关键词: 水生态系统, 稳态转化, 富营养化:控制策略, 滇池

Abstract: With rapid increase in local population and of consequences of massive municipal and industrial sewage discharged into the lake,pollution of the Dianchi Lake has been deteriorated since the 1980s.The lake is in a status of heavy eutrophication,accompanied with cyanobacteria bloom.During the past decade,many pollution control projects have been implemented in the Dianchi Lake to eliminate external nutrient loads and improve the water quality.However,after the vast capital has been injected,the nutrient level still stays at an unacceptable level,although external pollutant load has been gradually reduced to a bit lower level.On the other hand,the characteristics of shallow lake dominating the water quality of the lake is insensitive to the reduction of external nutrient loads.In this paper,we analyze the evolution process of eutrophication in the Dianchi Lake and elaborate how human activities damaged the ecosystem in the lakeside zone and accelerated the eutrophication process.The existing pollution control projects,which cost too much,can hardly meet the requirements of nutrients control.According to the stable states theory and the simulation of the relationship between nutrition degree and algae outbreak in the Dianchi Lake,we believe that there exists a probability to recover the ecosystem in Dianchi Lake from turbid state to clear state,from phytoplankton dominated state to plants dominated state.Thus,we suggest that the projects of ecosystem recovery in the Dianchi Lake should be implemented by combining pollutant control with ecological restoration.

Key words: ecological management, stable state theory, eutrophication, Dianchi Lake