地下水中磷污染问题日趋显露，磷石膏堆场与农业复合区地下水中磷超标严重。磷石膏淋滤液含高浓度磷，呈强酸性，入渗农业区后其迁移、转化及归趋尚不明确。由于磷石膏堆场和农业源无法割裂，难以辨识堆场和农业源对地下水磷污染的贡献。本课题首先采用静态实验，研究不同质地包气带土壤和含水层介质对磷的吸附性能。其次，采用土柱模拟实验，探究酸性磷石膏淋滤液入渗农业区后，对包气带土壤理化特性及“固磷”性能的影响；同时，研究磷素在不同质地包气带土壤和地下水含水层介质中的迁移转化规律，考察主要环境因子的影响作用，并构建相应的迁移模型。最后，通过研究磷石膏淋滤液和农业源中磷素通过包气带土壤和地下水含水层介质后磷酸盐氧同位素的分馏效应，开展复合源区地下水中磷素的源解析。研究结果有助于厘清复合源区重点污染源和磷的重点迁移途径，以期为在重点迁移途径过程处建立治理和阻断技术体系提供理论基础和科学依据，突破盲目治理的技术瓶颈。

The phosphorus pollution in groundwater has been increasingly exposed. Previous research has indicated that there was serious phosphorus pollution in agricultural area and its groundwater environment near phosphogypsum stacking. The phosphogypsum leachate contains high concentration of phosphorous and it is strongly acidic. It is not yet clear that the migration, transformation and fate of the phosphorus permeating agricultural area. As the phosphogypsum stacking and agricultural source cannot be separated, it is very difficult to identify their contribution to the phosphorus pollution in groundwater. Based on the existing problems, this work firstly uses static to investigate the adsorption properties of phosphorus on soils and aquifers with different textures. Secondly, the soil column experiments are carried out to explore the influence of acidic phosphogypsum leachate on physicochemical properties and phosphorous fixation of soil in vadose zone after permeating agricultural area, and to investigate the migration and transformation law of phosphorus in different soil vadose zones and subsurface aquifer media under different environmental conditions and establish the corresponding migration models. Finally, the source apportionment of phosphorous in groundwater located in the agricultural area near phosphogypsum stacking is conducted by studying the δ18OP fractionation effect of phosphate from phosphogypsum leachate and agricultural source through soil vadose zones and subsurface aquifer media. The research results are helpful to clarify the key pollution sources and phosphorus migration routes in the composite source area and are expected to provide certain theoretical and scientific basis for identifying the key pollution sources and establishing the prevention and control technology system in the process of key migration routes.