非点源污染引发的水环境质量退化是我国目前面临的一个十分严峻的环境问题，实现农业非点源污染的有效控制是当前面临的一个关键问题。然而，近年来的研究发现非点源污染不仅仅局限于地表水体，因农业生产活动等导致的基流非点源污染也会给水体带来污染风险。黄垒河流域属于我国北方地区典型的农业型流域，面临着严峻的农业非点源污染问题，而基流有可能是流域氮、磷污染负荷输出的主要方式，对于流域的非点源污染有着极其重要的影响。因此，对流域的基流非点源污染特征展开研究具有十分重要的意义。本研究主要研究了黄垒河流域的基流非点源污染特征及其对未来土地利用变化的响应，首先模拟了黄垒河流域的非点源污染物，对流域的非点源污染负荷量进行了估算，对非点源污染负荷的时空分布特征进行了分析；在此基础上，估算了流域的基流量及基流非点源污染负荷量，分析了流域的基流非点源污染负荷的时空分布特征，并探讨了基流及基流非点源污染负荷的空间尺度效应；最后对2030年的土地利用情景进行了预测，分析了未来土地利用情景下的基流和基流非点源污染负荷的变化情况，主要研究结果如下：
（1）本文对黄垒河流域的非点源污染特征进行了研究。流域的非点源污染物时空分布特征表现为：在时间上，从年际变化来看，2016-2018年TN、TP污染负荷流失量表现为逐年增加的趋势，从年内季节变化来看，夏季（6-8月）TN、TP的非点源污染负荷流失最多，TN、TP输出负荷占全年输出总负荷的多年平均比例分别为79.31%、90.12%，从年内变化来看，在年内时间分布上表现为汛期（雨季）较高，非汛期（非雨季）较低的特点，8月输出负荷量达到最大，TN、TP输出负荷占全年输出总负荷的三年平均比例分别为65.91%、67.83%；在空间上，流域的多年平均TN、TP输出负荷表现为东北地区低、东南地区高的特点，其中13号子流域的TN和TP负荷输出强度最高，2号子流域的TN和TP负荷输出强度最低；在所有土地利用类型中，耕地的TN、TP负荷的输出强度和输出量都是最高的。
（2）本文对黄垒河流域的基流非点源污染特征进行了研究。流域的基流指数、基流非点源污染均表现出显著的时空分布特征，在时间上，从年际变化来看，2016-2018年的基流指数、基流对总径流的TN、TP污染负荷的贡献率表现为逐年减少的趋势，从年内变化来看，各月份的基流指数、基流TN、TP负荷贡献率的多年平均值均超过60%，8月份的基流指数、基流TN、TP负荷贡献率最低，分别为63.22%、65.50%、67.46%，1月份的最高，所有贡献率均达到98.44%；在空间上，汛期与非汛期的基流指数、基流TN、TP负荷贡献率空间分布特征基本一致，表现为东高西低的特点，在汛期，14号子流域的基流指数、基流TN、TP负荷贡献率最大，6号子流域的基流指数、基流TN、TP负荷贡献率最小。在空间尺度效应上，从源头小流域到流域出口，基流量、基流的非点源污染负荷量显著增加，基流指数、基流的非点源污染负荷贡献率普遍增加，但是随着空间尺度的增大，这些值也随之减小，表明随着流域面积的扩大，降水对基流、基流非点源污染物的影响在不断减少，同时发现土地利用分布、支流输入是基流和基流非点源污染空间尺度效应的重要原因。
（3）本文对未来土地利用情景下基流非点源污染特征进行了研究。利用FLUS模型对未来土地利用变化进行了预测，以研究区现有的数据为基础，对自然发展情况下的2030年土地利用情景进行了模拟。在自然发展情况的2030年土地利用情景下，对于全流域来说，黄垒河流域的基流指数与基流TN、TP负荷贡献率无明显变化，但是在上游源头流域和下游冲积平原地区，河流的基流指数与基流TN、TP负荷贡献率有一定程度的减少。

The degradation of water environment quality caused by non-point source pollution is a very serious environmental problem that my country is currently facing, and the effective control of agricultural non-point source pollution is a key issue currently facing. However, recent studies have found that non-point source pollution is not limited to surface water bodies, and base-flow non-point source pollution caused by agricultural production activities can also bring pollution risks to water bodies. The Huanglei River Basin is a typical agricultural watershed in northern my country, and it faces severe agricultural non-point source pollution problems. The base flow may be the main way for the output of nitrogen and phosphorus pollution load in the basin, and it has a significant impact on non-point source pollution in the basin. Extremely important influence. Therefore, it is of great significance to study the characteristics of non-point source pollution in the basin's base flow. This study mainly studies the characteristics of base-flow non-point source pollution in the Huanglei River Basin and its response to future land use changes. First, it simulates the non-point source pollutants in the Huanglei River Basin and the non-point source pollution load in the basin. Estimated and analyzed the temporal and spatial distribution characteristics of non-point source pollution load; on this basis, estimated the base flow and base flow non-point source pollution load of the basin, and analyzed the base flow non-point source pollution load of the basin. The spatial and temporal distribution characteristics of base flow and base flow non-point source pollution load are discussed. Finally, the land use scenario in 2030 is predicted, and the base flow and base flow non-point source pollution load under future land use scenarios are analyzed. The main research results of the changes in source pollution load are as follows:
