Studies on nutrients released from a Trinity River sediment under oxic conditions.

Nutrient interaction between sediment and overlying water under oxic conditions was investigated in continuous flow experiments. When exposed to 0.0 mg/l and 0.2 mg/l phosphorus in the overlying water, the Trinity River sediment released phosphorus to the water. But, when the initial phosphorus concentration in the water was 2.0 mg/l, the sediment removed phosphorus from the water. The phosphorus and other nutrients released from sidement supported algal growth. Consistently algal growth in the media that had sediment contact was greater than growth in a synthetic stand laboratory media with similar phosphorus and other nutrient concentrations. Hence, chemical analyses of nutrient concentrations released from sediments appear to be poor substitutes for bioassays in determining the eutrophication potential of this particular source.