Land Water Interactions: Effects of Introduced Nutrients and Soil Particles on Reservoir Productivity

摘要

Laboratory studies with experimental water columns and field studies in a lake were undertaken to examine the effects of introduced nutrients and suspended soil particles (SSP) on organic matter production in man-made impoundments. Watershed runoff experiments and in place monitoring of inflow events in the lake showed that turbidity associated with river-borne (SSP reduced the euphotic layer thickness, inducing light-limited phytoplankton (PP) photosynthesis in a larger portion of the water column. Nutrient desorption from SSP enhanced nutrient availability for PP and bacterioplankton (BP) production, and was dependent on soil nutrient composition. Increased nutrient availability associated with watershed inflow stimulated PP production in the water column euphotic layer. Highly turbid watershed runoff caused vertical displacement of PP cells in laboratory water columns and during runoff events in the lake.