Spatiotemporal Heterogeneity and Key Driving Factors of Ecological Land Fragmentation in Guanzhong Plain Urban Agglomeration, China

Due to the multiple impacts of global climate change and anthropogenic disturbances, regional ecological landscapes have been developing towards fragmentation. How to quantitatively measure regional ecological landscape fragmentation and identify its key drivers is an important foundation for regional biodiversity conservation and ecosystem restoration. Taking the Guanzhong Plain Urban Agglomeration (GPUA), China as the research object, this paper proposes a comprehensive framework that integrates landscape pattern index, principal component analysis, random forest (RF) and other methods to quantitatively analyze the spatial and temporal evolution of ecological landscape fragmentation and its driving factors. The results show that: 1) cropland, forestland and grassland showed significant spatial differentiation in the landscape pattern index, and the change of their mean values indicated that cropland and forestland show a trend of ‘little decrease-continuous increase’. Spatially, the northwestern and southeastern regions showed significant fragmentation and prominent spatial heterogeneity. 2) From 2010 to 2020, the landscape fragmentation of cropland and forestland increased by 71% and 20%, respectively, while that of grassland decreased by 33%, indicating that the degree of landscape fragmentation of cropland changed more drastically than that of other ecological land. 3) It was found that slope was the most important factor affecting landscape fragmentation of ecological land. In addition, road density had a significant effect on landscape fragmentation of cropland and forestland, but the min-distance between patches and the county center had an important effect on landscape fragmentation of grassland. This study can provide theoretical references for urban agglomeration planning and sustainable landscape management on a regional scale.