High-Frequency Concurrent Measurements in Watershed and Impaired Estuary Reveal Coupled DOC and Decoupled Nitrate Dynamics

Rapid changes in land use, pollution inputs, and climate are altering the quantity, timing, form of materials delivered from watersheds to estuaries. To better characterize these alterations simultaneous measurements biogeochemical conditions estuaries over a range times scales needed. We examined strength watershed-estuarine coupling using situ nitrate, terrestrial dissolved organic carbon (DOC), chloride collected 7-month period nitrogen-impaired estuary northeastern US. The watershed exerted strong control concentrations terrestrially derived DOC estuary, attributable relative homogeneity sources forested combined with relatively conservative behavior estuarine waters. Estuarine nitrate patterns were more complex, suggesting influence heterogeneous distribution non-point point high reactivity estuary. Understanding will be advanced through greater use sub-hourly inflows, salinity, water quality their upstream watersheds.