Submitted to: Riparian Ecology and Management in Multiland Use Watersheds Meetings
Publication Type: Abstract Only
Publication Acceptance Date: December 22, 2000
Publication Date: N/A
Technical Abstract: The capacity of wetland systems to capture sediments and build up areas of deposition has been documented as well as ablilty of such systmes to store substantial amounts of C. The purpose of this study was to determine the rates of sediment deposition and C storage in a wetland site adjacent to a small first-order stream that drains an agricultural area. The soils of the esite consist of a histosol buried by sediments from the agricultural area. Samples of deposited sediments in the riparian zone were collected in 5 cm increments and the concentration of Cs-137 was used to determine the 1964 and 1954 deposition layers. Agricultural activity in the watershed has caused large sediment deposition to the wetland and deposition rates for the 1964 to 1999 period were less than those for the period from 1954 to 1964. Changes in rates of deposition between the two periods probably reflect changes in agricultural practices. The decrease in rate of mineral soil deposition relative to that of C in the ecosystem was reflected in high C enrichment within the top layer (ca. 5 cm) of the mineral sediment. Results indicate that the increases in sediment deposition caused by agriculture has substantial influence on the rate of C storage in the wetland.