Nutrient Thresholds Required to Control Eutrophication: Does It Work for Natural Alkaline Lakes?

The responses of phytoplankton to nutrients vary for different natural bodies water, which can finally affect the occurrence bloom. However, effect high alkalinity characteristic on nutrient thresholds alkaline lake is rarely considered. Bioassay experiments were conducted investigate and growth closed plateau Chenghai Lake, Southwest China, has a pH background up 9.66. community was restricted by phosphorus without obvious correlation with input nitrogen sources. This be explained fixation function cyanobacteria, meet their needs nitrogen. In addition, nitrate (NO3-N) could utilized more efficiently than ammonia (NH4-N) in Lake. Interestingly, eutrophication soluble reactive (SRP), NH4-N, NO3-N should targeted at below 0.05 mg/L, 0.30 0.50 respectively, are higher usual standards eutrophication. inhibition due damage cells. Therefore, prevention blooms considered from not only aspect reducing input, especially but also maintaining lake, formed geological saline-alkali soil.