Limnological Monitoring on the Upper Mississippi River System, 1993- 1996: Long Term Resource Monitoring Program Bellevue Field Station

摘要

Since 1988 the Long Term Resource Monitoring Program (LTRMP) staff have performed basic limnological field measurements in the Upper Mississippi River System. The period of this report (1993-1996) includes a major revision of the LTRMP sampling design in 1993 that added randomization broader spatial coverage and increased monitoring of tributaries and locations that allow monitoring of material transport. Several short-term trends were noted during 1993-1996. Total nitrogen nitrate-nitrite nitrogen soluble reactive phosphorus total phosphorus and turbidity generally decreased while ammonia increased in all study pools 12 13 and 14. Sediment and plant nutrient concentrations were higher in two tributaries (the Maquoketa and Wapsipinicon Rivers, Iowa) than in the main channel of the Mississippi River.