为了评价灌区农田非点源磷素的流失风险,对内蒙古河套灌区典型作物地块中不同土层深度的土壤对磷素的吸附能力进行了测定,借助SPSS软件对试验结果进行统计分析,评价土壤磷素向水体的流失潜能以及可能的影响因素。结果表明:研究区不同地块的各层土壤均可以用Langmiur和Freundich方程来表征土壤对磷素的吸附特征,且Langmiur方程的拟合性要好于Freundich方程;小麦地块的各层吸附能力都较强,套种地块的吸附能力在试验中表现较差;表层土壤在不同地块的吸附能力差别不大,这可能与当地的复种习惯有关;表层土壤相对于深层土壤的流失潜能较高,即土壤中的磷素随农田退水的流失风险相对较大,但套种地块中磷素随渗漏淋失的潜能比对地表径流流失的潜能大;除Qm和EPC0之外,PSI值可以直接作为评价磷流失潜能的有效指标;磷素在农田地块的流失是河套灌区不可忽视的农业管理问题。该文为河套灌区科学合理施肥和非点源污染的防治提供了科学依据。 In order to evaluate the risk of non-point source phosphorus loss in irrigated farmland, the adsorption capacity of phosphorus to soil in different soil depths in typical crop plots of Hetao irrigation area in Inner Mongolia was measured. SPSS software was used to analyze the test results, Potential of phosphorus loss to water bodies and possible influencing factors. The results show that all the soils in different plots in the study area can use Langmiur and Freundich equations to characterize the adsorption characteristics of soil phosphorus, and the fitting of Langmiur equation is better than the Freundich equation. The adsorption capacity of each layer of wheat plots The adsorption capacity of the interplanted plots was poor in the experiment. The adsorption capacity of the topsoil in different plots was not different, which may be related to the local multiplication habit. The loss potential of the topsoil relative to the deep soil was higher, That is to say, the risk of phosphorus loss in the soil with the return of farmland is relatively large. However, the potential of phosphorus leaching with leakage in the intercropping plots is greater than the loss potential of surface runoff. In addition to Qm and EPC0, Directly as an effective indicator to evaluate the potential loss of phosphorus loss; the loss of phosphorus in farmland plots is an agricultural management issue that can not be ignored in Hetao Irrigation District. This paper provides a scientific basis for the scientific and rational fertilization and prevention and control of non-point source pollution in Hetao Irrigation District.