DOI: 10.5063/aa/duc_merp.30.12
title: Marsh Ecology Research Program (MERP): Sediment bulk density and percent organic matter data (1986-1989)

description: The Marsh Ecology Research Program (MERP) was a long-term interdisciplinary study on the ecology of prairie wetlands. A scientific team from a variety of disciplines (hydrology, plant ecology, invertebrate ecology, vertebrate ecology, nutrient dynamics, marsh management) was assembled to design and oversee a long-term experiment on the effects of water-level manipulation on northern prairie wetlands. Ten years of fieldwork (1980 -1989), combining a routine long-term monitoring program and a series of short-term studies, generated a wealth of new and diverse information on the ecology and function of prairie wetlands (Murkin, Batt, Caldwell, Kadlec and van der Valk, 2000). This data set includes sediment bulk density and percent organic matter data, collected as part of the physical environment section of MERP. Several aspects of the physical environment have important bearings on the measurement or estimation of variables critical to understanding nutrient cycling. Some of these relate to hydrology, others to sediment structure, and some to chemical and biological processes or states. The measures of the physical environment were chosen to provide data to help calculate or interpret processes important to nutrient cycling. These include soil and water temperatures, water levels, sediment bulk density and organic matter, sediment nutrient content, suspended solids import and export and bottom contours. Import - export nutrient budgets depend on good hydrologic data, an important part of which is the volume of water present at a given water level. Hence data on bottom topography were essential for calculating water level – volume relationships. Similarly, significant amounts of sediment pumped with water into or out of the ponds could have important long term impacts on bottom sediment composition and topography. Finally, sediment bulk density and organic matter determine the relative quantities of water and solids in a volume of sediment, which has an important bearing on the quantities and distributions of many chemical species in the plant rooting volume. Because these physical attributes do not change rapidly with time, measurements were needed less frequently in the MERP. Input and output of suspended solids in pumped water were determined monthly, sediment bulk density and organic matter twice a year, and contours once early in the study with later spot checks (Kadlec, 1989). From 1980-1985, sediments were characterized by nutrient analysis and an initial particle analysis (1979; note that this data is not stored on the KNB but can be obtained by contacting the Institute for Wetland and Waterfowl Research, Ducks Unlimited Canada). Following 1985, sediments were characterized by bulk density and percent organic matter (1986-1989), in addition to the initial particle analysis. Note that other portions of the physical environment section of MERP, including soil and water temperatures, water levels, sediment nutrient content, and suspended solids import and export, are contained within separate data packages on the KNB. For further information on the Marsh Ecology Research Program (MERP), please visit: http://www.ducks.ca/conserve/research/projects/merp/index.html References: Kadlec, J.A. 1989. Chapter 3: Physical environment. In: Marsh Ecology Research Program: Long-term Monitoring Procedures Manual. (Eds.) E.J. Murkin and H.R. Murkin, pp. 6-7. Manitoba, Canada: Delta Waterfowl and Wetlands Research Station. Murkin, H.R., B.D.J. Batt, P.J. Caldwell, J.A. Kadlec and A.G. van der Valk. 2000a. Introduction to the Marsh Ecology Research Program. In Prairie Wetland Ecology: The Contribution of the Marsh Ecology Research Program. (Eds) H.R. Murkin, A.G. van der Valk and W.R. Clark. pp. 3-15. Ames: Iowa State University Press.