Abstract In the present work, the model of diffuse pollution of the rivers by conservative components is considered on the basis of advection - diffusion equation. The asymptotic solutions of the equation are analyzed, and typical structures of stationary fields of pollutant concentration in the river are established. The model was tested using the measurements of pollutant concentrations on the reach of the lowland Barnaulka River (Russian Federation, Altai Region), with homogeneous composition of soils in the catchment. The method of optimization was used to calculate the mass flow rate of dissolved pollutants at different catchment areas of different lengths. The adequacy of the proposed model was checked using the determination factor. Based on the considered criteria, the method of splitting the complex concentration fields into elementary areas, within which the mass flow rate of pollutant can be considered unchanged, is proposed.

中文翻译：

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低地小河流扩散污染下污染物流量估算方法

摘要 在目前的工作中，在对流-扩散方程的基础上，考虑了保守成分对河流的扩散污染模型。分析了方程的渐近解，建立了河流中污染物浓度平稳场的典型结构。该模型使用对低地巴尔瑙尔卡河（俄罗斯联邦，阿尔泰地区）河段污染物浓度的测量进行了测试，集水区土壤成分均匀。采用优化方法计算不同长度不同集水区溶解污染物的质量流量。使用决定因子检查所提出模型的充分性。根据考虑的标准，