Seasonal hypoxia(dissolved oxygen[DO]levels≤2 mg/l)poses a severe threat to coastal ecosystems globally,including the largest estuary in the United States,the Chesapeake Bay.This V-shaped drowned river valley feature...Seasonal hypoxia(dissolved oxygen[DO]levels≤2 mg/l)poses a severe threat to coastal ecosystems globally,including the largest estuary in the United States,the Chesapeake Bay.This V-shaped drowned river valley features shallow flanks,where the deepest waters experience persistently low DO levels typi-cally initiated during the spring and ending in late summer or early autumn.Reports on low DO conditions in the Chesapeake Bay date back over a century[1].Consistent annual records of summer hypoxic conditions have been available since 1985 based on routine data collected through the Chesapeake Bay long-term water quality monitoring program[2].In 2023,the Chesapeake Bay Program(CBP)reported a record low seasonal hypoxic volume(May to October)of 0.58 cubic miles,accord-ing to the Maryland Department of Natural Resources,and 0.52 cubic miles,as reported by the Virginia Institute of Marine Science.Both volumes are considerably below the long-term average of 0.97 cubic miles(Fig.1).展开更多
基金The research was supported by the U.S.Environmental Protection Agency and the U.S.Geological Survey.
文摘Seasonal hypoxia(dissolved oxygen[DO]levels≤2 mg/l)poses a severe threat to coastal ecosystems globally,including the largest estuary in the United States,the Chesapeake Bay.This V-shaped drowned river valley features shallow flanks,where the deepest waters experience persistently low DO levels typi-cally initiated during the spring and ending in late summer or early autumn.Reports on low DO conditions in the Chesapeake Bay date back over a century[1].Consistent annual records of summer hypoxic conditions have been available since 1985 based on routine data collected through the Chesapeake Bay long-term water quality monitoring program[2].In 2023,the Chesapeake Bay Program(CBP)reported a record low seasonal hypoxic volume(May to October)of 0.58 cubic miles,accord-ing to the Maryland Department of Natural Resources,and 0.52 cubic miles,as reported by the Virginia Institute of Marine Science.Both volumes are considerably below the long-term average of 0.97 cubic miles(Fig.1).
