河流营养物参照状态的建立方法研究进展

建立营养物参照状态是河流水污染控制的关键问题之一。系统论述了参照状态的各种内涵,重点分析了国外建立河流营养物参照状态的各种方法及优缺点,并分析了其在中国的适用性。最后,提出了河流营养物参照状态的进一步研究的重点。参照状态根据允许人类活动影响的程度可有多种含义:最小干扰状态、历史状态、最少干扰状态和最佳可达成状态。其中,最少干扰状态和最佳可达成状态在现实管理中具有一定程度的可操作性。参照河流百分比法是建立营养物参照状态的首选方法,但中国水环境污染形势严峻,参照点变得越来越少。当参照点不存在时,一般河流百分比法是参照河流百分比法的替代方法,然而一般河流百分比法和参照河流百分比法的匹配性关系并不完全保持一致。由于栖息地退化等因素对生物完整性的影响程度可能比营养物浓度更大,生物响应法在实际应用中是非常困难的。流域模型法虽然有众多优点,但是数据要求较高,并且常用流域模型的机理与中国有较大差距,在中国应用的结果具有较大的不确定性。综合考虑中国水环境污染现状和数据要求,以多元线性回归模型为代表的简易模型方法在中国应有最大的适用性。然而,环境因素与营养物质间的关系往往都是非线性的,今后应着重研究建立河流营养物参照状态的多元非线性回归模型方法。此外,还应加强季风河流营养物参照状态的季节性差异与年际差异研究,并在全国层面上根据自然因素划分适当规模的生态区,分区确定各生态区的河流营养物参照状态。

Research Advances in Technology Methods for Establishing River Nutrient Reference Conditions

Establishing reference conditions of nutrients is one of the key issues for river water pollution control.The various connotations of the reference condition were systematically discussed,and the various establishing river nutrient reference conditions abroad methods and their advantages and disadvantages were analyzed,and their applicability in China was analyzed.Finally,the emphasis of further research on the reference condition of river nutrients was proposed.The reference condition could have multiple meanings according to the extent to which human activity is allowed to affect:minimally disturbed condition,historical condition,least disturbed condition,and best attainable condition.Among them,the l least disturbed condition and the best attainable condition had a certain degree of operability in realistic management.The reference river percentage method was the preferred method to establish reference conditions of nutrients,but the situation of water pollution in China was severe,and reference points were becoming fewer and fewer.When the reference point did not exist,the general river percentage method was an alternative to the reference river percentage method.However,the matching relationship between the general river percentage method and the reference river percentage method was not completely consistent.As the impact of habitat degradation and other factors on biological integrity may be greater than the concentration of nutrients,biological response methods were very difficult in practical applications.Although the watershed model method had many advantages,the data requirements were high,and the mechanism of the commonly used watershed model was far from that of China,and the results applied in our country had greater uncertainty.Considering comprehensively the current situation of water pollution in China and data requirements,the simple model method represented by multiple linear regression model should have the greatest applicability in China.However,the relationship between environmental factors and nutrients was often nonlinear.In the future,research should be focused on establishing a multivariate non-linear regression model method for river nutrient reference conditions.In addition,research on seasonal and interannual differences in the reference conditions of nutrients in monsoon rivers should be strengthened,and ecological regions of appropriate scale should be divided at the national level according to natural factors,and the reference conditions of river nutrients in each ecological region should be determined by district.