WATER RESOURCES RESEARCH GRANT PROPOSAL
Project ID: 2003NJ47B
Title: Potential Nitrogen Saturation in Urban Wetlands
Project Type: Research
Focus Categories: Nitrate Contamination, Wetlands, Ecology
Keywords: nitrogen saturation, nitrate,wetlands, nitrification, denitrification, urban wetlands, depressional wetlands, riverine wetlands
Start Date: 03/01/2003
End Date: 03/01/2004
Federal Funds: $1990.00
Matching Funds: $12807.00
Congressional District: 6
Principal Investigators: Stander, Emilie; Joan G. Ehrenfeld
Abstract: It is a widely
held belief that wetland systems do not experience nitrogen (N) saturation
owing to their ability to remove nitrate (NO3-) through denitrification.
due to hydrological alteration resulting from urban land use, urban wetlands
in northeastern New Jersey may experience lowered water tables and thus overall
drier conditions and wet-dry cycles that may reduce NO3- removal capacity.
This may cause New Jersey’s urban wetlands to be acting as sources
rather than sinks of NO3-, leading to elevated NO3- concentrations in receiving
bodies and associated impacts on the integrity of aquatic ecosystems in this
state. The proposed research will investigate the occurrence of N saturation
symptoms in urban wetlands located in northeastern New Jersey and therefore
directly addresses research priorities one, the integrity of aquatic and
systems, and five, the impacts of land-use practice and change on water resources,
of the RFP. The proposed research can also serve to direct restoration and
management guidelines in the state. If it is demonstrated that lowered water
tables, dry soils, and wet-dry cycles are responsible for degradation of
function, streambank and riparian buffer restoration projects can focus on
restoring saturated hydrological conditions to these systems.
Objectives of the Study include:
1. To document net N mineralization, nitrification, denitrification, and N loss to shallow groundwater under wet and dry conditions in urban wetlands of contrasting soil types over the course of a one year field-based study.
2. To determine whether urban wetlands with organic and mineral soils are displaying symptoms of N saturation. For the purposes of this study, symptoms of N saturation are considered to be elevated NO3- concentrations in soil water collected during dry and saturated conditions as well as during the initial flush after a rainstorm.
A survey will be conducted for the presence or absence of N saturation in six urban wetlands adjacent to streams in northeastern New Jersey, representing the two main wetland soil types in this part of the state. The six sites will consist of three depressional wetlands with organic soils and three riverine wetlands with mineral soils.
Progress/Completion Report PDF