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3 不同时期降水距平百分比指数空间分布

Fig.3 Spatial distribution of percentage of precipitation anomaly in different period