2000 Progress Report: CISNet for the Neuse River Estuary, NC: A Program for Evaluating Nitrogen Driven Eutrophication Associated with Changing Land Use in a Coastal Watershed

EPA Grant Number: R826938
Title: CISNet for the Neuse River Estuary, NC: A Program for Evaluating Nitrogen Driven Eutrophication Associated with Changing Land Use in a Coastal Watershed
Investigators: Luettich Jr., Richard A. , Paerl, Hans , Pinckney, Jay
Institution: University of North Carolina at Chapel Hill
EPA Project Officer: Hahn, Intaek
Project Period: October 1, 1998 through September 30, 2001
Project Period Covered by this Report: October 1, 1999 through September 30, 2000
Project Amount: $555,300
RFA: Ecological Effects of Environmental Stressors Using Coastal Intensive Sites (1998) RFA Text |  Recipients Lists
Research Category: Environmental Statistics , Water Quality , Ecosystems , Ecological Indicators/Assessment/Restoration


The overall objective of the UNC-CH CISNet project is to build upon the historical water quality data in the Neuse River Estuary (NRE). The components are: (1) bi-weekly monitoring of water quality, (2) determination of atmospheric nitrogen (N) loading, (3) water quality and N loading effects of a large coastal farm, (4) continuous monitoring of circulation, and (5) data management, archival, and integration.

Progress Summary:

Our progress during the past year is described below.

1. Monitoring of Water Quality Parameters Along the Length of the NRE. Following the flooding during fall 1999, salinity was below 5 psu in upstream locations until June 2000. Much of the NRE was stratified and had patches of severe hypoxia throughout the summer and fall 2000. Nitrate concentrations were elevated between October 1999 and March 2000. Overall, concentrations of ammonium and phosphate were high in the summer of 1999, but were reduced in the fall and winter. Late summer 1999, chlorophyll biomass increased but much of the suspended matter was flushed from the NRE following the hurricanes. A large algal bloom occurred between March and June 2000.

2. Enhanced Determination of Atmospheric Deposition of Nitrogen (ADN) to the NRE. There were no statistically significant differences in depositional fluxes of NH4+, NO3-, or DIN among three sites in the NRE basin. Seasonal patterns of N deposition were not driven by precipitation. Direct deposition of N to the estuary surface may be an important source of introduced nitrogen.

3. Water Quality and N Loading Effects From a Large Coastal Farm. Salinity at the mouth of the South River ranged between 10-20 from March to August 1999, but dropped to near zero following the hurricane-related flooding. Chlorophyll a concentrations were low before the storms, but rose to near 30 µg L-1 by the end of 1999. Chlorophyll remained high in the spring of 2000 before declining by summer 2000.

4. Continuous Monitoring of Circulation and Flushing of the NRE. Depending on wind direction, a two-layer flow was generated with flow following the wind in the surface layer and flow opposing wind in the bottom layer. The low frequency response resulted because NE winds pushed water out of the NRE and into Pamlico Sound. The high frequency response suggested that NE winds provided set-up of the water level against the north shore and created a barotropic standing wave. This situation led to wind-driven upwelling and downwelling of water masses in the cross-channel direction.

5. Systematic Management, Archival, and Integration of Data From All Ongoing NRE Research. The data sets include water quality information gathered by our companion groups at the North Carolina Department of Water Quality (NCDWQ) and Weyerhauser, Inc. The integration of IMS data with those of NCDWQ and Weyerhauser provides a weekly snapshot of water quality in the NRE. Data from 1994-1999 are available electronically and on compact disc (CD) from IMS, while the hydrographic data for 2000 can be accessed at the Web site. Included in the CD are specifics of sampling locations, frequencies, and field and laboratory protocols for these three groups monitoring water quality in the NRE.

Future Activities:

Activities to be completed in the next year include:

1. Continue the regular water quality monitoring at each of the stations. Our laboratory will continue to analyze samples and the data will be processed and distributed as described in component (5). We are in the process of exploratory data analyses to look for relationships among driving factors (e.g., freshwater discharge) and patterns of hydrography, nutrients, and oxygen.

