东南丘陵地区土壤侵蚀时空变化及其驱动因素——以湖南省张家界市为例

Spatial and Temporal Variability and Driving Factors of Soil Erosion in Hilly Areas of Southeast China——A Case Study of Zhangjiajie City,Hunan Province

[目的]探究东南丘陵地区土壤侵蚀状况和其空间分布,为当地的水土流失和水土保持提供理论依据。[方法]基于修正版通用流失方程(RUSLE)和地理探测器,选取中国东南丘陵地区的湖南省张家界市为研究区域,探究其土壤侵蚀的时空特征变化,并对土壤侵蚀的驱动力因子进行分析。[结果]①张家界市2000,2010,2020年平均土壤侵蚀量为1.03×10^(7),2.05×10^(7),6.74×10^(6)t/a,20a平均土壤侵蚀量呈先增加后减少趋势。②土壤侵蚀以林地侵蚀为主,其他地物类型呈不同程度的侵蚀,其中侵蚀主要集中于8°~35°坡度区域,侵蚀强度随坡度增加而增加。③研究区内土壤侵蚀由植被覆盖度、坡度、土壤属性和高程等共同作用,特别是植被覆盖度的驱动作用最明显,各因子产生交互关系时,以坡度和植被覆盖度交互时影响力最强。[结论]张家界土壤侵蚀分布具有明显的时空差异,后续需要在保障生态安全的前提下,合理开展水土保持工作。

[Objective]The status and spatial distribution of soil erosion in hilly areas were determined in order to provide a theoretical basis for limiting local soil erosion and improving soil conservation practices.[Methods]The study was conducted at Zhangjiajie City,Hunan Province in the hilly area of Southeast China.The revised universal soil loss equation(RUSLE)and geoprobe were used to to determine the spatial and temporal changes of soil erosion characteristics and to determine the driving factors of soil erosion.[Results]①Average soil erosion values at Zhangjiajie City in 2000,2010,and 2020 were 1.03×10^(7),2.05×10^(7),and 6.74×10^(6)t/a.Average soil erosion over the 20-yr study period initially increased and then decreased.②Soil erosion was dominated by forest erosion.Other land feature types showed different degrees of erosion,in which erosion was mainly concentrated in the 8°-35°slope area.Erosion intensity increased with increasing slope.③Soil erosion in the study area was affected by vegetation cover,slope,soil properties,and elevation.The most obvious factor affecting erosion was vegetation cover.The strongest interaction factor influencing erosion was found to be between slope and vegetation cover.[Conclusion]The distribution of soil erosion at Zhangjiajie City had obvious spatial and temporal differences.Soil and water conservation should be carried out reasonably on the premise of ensuring ecological security in the future.