Laraib Sheikh, Xiong Donghong, Zhao Dongmei, Shrestha Buddhi Raj, Liu Lin, Qin Xiaomin, Xie Xiao, Rai Dil Kumar, Zhang Wenduo
State Key Laboratory of Mountain Hazards and Engineering Resilience, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610299, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Environ Monit Assess. 2024 Jul 13;196(8):731. doi: 10.1007/s10661-024-12889-4.
Gully erosion is a serious global environmental problem associated with land degradation and ecosystem security. Examining the influencing factors of gullies and determining susceptibility hold significance in environmental sustainability. The study evaluates the spatial distribution, influencing factors, and susceptibility of gullies in the Sunshui River Basin in Sichuan Province, Southwest China. The frequency ratio method supported by satellite images and the gully inventory dataset (1614 gully head points) with different influencing factors were applied to assess the distribution and susceptibility of gullies. Additionally, gully head points were grouped into a training set (70%, 1130 points) and a test set (30%, 484 points). Spatial distribution results indicated that most gullies are located in the middle and upper part of the basin, characterized by moderate elevation (2100-3300 m), steep slopes (11.63-27.34°), abandoned farmland, and Cambisols soil, and fewer gullies are located in lower part characterized by lower elevation, gentle slopes, and low vegetation coverage. Land use and land cover influence on susceptibility is significantly greater than other factors with a prediction rate of 33.9, especially farmland abandonment, while the occurrence of gullies is also more often on southwest-orientated slopes. Gully susceptibility highlighted that the study area affected by the very low, low, moderate, high, and very high susceptibilities to these gullies covered an area of about 16%, 23%, 32%, 26%, and 3% of the total basin respectively, which indicates 61% of the study area is susceptible to gully erosion. Moderate to high susceptibility is situated in the upper and middle part, consistent with the spatial distribution of gullies in the basin, and very high susceptibility (3%) is distributed in both the lower and upper parts of the basin. These results have important implications for soil loss control, land planning, and integrated watershed management in the mountainous areas of Southwest China.
沟蚀是一个严重的全球性环境问题，与土地退化和生态系统安全相关。研究沟壑的影响因素并确定其敏感性对环境可持续性具有重要意义。本研究评估了中国西南部四川省孙水河小流域沟壑的空间分布、影响因素及敏感性。利用卫星影像支持的频率比法以及包含不同影响因素的沟壑清单数据集（1614个沟头点）来评估沟壑的分布和敏感性。此外，将沟头点分为训练集（70%，1130个点）和测试集（30%，484个点）。空间分布结果表明，大多数沟壑位于流域中上游，其特征为海拔适中（2100 - 3300米）、坡度陡峭（11.63 - 27.34°）、有弃耕地以及存在雏形土，而位于下游的沟壑较少，其特征为海拔较低、坡度平缓且植被覆盖度低。土地利用和土地覆盖对敏感性的影响显著大于其他因素，预测率为33.9，尤其是农田弃耕，同时沟壑也更常出现在西南向的斜坡上。沟壑敏感性表明，研究区域受极低、低、中、高和极高敏感性影响的沟壑面积分别约占流域总面积的16%、23%、32%、26%和3%，这表明61%的研究区域易发生沟蚀。中高敏感性区域位于流域的中上部，与流域沟壑的空间分布一致，极高敏感性区域（3%）分布在流域的上部和下部。这些结果对中国西南部山区的土壤流失控制、土地规划和流域综合管理具有重要意义。
