LINKING WATER QUALITY TO LIVING RESOURCES IN A MID-ATLANTIC LAGOON SYSTEM, USA

摘要: The mid-Atlantic coastal bays are shallow lagoons, separated from the Atlantic Ocean by barrier sand islands with oceanic exchanges restricted to narrow inlets. relatively poor flushing of these lagoon systems makes them susceptible eutrophication resulting anthropogenic nutrient loadings. An intensive water quality and seagrass monitoring program was initiated track ecological changes in Maryland Virginia bays. purpose this study analyze existing data determine status trends any associations between living resources. Analysis revealed several trends: (1) decadal decreases chlorophyll concentrations, followed recently increasing trends; (2) increases coverage, a recent period no change; (3) blooms macroalgae brown tide microalgae; (4) exceedance thresholds: (15 lg/L), total nitrogen (0.65 mg/L or 46 lmol/L), phosphorus (0.037 1.2 dissolved oxygen (5 mg/L) many areas within thresholds were based on habitat requirements for resources (seagrass fish) used calculate index, which compare bay segments. Strong gradients correlated coverage These factors indicate that state transition, suite metrics indicating degrading conditions. Continued intensified management will be required avert exacerbation observed trends. Coastal lagoons worldwide experiencing similar due human pressures, assessing relative biologically relevant can assist determining priorities goals.