BACKGROUND Despite the large stocks of organic nitrogen in soil, nitrogen availability limits plant growth in many terrestrial ecosystems because most plants take up only inorganic nitrogen, not organic nitrogen. Although some vascular plants can assimilate organic nitrogen directly, only recently has organic nitrogen been found to contribute significantly to the nutrient budget of any plant. C...

This paper uses a numerical general equilibrium model to evaluate the welfare impacts of alternative agri-environmental policies in an open economy while recognizing the presence of distortionary agricultural support subsidies and factor income taxes. In this context, the paper indicates that a revenue-neutral budget reform, which cuts all distortionary agricultural support subsidies and pays r...

The Chesapeake Bay plays an important role in transforming riverine nutrients before they are exported to the adjacent continental shelf. Although the mean nitrogen budget of the Chesapeake Bay has been previously estimated from observations, uncertainties associated with interannually varying hydrological conditions remain. In this study, a land-estuarine-ocean biogeochemical modeling system i...

‘Ihe Ipswich River is a low-gradient, coastal river in northeastem Massachusetts. It is about 55 km long and drains an area of 401 km’. Previous observations and studies indicate high levels of dissolved inorganic nitrogen (DIN) in the headwaters of the river due to urban and residential land use (1). However, concentrations drop quickly with distance downstream, presumably due to biological pr...