地下水补给对河流水质模型的影响

以经典的一维水质模型及其解为基础,将地下水对河流的补给作用作为河流水质模型的一项影响因子,利用迭加原理,给出受到沿途地下水补给影响下的河流水质模型的解析解.利用这一新解析解,定量研究地下水补给作用对河流水质模型参数的影响规律.地下水渗出(相当于一点污染源)进入河流后,在随河水向下游运移的过程中,其水质浓度也将发生衰减."连续线源"对河流水体中溶质衰减过程的影响,不简单等同于几个"点源"的迭加.含水层与河流间水量交换作用,更宜用"连续线源"去刻画.以颖河为例,河流两岸潜水补给对河流水质模拟计算的影响程度研究表明,地下水补给对河流溶质沿河变化规律的影响,理论上不能用"综合衰减系数k值"简单反映,而且它对k值计算影响相当大.

Stream-Water Quality Modelling with Influence of Groundwater Recharge

Based on the 1-D water quality model of stream,which taking into account the continuous discharge of groundwater along the stream way,a new analytical solution is proposed by superposition theorem.According to this new analytical solution,parameters estimation of stream water quality model response to groundwater discharge is analyzed quantitatively.The solute concentration decays when the groundwater discharge,a spot of pollution source,enters to streams and moves to lower reaches.The influence of seriate line-source to the decay of solute concentration in streams is not simply equal to the addition influence of several point-sources.It refers to line-source when describing the water exchange between aquifers and streams.Taking Yinghe River,Anhui Province as an example,the study of the deviation degree of parameters estimation of stream water quality model due to groundwater discharge shows that,the influence of the groundwater discharge to the variation rule of solute long streams,which affects the comprehensive attenuation coefficient k greatly,cannot be described simply by k in theory.