中文摘要：

以中小型河流为研究对象，通过对稳态的水平二维移流扩散方程解析解的分析，导出任意连续点源排放污染带特征参数LM、LB的计算公式。在考虑中心和岸边排放特殊情况下的计算公式与Fischer等人推导的公式一致。此研究将有助于排污单位和水质管理部门科学决策污水处理程度和最佳排放方式，以达到污水排放最优化管理。

英文摘要：

Taking the middle and small rivers as study object, according to the analysis of the analytical solutions ot steady horizontal two-dimensional diffusion equation, the calculation formula for characteristic parameters LM and LB of random continuous point sources pollution emissions is derived in this paper. The formula under the condition of considering emissions from the special circumstances of the center and the shore is agreed with the one derived by Fischer. This study will help the sewage and water management departments to scientifically decide the sewage treatment level and the best discharge type to achieve the optimal management of sewage discharge.