延安市土地生态风险时空格局演变研究

段艺芳, 任志远, 周晓, 孙艺杰

Spatio-temporal variation in the land ecological risk of Yan’an City

Yifang DUAN, Zhiyuan REN, Xiao ZHOU, Yijie SUN

图2 不同时期植被覆盖度空间分布

Fig.2 Spatial distribution of vegetation coverage in different period