基于地理探测器的岷江上游地区土壤侵蚀变化

Changes in Soil Erosion in the Upper Reaches of the Minjiang River Based on Geo-Detector

为掌握岷江上游地区土壤侵蚀动态变化规律和驱动力,以修正的土壤侵蚀模型(RUSLE)为基础,实现该地区2000—2018年侵蚀定量评价,按照国家水力侵蚀分级标准将其分为6个等级,以斜率变化模型完成其动态变化规律的分析,借助地理探测器实现其变化驱动力的探索。结果表明:微度和轻度侵蚀占据全域总面积的70%以上;近20 a内,全域土壤侵蚀整体得到了有效遏制,整体发展态势相对良好;植被覆盖度、降水和高程是驱动土壤侵蚀强度空间分布格局形成和改变的主要因素,特别是植被度的驱动作用最明显;各因子间产生交互关系时,其协同作用均比单因子产生的驱动作用更明显。岷江上游地区土壤侵蚀强度分布格局差异显著,侵蚀总体得到有效遏制,植被覆盖是驱动该地区土壤侵蚀强度空间分布格局变化的主要因素。

To grasp the dynamic changes and driving forces of soil erosion in the upper reaches of the Minjiang River,based on the revised soil erosion model(RUSLE),the quantitative evaluation of soil erosion in this area from 2000 to 2018 was realized.The soil erosion was divided into 6 grades according to the national water erosion grading standard.The slope change model was used to complete the analysis of its dynamic change pattern.The geo-detector was used to realize the exploration of its driving force of change.The results show that:mild and light erosion occupied more than 70%of the total area;in the past 20 years,soil erosion in the whole region had been effectively curbed as a whole,and the overall development trend was relatively good;vegetation coverage,precipitation and elevation were the main factors driving the formation and change of the spatial distribution pattern of soil erosion intensity,especially the driving effect of vegetation degree was the most obvious;when there was an interaction between the factors,the synergy effect was more obvious than the driving effect of the single factor.There are significant differences in the distribution patterns of soil erosion intensities in the upper reaches of the Minjiang River,and the overall erosion has been effectively controlled.Vegetation coverage is the main factor driving the change in the spatial distribution pattern of soil erosion intensity in this area.