流域污染物通量测算方法研究

流域水系内污染物通量不仅能够用于评价各类污染源的水污染物入河负荷,也是对流域污染特征,水污染物在河流水体中复杂迁移、转化过程的最直观反应。准确测算流域水系内污染物跨界通量及其时空分布是进行流域水环境风险预警和风险管理的重要前提之一。针对目前多种污染物通量测算方法在进行污染物年通量估算时,结果不确定性大这一突出问题,以流域水质监测站年内逐日流量、悬浮颗粒物监测数据作为悬浮颗粒物年通量参考值,基于以月、半月、周为周期的监测策略,将逐日流量、悬浮颗粒物监测数据重新筛选抽样构造,由此,系统分析了不同流域集水面积、污染通量监测频次和目前常用通量估算方法对污染物年通量估算不确定性的影响。所得方法和结论可为进一步制定流域污染物通量的测算规范提供方法指引和技术支持。

Investigation of Monitoring Strategies Estimation Methods for Watershed Pollutant Fluxes

Within a watershed system,pollutant fluxes can not only be used to evaluate various sources of water pollutant loads into the river,but also directly reflect watershed pollution characteristics,as well as complex migration and transformation of water pollutants.One of the key programs for water environment risk warning and management is to accurately measure pollutant trans-boundry fluxes within the water system,together with their spatial and temporal distribution.In terms of the outstanding bias and imprecision of annual pollutant fluxes under the situation of infrequent surveys and different estimation methods,the paper extracts and re-constructs suspended particulate matter concentrations and corresponding water discharges from daily database in watershed based on monthly,bio-monthly or weekly monitoring strategy,and than,the impacts of watershed area,monitoring frequency and different estimation methods on the uncertainty of annual pollutant fluxes estimation are investigated systematically.Results and methodology are able to offer guidance and technical support for further formulation of measurement criterion of watershed pollutant fluxes.