Ecological Risk Assessment of Gansu Section of Weihe River Basin Based on Landscape Pattern

In order to reveal impact of landscape on ecological risk in Gansu section of Weihe River Basin in recent 16 years, taking four TM remote sensing images in 2005, 2010, 2015 and 2020 as data sources, a landscape ecological risk assessment model was constructed and research on landscape ecological risk assessment and its temporal and spatial differentiation in Weihe River Basin were carried out．Results showed that, from 2005 to 2020, landscape types in study area had changed greatly, and human factors had a great interference on landscape types．From 2005 to 2020, landscape fragmentation, separation and interference in Gansu section of Weihe River Basin showed an increasing trend except for construction land, and landscape fractal dimension showed a decreasing trend except for construction land．From 2005 to 2020, spatial distribution of landscape ecological risk in Gansu section of Weihe River Basin showed a significant positive correlation．Gansu section of Weihe River Basin was dominated by ideal and good ecological risk areas, accounting for more than 62% of basin area．The poor ecological risk areas were mainly distributed in Anding District of Dingxi．On the whole, ecological risk in study area showed a stable trend．