频率分布法在淀山湖富营养化控制氮、磷基准制定中的应用

水质基准是制定水质标准的重要依据，以淀山湖为例，基于淀山湖25 a来的监测数据，通过数据分析的方法，探讨了在难于找到参照水体情况下水质基准的制定方法。根据淀山湖氮、磷变化趋势，并结合湖泊生态系统特征，初步可将1985～1996年淀山湖水质状态作为淀山湖富营养化控制的氮、磷基准制定参照状态。在参照状态的基础上，结合频率分布法，提出了淀山湖氮、磷的推荐基准值。建议TP的基准值为0080 mg/L。由于TN季节变化明显，TN基准值分为冬春季节与夏秋季节两个时期，建议TN冬春季节基准值为213 mg/L，夏秋季节基准值为077 mg/L。与太湖TP、TN推荐基准值相比，淀山湖推荐基准值高于太湖，综合考虑两个湖泊特征与营养物响应特征，该基准值仍然具有对淀山湖富营养化控制标准的制定具有科学性与指导性

RESEARCH ON NUTRIENT CRITERIA ESTABLISHMENT IN DIANSHAN LAKE BY THE FREQUENCY DISTRIBUTION METHOD

Eutrophication has been identified as the leading cause of impairment to Dianshan Lake.To address the issue of nutrient enrichment,government has established many nutrient management plans.It appears hard to approach exist water quality standards due to no criteria set for eutrophication.In this paper,based on 25 years nutrient data,we discussed the statistical method to set quality criteria for total P(TP) and total N(TN) and compared them with existing Taihu criteria.We calculated potential nutrient criteria by time series analysis and frequency distribution methods.The recommended criteria value of TP was 0.080 mg/L.The contents of TN were higher in the cold season than in the warm season.We divided TN in winter-spring and summer-autumn periods for analysis.The recommended criteria value of TN in winter-spring time and summer-autumn time were 0.77 mg/L and 2.13 mg/L,respectively.