Abstract:

In the Horqin Sandy Land,as an ecologically fragile area in northern China,the change of vegetation cover is affected by both climate change and human activities.With the NDVI data,precipitation records,and remote sensing interpretation results of land use from 2000 to 2020,using models such as gridded analysis,correlation analysis,and the land use transfer matrix,we quantitatively evaluates the driving mechanism of precipitation and land use changes on vegetation cover.The results show that:1)The vegetation cover index in the study area shows an upward trend(with a growth rate of 0.007 5 a^-1),and spatially,it presents a pattern where the Xiliao River Basin in the southeast and central parts is high,the north and south sides are relatively low,and the southwest is the lowest;2)There is a positive correlation between precipitation and NDVI with the correlation coefficient of 0.74,and the precipitation shows a wave-like increase over time;3)In the change of land use,the area of farmland remains basically stable,the area of grasses increases slightly,the areas of water bodies and sandy wasteland decrease significantly,the construction area increases remarkably,and the area of forest land accounts for the smallest proportion but has the largest growth rate;4)Among all land use types in 2020,the NDVI value of farmland is the largest,and that of sandy wasteland is the smallest.

Key words: gridding, Horqin Sandy Land, vegetation cover, analysis