Title: Restoring Biogeochemical Functions in Degraded Urban Stream Ecosystems
Project Type: Research
Start Date: 03/01/2006
End Date: 02/28/2007
Congressional District: 4
Focus Categories: Nutrients, Water Quality, Ecology
Keywords: biogeochemistry, denitrification, hydrologic connectivity nitrogen, organic matter, restoration, urban streams
Principal Investigator: Bernhardt, Emily S.
Federal Funds: $ 25,619
Non-Federal Matching Funds: $ 51,237
Abstract: Understanding the role stream ecosystems play in watershed nutrient retention is a critical frontier in biogeochemistry. A growing body of research demonstrates the important effect stream ecosystems have in altering the form, timing and magnitude of watershed nitrogen (N) losses. Yet most of this research has been conducted in minimally impacted watersheds. In the most extreme sense, streams in heavily urbanized watersheds may be functionally disconnected from upland soils, with a high proportion of streamwater routed over pavements and through storm drains directly into channels. These streams, in turn, will become little more than gutters routing stormwaters towards the sea. Urban streams thus represent the worst case scenario, integrating a large number of simultaneous watershed insults. Several very recent studies suggest that these streams have very reduced capacities to transform and retain N. These same studies also demonstrate that N transformation and retention is closely tied to organic matter (OM) dynamics. Research proposed here will document the effects of urbanization on stream N and OM cycling. The proposal outlines a research program that will: 1) document differences in N and OM processing between urban and minimally impacted watershed streams; 2) evaluate the effectiveness of channel reconfiguration restoration efforts in restoring N and OM dynamics to urban streams; and 3) experimentally test the effect of OM supplements on stream N dynamics. The research program has been planned in collaboration with the NC Ecosystem Enhancement Program's Monitoring and Research Team and will be conducted as a joint effort between members of Bernhardt's lab and staff of the NC EEP.
Progress/Completion Report, PDF