Li Chenrui, Yang Xin, Chen Yang, Zhou Xingyu, Li Sijin, Cui Xujia, Tang Guoan
School of Geography, Nanjing Normal University, Nanjing, 210023, China; Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China; School of Geography, Taiyuan Normal University, Jinzhong, 030619, China.
School of Geography, Nanjing Normal University, Nanjing, 210023, China; Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China.
J Environ Manage. 2025 Jan;373:123940. doi: 10.1016/j.jenvman.2024.123940. Epub 2024 Dec 31.
Despite being an essential component of gully systems, discontinuous gullies have received less attention for their complex formation mechanisms and often overlooked sediment yield processes. Factorial analysis helps elucidate gullying processes, but relevant studies on discontinuous gullies are currently lacking, especially at large scales. Spoon gullies, characterized by fat heads and thin tails, are a typical type of discontinuous hillslope gully found extensively on the Loess Plateau of China. Based on an inventory of 4077 spoon gullies and 13 geo-environmental factors, variations in factor dominance influencing the gully erosion were explored within a global-local framework, using Geodetector, geographically weighted regression, and spatially constrained multivariate clustering. Among individual factors, continuous gully density explained 41.6% of the spatial distribution of spoon gullies, followed by normalized difference vegetation index (NDVI), soil characteristics, and precipitation, ranging from 12.0% to 18.6%, while land use and topography exerted a negligible effect. The interaction of two factors showed a nonlinear enhancement in explanatory power, reaching 77.1%, 71.8%, and 69.7% when combining continuous gully density with loess thickness, precipitation, and NDVI, respectively. Moreover, except for generally negative regression coefficients of NDVI, other factors showed positive and negative values, indicating significant spatial variability in their effects on spoon gullies. Seven spoon gully clusters were thereby identified, each dominated by an evident factor among continuous gully density, precipitation, loess thickness, and soil texture. A spoon gully susceptibility map comprising five levels was further produced under a model accuracy of 85.8%, suggesting reliable performance in predicting gully occurrence. Overall, the influence of factors on spoon gully development exhibit remarkable complexities, mainly depending on spatial variation in the intricate interactions among factors and their scale-dependent behaviors. This study provides new insights into the spatial heterogeneity of discontinuous gullies at a regional scale and offers implications for developing targeted strategies against gully erosion.
尽管间断性冲沟是沟壑系统的重要组成部分，但因其复杂的形成机制以及常被忽视的产沙过程，受到的关注较少。因子分析有助于阐明沟壑发育过程，但目前缺乏关于间断性冲沟的相关研究，尤其是在大尺度上。勺状冲沟头部宽、尾部窄，是中国黄土高原广泛分布的一种典型间断性坡面冲沟。基于4077条勺状冲沟的清单和13个地质环境因素，利用地理探测器、地理加权回归和空间约束多元聚类，在全球-局部框架内探讨了影响冲沟侵蚀的因子优势度变化。在各个因素中，连续冲沟密度解释了勺状冲沟空间分布的41.6%，其次是归一化植被指数（NDVI）、土壤特性和降水量，解释率在12.0%至18.6%之间，而土地利用和地形的影响可忽略不计。两个因素的相互作用显示出解释力的非线性增强，连续冲沟密度与黄土厚度、降水量和NDVI分别组合时，解释力达到77.1%、71.8%和69.7%。此外，除NDVI的回归系数一般为负外，其他因素均有正有负，表明它们对勺状冲沟的影响存在显著的空间变异性。由此确定了7个勺状冲沟聚类，每个聚类由连续冲沟密度、降水量、黄土厚度和土壤质地中的一个明显因素主导。在模型精度为85.8%的情况下，进一步生成了包含五个级别的勺状冲沟易发性图，表明在预测冲沟发生方面具有可靠的性能。总体而言，因素对勺状冲沟发育的影响表现出显著的复杂性，主要取决于因素间复杂相互作用的空间变化及其尺度依赖行为。本研究为区域尺度上间断性冲沟的空间异质性提供了新的见解，并为制定针对性的沟壑侵蚀防治策略提供了启示。