2. Continue monitoring direct atmospheric inputs of dissolved inorganic nitrogen to the NRE and Pamlico Sound to extend the ADN budget for the lower estuary.

3. Incorporate concentration data from the mouth of the South River with loading estimates from the Open Grounds Farm to estimate the relative contribution of the farm to the overall nutrient budgets of the NRE. A nitrogen budget is presently being developed for one of the major subtributaries of the South River that drains a large portion of the farm.

4. Modify and test the profiling instrumentation for deployment in Pamlico Sound to monitor hydrography and circulation in Pamlico Sound as part of the EPA Bioindicator Program.

5. In addition to the established protocol for data storage and distribution, we will build a searchable database using Microsoft Access. We plan to combine the water quality data from UNC, NCDWQ, and Weyerhauser with similar historical data collected by East Carolina University in the 1980s and other data on physical transport, sediment geochemistry, benthic population, and fishes. We hope to establish an invaluable information resource for all NRE researchers.

Journal Articles on this Report : 5 Displayed | Download in RIS Format

Other project views: All 82 publications 21 publications in selected types All 19 journal articles
Type Citation Project Document Sources
Journal Article Buzzelli CP, Luettich Jr. RA, Powers SP, Peterson CH, McNinch JE, Pinckney JL, Paerl HW. Estimating the spatial extent of bottom-water hypoxia and habitat degradation in a shallow estuary. Marine Ecology Progress Series 2002;230:103-112. R826938 (2000)
R826938 (Final)
R827957 (Final)
R828677 (2001)
R828677C001 (Final)
  • Full-text: MEPS-Full Text PDF
  • Abstract: MEPS-Abstract
  • Journal Article Luettich RA, Fleming J, McNinch J, Buzzelli CP. Circulation characteristics of the Neuse River Estuary, North Carolina. Estuaries 2000. R826938 (2000)
    not available
    Journal Article Luettich RA, Carr SD, Reynolds-Fleming JV, Fulcher CW, McNinch JE. Semi-diurnal seiching in a shallow, micro-tidal lagoonal estuary. Continental Shelf Research 2002;22(11-13):1669-1681. R826938 (2000)
    R826938 (2001)
    R826938 (Final)
    R828677C001 (2002)
    R828677C001 (2003)
    not available
    Journal Article Paerl HW, Bales JD, Ausley LW, Buzzelli CP, Crowder LB, Eby LA, Go M, Peierls BL, Richardson TL, Ramus JS. Hurricanes' hydrological, ecological effects linger in major U.S. estuary. Eos 2000;81(40):457-462. R826938 (2000)
    R826938 (Final)
    not available
    Journal Article Whitall DR, Paerl HW. Spatiotemporal variability of wet atmospheric nitrogen deposition to the Neuse River Estuary, North Carolina. Journal of Environmental Quality 2001;30(5):1508-1515. R826938 (2000)
    R826938 (Final)
    R825243 (Final)
  • Abstract from PubMed
  • Full-text: JEQ Full Text
  • Other: JEQ Full Text pdf
  • Supplemental Keywords:

    estuary, precipitation, nitrogen, ecosystem, aquatic, ecology, monitoring, Atlantic coast, North Carolina, NC., RFA, Scientific Discipline, Geographic Area, Water, Ecosystem Protection/Environmental Exposure & Risk, Nutrients, Ecology, Water & Watershed, Ecosystem/Assessment/Indicators, Ecosystem Protection, Chemistry, State, Monitoring/Modeling, Ecological Effects - Environmental Exposure & Risk, Air Deposition, Southeast, Biology, Watersheds, aquatic ecosystem, coastal ecosystem, environmental monitoring, eutrophication, hydrological stability, ecological exposure, risk assessment, fish kills, estuaries, coastal watershed, meteorology, bioavailability, coastal zone, esturarine eutrophication, algal growth, coastal environments, hypoxia, CISNet Program, anoxia/hypoxia, estuarine ecosystems, algal blooms, aquatic ecosystems, Neuse River Estuary, water quality, North Carolina (NC), stress responses, atmospheric deposition, land use, nitrogen, ecological response

    Relevant Websites:


    Progress and Final Reports:

    Original Abstract
  • 1999 Progress Report
  • Final Report