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Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds
Published on: September 26, 2017
Nutrient concentrations in Maryland non-tidal streams
Raymond P Morgan1, Kathleen M Kline
1Appalachian Laboratory, University of Maryland Center for Environmental Science, 301 Braddock Road, Frostburg, MD 21532-2307, USA. rmorgan@umces.edu
Environmental Monitoring and Assessment
|October 5, 2010
Summary
Maryland streams show high nutrient levels, particularly total nitrogen (TN) and total phosphorus (TP), linked to land use. Exceeding criteria, these nutrients impact stream health and flow into the Chesapeake Bay.
Area of Science:
- Environmental Science
- Ecology
- Water Quality
Background:
- Small-order, non-tidal streams are crucial aquatic ecosystems.
- Nutrient loading from surrounding watersheds can significantly impact stream health.
- Understanding nutrient dynamics is vital for effective watershed management.
Purpose of the Study:
- To analyze nutrient relationships in Maryland's small streams.
- To assess nutrient loading against established criteria.
- To estimate stream kilometers impacted by nutrient pollution.
Main Methods:
- Utilized the Maryland Biological Stream Survey (MBSS) database.
- Correlated nutrient levels with land use (agriculture, forest) within sampling areas.
- Applied derived nutrient criteria to estimate affected stream lengths.
Main Results:
- Strong linear correlations found between nutrient levels and surrounding agricultural/forested land.
- Mean total nitrogen (TN) and total phosphorus (TP) exceeded Maryland's reference criteria in most watershed basins.
- Significant percentages of stream kilometers (up to 90% for TP) exceeded nutrient criteria in several basins.
Conclusions:
- Recommended upper stream TN criteria of 1.34-1.68 mg/L and TP criteria of 0.025-0.037 mg/L.
- Elevated TN and TP in non-tidal streams contribute to nutrient loading in the Chesapeake Bay.
- Protecting small stream integrity requires addressing nutrient inputs from watershed basins.
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