The Response Characteristics of Xilingol Grassland to Uneven Distribution of Precipitation at Temporal and Spatial Scale

摘要

Precipitation is the most important water supply source, it has important significance on the vegetation growth, and was an important factor affecting the drought severity in Xilingol grassland. Based on 15 meteorological stations precipitation data and MODIS MOD13A3 NDVI data, Pearson correlation analysis was used to analysis the response characteristics of NDVI to precipitation at spatial and temporal scale. Results showed that from one month view, vegetation growth was the highest correlation with the precipitation of this month from May to July, but August and September were the highest correlation with the precipitation of July. Accumulated month view, the accumulated precipitation in the last three months was very important to the vegetation growth, and snowfall in the winter of previous year played an important role in May of next year. Spatially, one month view, Erenhot city and Suniteyou banner (desert steppe region) were the highest correlation with the precipitation in two months before, the others were the highest correlation with the precipitation in one month before. Accumulated month view, Erenhot city and Suniteyou banner were the highest correlation with the accumulated precipitation in the last four months, the others were the highest correlation with the accumulated precipitation in the last three months.