Ecosystem Health Assessment of Shangqiu Section of Old Yellow River Course Basin Based on Landscape Patterns

Abstract

The Old Yellow River Course features unique hydrological structures and ecological environments, directly influencing regional biodiversity and socio-economic development. This study focuses on Shangqiu Section of Old Yellow River Course Basin and its surrounding areas. Utilizing four phases of LandsatTM remote sensing images we integrated eight landscape pattern indices with the Pressure-State-Response (PSR) model to construct an Ecosystem Health Index (EHI). This framework quantifies the evolution of ecological health over 30 years, and the dynamic changes of ecosystem health in Shangqiu Old Yellow River Basin are evaluated. Key findings include: 1) Land use changes: Cultivated land decreased cumulatively by 9.13%, while construction land expanded in a multi-nuclei diffusion pattern (+9.04%). Wetlands and forest land showed fluctuating trends, declining initially before partial recovery. 2) Landscape pattern evolution: From 1993 to 2003, fragmentation intensified (PD increased) and diversity decreased (SHDI decreased); from 2003 to 2013, artificial landscapes aggregated (CONTAG increased) and biological corridors were fragmented; from 2013 to 2023, local restoration slightly increased SHDI, but connectivity continued to degrade (CONNECT decreased). 3) Ecological health trend: EHI showed a continuous decline (1993: 0.440→2003: 0.332 →2013: 0.269→2023: 0.228), dropping from the "sub-healthy" to "sick" grade; spatially, it presented a "low in the west and high in the east" pattern, with high-health areas concentrated in wetland parks and forest belts. This study reveals the chain ecological degradation mechanism under human activity interference, providing a scientific basis for landscape optimization in Yellow River floodplain.