystems
Date: Wednesday, June 12, 2002
Time: 4:15:00 PM
Location: Lecture Theatre
MagnienRE, Maryland Dept. of Natural Resources, Annapolis, USA,
Phillips, S, W, U. S. Geological Survey, Baltimore, USA,
Since 1977 the Chesapeake Bay region has been struggling to reduce the impacts of eutrophication in the nation’s largest estuary. Despite this long-term commitment, only modest progress has been observed in water and habitat quality. Nutrient loadings basin-wide have not changed greatly although there are clear geographical and source-based patterns. Progress has been greatest at wastewater treatment plants (WWTPs) where N and P loads have been reduced by 27 and 53%, respectively, but these gains are threatened as wastewater flows increase. Estuarine tributaries receiving a large proportion of their nutrient loads from WWTPs have experienced modest improvements in water and habitat quality. While many well-intended actions have been implemented for nonpoint sources, the lack of substantial reductions in nutrient application to the land surface and lag times due to watershed processes have resulted in little, if any, reductions from these sources, especially for nitrogen. Given future projections of population increases, unprecedented initiatives to reduce nutrient loads, as well as aggressive measures to improve habitats within the Bay, will undoubtedly be needed to reach desired living resource goals.