Seasonal Analysis of Spatial and Temporal Variations in NDVI and Its Driving Factors in Inner Mongolia During the Vegetation Growing Season (1999-2019)

Jinting Guo ^1* Weijie Liao ¹ Hasi Qimuge ¹ Youjie Xu ² Jingyuan Wang ² ； Narisu ²

• ¹ School of Life Sciences and Technology, Inner Mongolia Normal University, Huhhot, China
• ² Urat Rear Banner Management Station, Mongolian Wild Donkey National Nature Reserve, Urat015500, Inner Mongolia, China, Urat, China

Abstracts: Based on MODIS monthly composite NDVI products from 1999 to 2019 and incorporating the distinctive vegetation characteristics of Inner Mongolia, this study focused on the growing season NDVI to analyze the spatial-temporal patterns of the Normalized Difference Vegetation Index (NDVI) along this 21 yrs time span in Inner Mongolia. The investigation was conducted through a comprehensive analysis of NDVI dynamics, taking into account the region-specific ecological conditions. Additionally, the relationship between NDVI and climate change was examined using meteorological data. The findings are as follows: (1) The average NDVI distribution in Inner Mongolia exhibited significant spatial differentiation, decreasing progressively from northeast to southwest. (2) During the study period, the mean NDVI recorded during the growing season showed an increasing trend (P<0.05). Notably, summer demonstrated a highly significant increase (P<0.01), with the mean NDVI rising annually by 0.0022.(3) Over the 21-year period, temperatures during the growing season did not show notable changes across years, while precipitation exhibited a significant increasing trend. (4) The correlation between NDVI and climatic factors varied across regions and years, with precipitation emerging as the dominant factor influencing vegetation growth in Inner Mongolia. Based on these findings, it is possible to predict vegetation changes in the Inner Mongolia region by analyzing variations in precipitation patterns.