我国非点源负荷研究中的问题探讨

在非点源研究实践和查阅大量非点源文献的基础上,总结出我国非点源负荷估算中通常使用的4种方法,即断面实测总负荷减去统计的点源负荷法、单位负荷法、水文线分割法和SWAT模型估算法.分析对比了这些方法在我国和北美地区使用条件的不同和使用过程中的差异,讨论了这些方法在使用中可能产生的错误.研究结果表明,在我国目前情况下前3种方法会相当程度地高估非点源负荷量,而SWAT模型在我国的应用没有充分体现其"分布式"模型的特点;同时,由于北美和中国的情况存在较大差异使得北美地区不同土地使用方面的校正数据在中国并不可用,导致在径流模拟方面也存在很大误差,因此,负荷计算将产生更大误差.在此讨论基础上,提出了在我国农业非点源负荷研究中需注意的若干问题,并结合目前我国环境现状,提出了对国内非点源污染研究和控制的见解.

Problems and recommendations for non-point source pollution identification in China

Non-Point Source(NPS)pollution is a new field of study in China.Four estimation methods for NPSload that have been used in China are summarized.These are total measured load in a section minus reported point source loads,unit load method,hydrograph separation method and SWATmodel estimation.The conditions for the use of these methods in China and North America were analyzed,and the differences in application of these methods between two areas were contrasted.The authors also discussed the probable errors resulting from using these methods to estimate NPSload in China,and believe that the first three methods would overestimate NPSload in Chinese situations to a large degree.The application of the SWATmodel in China has not been characterized as a "distribution physical model",for which calibration data for individual land types for runoff are not available in China and which is also likely to lead to substantial errors as the American situation is very different than in much of China.Finally,some recommendations for NPSload study and NPSpollution control are proposed.