National Centers for Coastal Ocean Science (NCCOS) research highlights in the Chesapeake Bay

摘要

The Chesapeake Bay is the largest estuary in theudUnited States. It is a unique and valuable national treasureudbecause of its ecological, recreational, economicudand cultural benefits. The problems facing the Bay areudwell known and extensively documented, and are largelyudrelated to human uses of the watershed and resourcesudwithin the Bay. Over the past several decades as theudorigins of the Chesapeake’s problems became clear, citizensudgroups and Federal, State, and local governmentsudhave entered into agreements and worked together toudrestore the Bay’s productivity and ecological health.udIn May 2010, President Barack Obama signed ExecutiveudOrder number 13508 that tasked a team of Federaludagencies to develop a way forward in the protectionudand restoration of the Chesapeake watershed. Successudof both State and Federal efforts will depend on havingudrelevant, sound information regarding the ecology andudfunction of the system as the basis of management anduddecision making. In response to the executive order, theudNational Oceanic and Atmospheric Administration’sudNational Centers for Coastal Ocean Science (NCCOS)udhas compiled an overview of its research in ChesapeakeudBay watershed.udNCCOS has a long history of Chesapeake Bay research,udinvestigating the causes and consequences of changesudthroughout the watershed’s ecosystems. This documentudpresents a cross section of research results that have advanced the understanding of the structure and functionudof the Chesapeake and enabled the accurate and timelyudprediction of events with the potential to impact bothudhuman communities and ecosystems. There are three main focus areas: changes in land use patterns in the watershed and the related impacts on contaminant and pathogen distribution and concentrations; nutrient inputs and algal bloom events; and habitat use and life history patterns of species in the watershed.udLand use changes in the Chesapeake Bay watershed have dramatically changed how the system functions. Audcomparison of several subsystems within the Bay drainagesudhas shown that water quality is directly related to land use and how the land use affects ecosystem health of the rivers and streams that enter the Chesapeake Bay. Across the Chesapeake as a whole, the rivers that drain developed areas, such as the Potomac and James rivers, tend to have much more highly contaminated sediments than does the mainstem of the Bay itself. In addition to what might be considered traditional contaminants, such as hydrocarbons, new contaminants are appearing in measurable amounts. At fourteen sites studied in the Bay, thirteen different pharmaceuticals were detected. The impact of pharmaceuticals on organisms and the people who eat them is still unknown. The effects of water borne infections on people and marine life are known, however, and the exposure to certain bacteria is a significant health risk. A model is now available that predicts the likelihood of occurrence of a strain of bacteria known as Vibrio vulnificus throughout Bay waters.