Grantee Research Project Results
Tracing the Fate of Nitrogen Inputs from Watersheds to Estuaries
EPA Grant Number: R824767Title: Tracing the Fate of Nitrogen Inputs from Watersheds to Estuaries
Investigators: Deegan, Linda A. , Peterson, Bruce J.
Institution: Marine Biological Laboratory
EPA Project Officer: Packard, Benjamin H
Project Period: January 1, 1996 through December 1, 1997
Project Amount: $232,323
RFA: Water and Watersheds (1995) RFA Text | Recipients Lists
Research Category: Watersheds , Water
Description:
The objective of this project is to determine experimentally the fate of watershed-derived nitrogen and organic matter in the interface where rivers first encounter tidal waters: the oligohaline zone. In this region, river-borne dissolved and particulate nitrogen undergoes major transformation, including uptake by planktonic and benthonic algae, freshwater marshes and macrophytes, and conversion by bacteria and consumers. The dynamic oligohaline production cycle supports high consumer biomass and growth rates, and nourishes a vital and productive faunal habitat that is a nursery for fish species important to commerce and recreation. Transformations of watershed-derived nutrients and organic matter in the oligohaline zone are currently modeled superficially because they are difficult to quantify at the ecosystem scale.The importance of nutrients and organic matter from the watershed to the oligohaline food web will be examined experimentally by adding 15N-enriched nitrate to the oligohaline reach of the Parker River (MA), the site of an ongoing Land Margin Ecosystem Research (LMER) program. By adding the tracer to this critical estuarine zone, questions about the transformations of materials from watersheds as they enter tidal waters, and about the influences of changing land use on important fauna of coastal waters, can be answered simultaneously.
The experiment will provide information to test complex food web models that are otherwise very difficult to confirm.
Publications and Presentations:
Publications have been submitted on this project: View all 8 publications for this projectJournal Articles:
Journal Articles have been submitted on this project: View all 2 journal articles for this projectSupplemental Keywords:
water, watershed, estuary, nitrogen oxide, aquatic, ecology, biology, hydrology, modeling, northeast, Atlantic coast, Massachusetts, MA, Region 1., RFA, Scientific Discipline, Geographic Area, Water, EPA Region, State, Chemistry, Ecology, Biology, Watersheds, Hydrology, Nutrients, Water & Watershed, water quality, bioassessment, nitrogen inputs, Land Margin Ecosystem Research, nitrogen oxide, aquatic biota, fate and transport, oligohaline zone, Region 1 , aquatic ecosystems, nutrient supply, river ecosystems, bacteria, fishProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.