针对洱海富营养化加剧以及蓝藻水华问题,应用Aquatox模型对洱海水环境进行模拟,确立了一套适用于洱海生态系统的特征参数,并将模拟结果与实测数据进行验证.验证结果表明模型较好地模拟了常规水质和藻类演替变化,与实际水环境状况大体吻合.以此为基础选取TN、TP和Chl.a指标对洱海营养物与富营养化状态的投入响应关系进行模拟研究.结果表明,洱海对于外界营养物输入比较敏感,对氮磷输入增减反应明显；外界氮磷的削减都对Chl.a含量有降低作用,TN的作用更加明显；氮磷的增加对于Chl.a含量都略有提升；同时调控氮磷具有协同作用,对Chl.a含量影响效果最明显；当水体TN浓度在0.34 mg/L的阈值以下水平,即洱海外源TN输入量削减比例达到43.3％以上时,藻类优势种由蓝藻变为硅藻,水体Chl.a含量大幅降低,有效抑制富营养化进程.%Lake Erhai is suffering from eutrophication and frequent cyanobacteria blooms. Based on the Aquatox model, this study simulated the routine water quality dynamics and the annul succession of algae, established a set of parameters applicable for the Lake Erhai ecosystem, and validated the simulation results. Though there is a little difference in the trend of TP with measured data, water-temperature,TN and Chi. A concentration were all well coincided with measured data. In addition, this paper tries to discuss the response of eutrophic state(TN,TP,Chl. A) to nutrient input(nitrogen and phosphorus). The results show that Lake Erhai ecosystem is sensitive to the nutrient input. Comparing to the TP regulation, TN regulation has a more significant effect to CM. A concentration especially when it was reduction control. They both can increase the Chi. A concentration in a small degreed. There is an enhanced coordinated effect in Chi. A decreases when regulating TN and TP at the same time. Furthermore, if the TN concentration is kept at or under the threshold of 0.34 mg/L, which means to cut the TN input more than 43.3% as before,the eutrophication process can well be restrained with a change in the dominant algal specie and a sharp fall of Chi. A concentration.
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