Monitoring the ecological condition of estuaries in the United States∗

Publisher Website
Google Scholar
Abstract
The purpose of the Environmental Monitoring and Assessment Program/ Estuaries component (EMAP‐E) is to determine the current status, extent, changes, and trends in ecological indicators of the condition of the nation's estuarine resources on a regional and national basis. Monitoring activities in the Virginian (Mid‐Atlantic) and Louisianian (Gulf of Mexico) Provinces focus on measurements describing the benthic community, the fish community, water quality, levels of sediment and tissue contamination, sediment toxicity, wetlands extent/condition, and seagrasses extent/condition. Estuarine monitoring is based on an EMAP‐E probability‐based sampling design conducted over a 60‐day period during July‐September of each year. Monitoring activities in the Virginian Province began in 1990 and have continued annually while monitoring in the Louisianian Province was initiated in 1991. The results of 1990 monitoring in the Virginian Province show that 20% of the sediments of the Mid‐Atlantic region suffered from poor biological conditions while 15% of the area showed undesirable conditions in relation to poor water clarity and the presence of marine debris. In 1991, 31% of Gulf of Mexico estuarine sediments in the Louisianian Province displayed poor biological conditions, as measured by benthic community structure, and 32% of the area was characterized by poor water clarity, the presence of marine debris, and elevated levels of fish tissue contaminants. Efforts are presently underway to begin to assess degradation “causes” using statistical associations among exposure and stressor data for degraded areas in the two provinces. Monitoring will continue in these provinces, as well as be initiated in the Great Lakes, in 1992 and monitoring in other areas of the country (Carolinian Province, Southeast) is scheduled to begin in 1994.