Deep lakes usually have long water exchange period, high pollutant retention rate, and vertical thermal stratification,therefore large spatiotemporal variability may exist in the water body. Based on the two field surveys in May and July 2009 to investigate the horizontal and vertical variations of phosphorus in Lake Fuxian, the influences of main polluting sources and hydrodynamic conditions are analyzed and the distributions of phosphorus in the lake are studied. Results show that the distribution of TP in the surface water agrees with the wind-induced surface flow and the distribution of main polluting sources. The concentrations of TP in the surface water in July are obviously larger than those in May, which is mainly caused by pollutants in runoff in the rainy season. However, the water below 100 m and more is less affected by the runoff pollutions. Besides, TP concentration has an increasing trend along the water depth. The accumulation of phosphorus in deep water is heavy and the situation is getting more serious. The existence of "a phosphorus pool" at the bottom is a big potential threat to the whole water body, which needs more attention.

Lake Fuxian  /  phosphorus  /  distribution  /  hydrodynamics