摘要：Nuisance periphyton growth influences the aesthetics, recreation, and aquatic life of waterbodies Partners Lake is a shallow springfed lake in the headwaters of the Illinois River Watershed in Cave Springs, Arkansas, that experiences nuisance growth of periphyton (ie, Spirogyra spp) each year The ratio of dissolved nitrogen (N ~50 mg L1) and phosphorus (P ~0030 mg L1) in the lake water (N:P≥288), as well as nutrient limitation assays, suggests that periphyton growth should be Plimited While the water column lacks sufficient P to promote growth, the sediments have the ability to release P to the overlying water; Pflux ranged from 163 mg m2 d1 to over 10 mg m2 d1, reaching final concentrations of 008 to 034 mg L1 However, soluble reactive phosphorus concentrations were consistently at or below 0030 mg L1, in the lake, suggesting that the periphyton were likely immobilizing P as quickly as it was released from the sediments In the lab, maximal periphyton growth (~30 to 35 mg m2) occurred in the 010 to 025 mg L1 P treatments, over a 6 day incubation period Similar levels of growth occurred when lake sediments were the P source, suggesting P released from the sediments is sufficient to support nuisance algal growth We need to begin managing the legacy P stored in the sediments, in addition to external P loads, because internal P can sustain nuisance periphyton biomass when N is not limiting.
