Spatiotemporal patterns and driving factors of landscape ecological risk in the major sugarcane-producing region: an assessment from Guangxi, China (2000–2023)

Rapid urbanization and intensive human activities substantially reshape land use patterns and ecosystem functions across ecologically fragile regions, thereby inducing widespread landscape ecological risks (LER). Landscape ecological risk assessment is essential for effective ecological governance and sustainable land management in vulnerable karst agricultural areas. As a core sugarcane-producing region located in the typical karst terrain of southern China, Guangxi sustains national sugar security, while its spatiotemporal dynamics of landscape ecological risks remain poorly understood. Based on land use datasets spanning 2000 to 2023, a landscape ecological risk assessment framework integrating multiple landscape metrics and the Geodetector model was applied to reveal grid- and county-level LER variations and their underlying driving mechanisms. The results show that (1) The study area experienced drastic land use changes, with continuous forestland growth, fragmented cultivated land loss, and a 102.89% built-up land expansion. Noticeable land use conflicts existed among ecological restoration, farmland protection and urban sprawl. Regional ecological risk stably presented a spatial pattern of low in the north and high in the south, fluctuating upward before a persistent decline after 2015, which indicated continuous ecological improvement. (2) Topographic slope dominated the spatial differentiation of ecological risk. Nighttime light-indexed urbanization showed increasing explanatory capacity for risk changes, while the expansion of sugarcane cultivation scale has a relatively limited impact. (3) Agricultural cultivation and terrain factors exhibited significant nonlinear interactive enhancement. Sloping farmland was identified as the key ecologically sensitive area requiring targeted governance. The results demonstrate that landscape ecological risk variations are jointly driven by natural constraints and urban anthropogenic disturbances, rather than single agricultural activities. This study provides scientific support for coordinating crop industry development, cultivated land conservation and ecological security in global karst regions.