Suspended solids in Missouri reservoirs in relation to catchment features and internal processes.
Mean total suspended solids (TSS), in 135 Missouri reservoirs range from 1.2 to 47 mg/l. The volatile (VSS) and non-volatile (NVSS) fractions range from 0.6 to 9.6 mg/l and 0.5 to 37 mg/l, respectively. %NVSS is the larger fraction and declines through summer as %VSS increases. Suspended solids (particularly VSS) correlate with metrics of lake trophic state and are positively related with the proportion of cropland (%C, r = 0.69-0.74) in their catchments, negatively related with forest cover (r = -0.54 to -0.56), and weakly related with grassland (r < 0.31). Regressions including %C with dam height (representing morphometry) and flushing rate (representing hydrology), explain approximately 70% of cross-system variation in TSS and 67% in VSS. Dam height and %C explain 57% of variation in NVSS. Residual analysis shows statewide models under-predict suspended solids in urban reservoirs. Effects of catchment features on summer TSS largely reflect internal plankton growth mediated by influent nutrients (affecting VSS) over direct sediment input (affecting NVSS).
Jones
John R
JR
Department of Fisheries and Wildlife Sciences, University of Missouri, Columbia, MO 65211-7240, USA. jonesj@missouri.edu
Knowlton
Matthew F
MF
D002734:Chlorophyll / Q000378:metabolism; D004784:Environmental Monitoring; D005618:Fresh Water / Q000032:analysis; D008923:Missouri; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D012044:Regression Analysis; D014873:Water Pollutants / Q000032:analysis*; D014881:Water Supply / Q000032:analysis*
D014873:Water Pollutants; D002734:Chlorophyll; D010758:Phosphorus; D009584:Nitrogen