Spatial-temporal analysis of ecological risks in Northwest Sichuan Plateau based on landscape pattern

Based on the land use data of 2010, 2015 and 2020, and taking Northwestern Sichuan Plateau as the study area, the ecological risk assessment system was constructed from the perspective of landscape pattern, and the spatial-temporal characteristics of ecological risk were put under examination. The results show that: (1)During the study period, the area of grassland and woodland changed significantly, the proportion of grassland area decreased from 60.68% in 2010 to 59.03% in 2020, and the proportion of woodland area increased from 30.62% in 2010 to 31.94% in 2020. (2)The ecological risk of the northwest Sichuan Plateau as a whole showed the spatial distribution characteristics of high in the western, northeastern and southeastern regions and low in the eastern region; (3) From 2010 to 2020, the regional ecological risk level was converted from high to low by 72.834×10 ⁵hm ², while the area changing from low to high was 66.845×10 ⁵hm ², showing that the overall ecological risk was reduced.