Effects of landscape patterns and their changes on ecosystem health under different topographic gradients: A case study of the Miaoling Mountains in southern China

Ecosystem health is an essential characterization of landscape pattern ecological effects, and refined analysis of the variability of landscape pattern changes on ecosystem health in mountainous areas is of great significance for the synergistic development of the mountainous Man-Earth systems. This study constructed a research framework for the ecological effects of landscape patterns based on the theory of landscape ecology and topographic gradient. Taking the Miaoling Mountains in China as an example, used spatial analysis techniques to analyze the process of landscape pattern changes from 2000 to 2020 and detected the response of ecosystem health to the changes in the landscape pattern by using rank correlation analysis. The study showed that: (1) The landscape pattern of the study area changed significantly during the study period, especially in the geographically disadvantaged areas, mainly showing an expansion of the landscape scale of the forestland and a shift of the landscape dominance of the farmland to the gently sloping lowland areas. (2) The ecosystem was at an average health level (mean ecosystem health index (EHI) = 0.58), and the EHI showed a “V” shape dynamic since 2000. (3) The changes in landscape patterns significantly impacted ecosystem health, and the effect varies considerably across topographic gradients, with the landscape shape index (LSI) and Shannon diversity index (SHDI) being the main factors influencing ecosystem health. This study emphasizes the importance of implementing regional and systemic landscape management strategies in the Miaoling Mountains according to local conditions and suggests four rational strategies, including zoning controls around the forestland and farmland. The study's results provide a valuable reference for defining key conservation areas and control indicators for regional ecological restoration in the Miaoling Mountains and for landscape management in mountainous regions worldwide.