数字滤波法在点源和非点源污染负荷分割中的应用

以分辨流域点源和非点源污染负荷为研究目标,在傅立叶分析的基础上,提出了从污染负荷时间序列中分辨点源和非点源污染负荷的新方法——数字滤波法,探讨了数字滤波方程的参数与滤波次数的关系,并将该方法应用到东江流域CODMn负荷的分割上.应用实例表明,分割的点源和非点源负荷系列曲线符合点源和非点源负荷的产生特点,使用者能够在污染负荷分割过程中通过滤波参数的选取比较方便地加入自己的经验.一般取较大滤波参数时,只需要3次滤波就能得出较满意的结果.

Application of a Digital Filter in the Differentiation of Pollutant Loads from Point and Non-Point Sources

This study aims to differentiate pollutant loads originating from point and non-point pollutant sources. Based on Fourier analysis techniques, a new method, digital filter, was developed with the aim to distinguish whether the pollutants are of point source or of non-point source through the time sequence of pollutant load. The relationship between parameters of filter equations and number of filter computations was discussed. This technique was successfully applied to the differentiation of pollutant loads in terms of COD_(Mn) in the East River basin. The results of this case study indicate that this newly-developed method has high maneuverability and is easy to use with a simple algorithm. The differentiated pollutants can well match the actual conditions. Additionally, the parameters of the newly-developed technique can be altered to well capture the changing properties of pollutants originating from point or non-point sources, which indicates larger flexibility of this technique in practice. Generally, satisfactory results can be obtained after filtering only three times by selecting larger filter parameters.