A Soils-Based Approach to Assess Salt Marsh Degradation. (6318)
Authors:
T. Twohig - University of Rhode Island M. Stolt* - University of Rhode Island J. Turek - NOAA, Narragansett, RI C. Wigand - EPA, Narragansett, RI
Abstract:
Despite numerous functions and values, half of the Unites States’ estuarine wetlands were lost by the 1970’s. Many of the marshes that were not completely destroyed may have been altered in some capacity. The objective of this study was to develop a protocol for rapidly assessing the amount of degradation that has occurred within marshes that have been altered by tidal restriction. The physical and chemical characteristics of two tidally restricted New England marshes were compared to nearby healthy reference marshes. Field measurements included bearing capacity estimates based on loading intensity and penetration resistance, and percent stable plant fragments based on a volume basis. Rapid laboratory analysis included measurements of pH, potential acidity, and stable plant fragments on a percent weight basis. Tidally restricted marshes had significantly lower (alpha = 0.05) amounts of stable plant fragments and lower bearing capacity values, suggesting that the inundated marsh peat has
decomposed and become unstable. Initial surface pH of the restricted marshes were significantly higher than surface layers of the reference marshes. These results suggest that rapid field and laboratory techniques can be used to provide an index of the degree of degradation that has occurred to a marsh as a result of tidal restriction.
Speaker Information: Mark Stolt, University of Rhode Island, 1 Greenhouse Road 112 Kingston Coastal Institute Building Dept. of NRS University of Rhode Island, Kingston, RI 02881; Phone: 401-874-2495;
E-mail: [email protected]
Session Information: Tuesday, November 2, 2004, 3:00 PM-5:00 PM Presentation Start: 3:00 PM (Poster Board Number: 1644) Keywords: salt marsh; estuaries; peat; rapid assessment