Studying sources and sinks of nutrients and bio-reactive elements, as well as monitoring variations in the CO2-system parameters (pH, pCO2, DO, DIC), provides contextual information needed for ecosystem modeling and an understanding of the response of the estuarine and adjoining reef to forcing from the upper watershed. To achieve the above, it is critical to understand the spatial inputs of macronutrients (P, N and Si) and pre-formed organic matter into the watershed, and to establish the temporal variations of the fluxes of these materials under varying conditions of precipitation and hydraulic forcing of groundwater, as well as to measure the estuarine and coastal responses to these inputs. Quantifying sources of selected bioactive trace elements and pollutants within the watershed, and developing an understanding of the processes that modulate their fluxes to the coast, are also important to quantifying coastal productivity.