Seasonal nitrogen dynamics in Chesapeake Bay: a network approach

摘要: The input, exchange, recycling and export of nitrogen in the mesohaline region Chesapeake Bay have been assessed this study. seasonal rate exchanges between 36 most important components roles these process ecosystem quantified. Results show that demand for by phytoplankton, bacteria benthic algae is highest summer (418 mg N m−2day−1) lowest winter (90 m−2day−1). supply dissolved however, spring (289 m−2day−1), with exogenous ‘new’ during (53 variations suggest loadings continue to sustain high when nutrient appears be short supply. also efflux from sediments overlying water dominates abetted column regeneration, mostly smaller biota (<200 μm). Mesozooplankton, suspension-feeders fish as a whole contribute relatively little on or annual basis total amount regenerated nitrogen. Network analysis dynamics indicates pathways over which recycled are considerably more complicated numerous than those retain carbon system. Finn Cycling Index (FCI) reveals approximates 70% system activity compared 34-46% range other seasons. In contrast, FCI was almost constant 20% all As regards pelagic microbiota, functionated shunt convey excess out system, they comprise very significant retention