Ecological land evolution index: An improved approach to characterize the process of ecological land evolution

Background Ecological land evolution is essential in shaping regional landscape patterns, influencing ecosystem processes, and altering ecosystem functions. However, existing indices inadequately quantify both ecological land degradation and restoration patterns, particularly regarding patch-scale dynamics related to connectivity and fragmentation. This study aimed to propose the Ecological Land Evolution Index (ELEI), a novel metric designed to comprehensively assess the spatiotemporal intricacies of ecological land evolution at the patch level. By integrating spatial proximity and ecological connectivity, ELEI offers a more refined and holistic evaluation compared to traditional landscape indices, thereby enhancing our comprehension of these dynamic evolution processes. Results Utilizing four temporal snapshots (1990, 2000, 2010, and 2020) of land use raster data from the urban agglomeration in the middle reaches of the Yangtze River (UAMRYR) in China, we applied ELEI to assess patterns of ecological land restoration(ELR) and degradation(ELD). The results demonstrate significant spatiotemporal heterogeneity in ecological land evolution. Cities such as YCH, HY, and JJ showed large-scale ecological restoration, primarily driven by the expansion of connecting and infilling patches. In contrast, highly urbanized areas like WH and CS exhibited severe fragmentation, particularly in the form of fragmented and enclosed patches. The data also revealed significant shifts in ELR and ELD distributions, with fragmentation intensifying from 2000 to 2010, followed by signs of reversal in the subsequent decade due to large-scale restoration initiatives. Compared to other indices, ELEI provides a more in-depth and comprehensive understanding of ecological land dynamics in rapidly urbanizing areas, identifying regions where restoration efforts have succeeded and where degradation continues. Conclusions This studying demonstrated ELEI’s effectiveness in identifying key areas of restoration and degradation, offering crucial insights for policymakers striving to balance economic development and ecological conservation. Additionally, the use of ELEI variants (Mean ELEI (MELEI) and Area-Weighted Mean ELEI (AWMELEI)) highlights their value in tracking spatial connectivity and degradation over time, providing a valuable tool for regional conservation planning and landscape management.