Evaluation of the Effect of Benthic Barrier Placement on Sediment Physical andChemical Conditions

摘要

Investigations examining the effects of benthic barrier placement on sedimentphysical and chemical conditions, interstitial water, and surficial water were conducted in Eau Galle Reservoir, Wisconsin, and Lake Guntersville, Alabama. Long-term physical and chemical effects were minimal when barriers were placed on relatively coarse-textured sediments. On fine-textured sediments, however, physical effects were more pronounced and evidenced by decreases in sediment moisture content, increases in sediment density, and decreases in sediment organic matter content. The most pronounced effects of barrier placement were an increase in ammonium-nitrogen and a decrease in iron concentrations in the interstitial water of fine-textured sediments. Anoxic conditions were found in the surficial water beneath placements at all study sites. No significant differences were evident in the growth of aquatic plants on sediments following long-term barrier placements.