(1) This paper studies the characteristics of non-point source pollution in the Huanglei River Basin. The spatial and temporal distribution characteristics of non-point source pollutants in the watershed are as follows: In terms of time, from the perspective of inter-annual changes, the loss of TN and TP pollution load from 2016 to 2018 shows a trend of increasing year by year. From the perspective of seasonal changes in the year, summer (June-August) TN and TP have the largest loss of non-point source pollution load. The multi-year average ratios of TN and TP output load to the total annual output load are 79.31% and 90.12% respectively. From the perspective of changes in the year, within the year The distribution is characterized by high flood season (rainy season) and low non-flood season (non-rainy season). The output load reaches the maximum in August, and the three-year average ratio of TN and TP output load to the total output load of the year is 65.91% respectively. , 67.83%; spatially, the multi-year average TN and TP output load of the river basin is low in the northeast and high in the southeast. The TN and TP load output intensity of the No. 13 sub-basin is the highest, and the TN and TP load of the No. 2 sub-basin are the highest. TP load output intensity is the lowest; among all land use types, the output intensity and output of TN and TP load of cultivated land are the highest.
(2) In this paper, the characteristics of base-flow non-point source pollution in the Huanglei River Basin are studied. The base flow non-point source pollution of the basin shows significant temporal and spatial distribution characteristics. In terms of time, from the perspective of inter-annual changes, the base flow index and the contribution rate of base flow to the total runoff TN and TP pollution load from 2016 to 2018 It shows a decreasing trend year by year. From the perspective of changes during the year, the multi-year average of the base flow index, base flow TN, TP load contribution rate of each month exceeds 60%. The base flow index, base flow TN, TP load in August The contribution rate was the lowest, 63.22%, 65.50%, and 67.46%, respectively, and the highest in January, all contribution rates reached 98.44%; spatially, the base flow index, base flow TN, TP load contribution rate space during the flood season and the non-flood season The distribution characteristics are basically the same, showing the characteristics of high in the east and low in the west. In the flood season, the base flow index, base flow TN, and TP of the No. 14 sub-basin have the largest contribution rates, and the base flow index, base flow TN, TP of the No. 6 sub-basin The load contribution rate is the smallest. In terms of spatial scale effect, from the small watershed at the source to the outlet of the watershed, the base flow and the non-point source pollution load of the base flow increased significantly, and the contribution rate of the base flow index and the non-point source pollution load of the base flow generally increased. As the scale increases, these values also decrease, indicating that as the watershed area expands, the impact of precipitation on base flow and base flow non-point source pollutants is continuously decreasing. At the same time, it is found that land use distribution and tributary input are base flow. And an important reason for the spatial scale effect of base-flow non-point source pollution.
(3) This paper studies the characteristics of base-flow non-point source pollution under future land use scenarios. The FLUS model is used to predict future land use changes. Based on the existing data in the study area, the 2030 land use scenario under natural development is simulated. Under the natural development of the land use scenario in 2030, for the entire watershed, the base flow index of the Huanglei River Basin and the base flow TN and TP load contribution rates did not change significantly, but in the upstream source basin and downstream alluvial plain areas, The river base flow index and base flow TN, TP load contribution rate have a certain degree of reduction.