Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of the Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, China.
Sci Total Environ. 2021 Mar 1;758:143661. doi: 10.1016/j.scitotenv.2020.143661. Epub 2020 Nov 20.
Soil erosion is an increasingly serious eco-environmental problem and an important driver of phosphorus loss, which not only reduces soil productivity but also decreases water availability. The integration of the universal soil loss equation (USLE) and the geographic information system (GIS) technique is globally popular for erosion prediction and assessment. The Fen River basin is located in the east of the Loess Plateau and has eco-environmental problems of soil erosion and eutrophication because of excess phosphorus content. This study attempted to use the USLE model to evaluate soil erosion and the transport of the resulting particulate phosphorus in the Fen River basin under a GIS framework. The results showed that soil erosion in 15.8% of the study area exceeded 8000 t/(km·a) and was mainly distributed in the upper Fen River basin. Soil erosion was greatest in the bareland area, with an average of approximately 1.22 × 10 t/(km·a), followed by that in grassland. Soil erosion in the study area is most sensitive to the rainfall erodibility (R), followed by the soil erodibility (K), topographic factors including slope steepness (S) and slope length (L), the soil and water conservation factor (P), and the vegetation cover and management factor (C). Similar to soil erosion, the high-risk areas of particulate phosphorus transport were mainly concentrated in the upper reaches of the basin. The study also pointed out that the combined use of available data sources with the USLE model and GIS technique is a viable option to calculate soil erosion and assess the risk of particulate phosphorus transport, which could provide a scientific basis for reducing soil erosion and controlling phosphorus migration.
土壤侵蚀是一个日益严重的生态环境问题，也是磷素流失的重要驱动因素，它不仅降低了土壤生产力，还减少了水资源的可利用性。通用土壤流失方程（USLE）与地理信息系统（GIS）技术的结合，在全球范围内被广泛用于侵蚀预测和评估。汾河流域位于黄土高原东部，由于磷含量过高，存在土壤侵蚀和富营养化等生态环境问题。本研究试图在 GIS 框架下，利用 USLE 模型评估汾河流域的土壤侵蚀和由此产生的颗粒态磷的输移。结果表明，研究区 15.8%的土壤侵蚀超过 8000 t/(km·a)，主要分布在上游汾河流域。裸地的土壤侵蚀最大，平均约为 1.22×10 t/(km·a)，其次是草地。研究区土壤侵蚀对降雨可蚀性（R）最敏感，其次是土壤可蚀性（K）、地形因子（包括坡度陡峭度（S）和坡度长度（L））、水土保持因子（P）和植被覆盖与管理因子（C）。与土壤侵蚀类似，颗粒态磷输移的高风险区主要集中在流域上游。本研究还指出，结合使用现有数据源、USLE 模型和 GIS 技术是计算土壤侵蚀和评估颗粒态磷输移风险的可行选择，可为减少土壤侵蚀和控制磷迁移提供科学依据。
