Marginal water, like treated effluent or other types of wastewater, induces contaminant accumulation in different environmental compartments such as soil and groundwater. With a root zone model and daily rainfall data as input, accumulation in the case of two different degradation concepts was modeled: (I) the solute degrades only in the solution phase, and (II) the solute degrades in both the solution and the adsorption phase. For linear adsorption, both degradation concepts not only yield similar results, but adsorption does not affect the long‐term concentration. This can be readily explained with the governing equations. For nonlinear adsorption, the degradation concept does affect the concentration and fluxes. When the first concept is valid, the long‐term concentration is not affected by adsorption, whereas the short‐term and fluctuations are. For the second degradation concept, the long‐term average concentration and fluxes are also affected by adsorption. A correction factor was derived to correct the analytical solution of the time‐dependent concentration of nonlinearly adsorbing solutes. For all scenarios, reasonable estimates of the long‐term concentration could be obtained with analytical models for most parameter combinations, which can be used to identify contaminant species that should be prioritized for further research.

中文翻译：

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降解概念在废水灌溉中吸附污染物的作用

像处理过的废水或其他类型的废水一样，边际水会导致污染物在不同的环境区（例如土壤和地下水）中积累。使用根区模型和每日降雨数据作为输入，对两种不同降解概念下的累积进行了建模：（I）溶质仅在溶液相中降解，（II）溶质在溶液和吸附中均降解相。对于线性吸附，两种降解概念不仅产生相似的结果，而且吸附不会影响长期浓度。这可以通过控制方程式轻松解释。对于非线性吸附，降解概念确实会影响浓度和通量。当第一个概念有效时，长期浓度不受吸附的影响，而短期和波动是。对于第二个降解概念，长期平均浓度和通量也受吸附影响。推导了一个校正因子来校正非线性吸附溶质随时间变化的浓度的解析解。对于所有情况，可以使用大多数参数组合的分析模型获得长期浓度的合理估计值，该模型可用于识别应优先进行进一步研究的污染物种类。