Influence of Climate And Grazing on NDVI in a Typical Steppe Region in Inner Mongolia, China

Abstract

Based on temperature and precipitation data from 15 meteorological stations and data on livestock populations, we digitized spatial data related to climate aridity and livestock density in Xilingol Leauge, a typical steppe region of northern China, and analyzed the relationships among vegetation cover change (as measured by NDVI), aridity and grazing activity. The results show that: (1) the spatial pattern of the relationship between NDVI and the de Martonne aridity index (IdM) was positive in most parts of Xilingol League; (2) livestock density increased from northwest to southeast, with 53.2% of the study area having livestock density of 40-80 standard sheep units/km2; (3) there was a binomial regression relationship between NDVI and livestock density, with higher livestock density that was concentrated in areas where the NDVI value ranged from 0.46 to 0.62; (4) there was complex linear correlation among NDVI, IdM, and livestock density; (5) partial correlation analysis revealed a significant negative correlation between livestock density and NDVI, and a positive correlation between IdM and NDVI, and the influence of aridity on NDVI was considerably greater than that of livestock density.