Vegetation dynamics and factor analysis in arid and semi-arid Inner Mongolia

Arid and semi-arid regions are highly sensitive to environmental extremes, directly affecting the economic structures and development of human societies. Climate change and human activities are the major factors of vegetation changes in these regions. This study analyzes the roles of these factors of vegetation changes within forest, grassland and desert biomes across Inner Mongolia autonomous region (IM) in China and forecasts the future vegetation dynamics in this region. Based on data from 49 meteorological stations from 1961 to 2012 and the SPOT VEG Normalized Difference Vegetation Index (NDVI) satellite data from 1998 to 2012, we analyze the vegetation coverage patterns, variations and its associating dynamic responses to climate change using the methods of Maximum Value Composition, correlation analysis, fluctuation analysis and the Hurst index. The results show that NDVI patterns in IM were determined by geographical longitude and latitude. The central and eastern portion of IM encompasses a wide area with high vegetation coverage, particularly in Hulun Buir and Xilin Gol. Over the past 15 years, the NDVI has declined in the central portion of Xilin Gol, while vegetation recovery from past degradation was evident in the desert and forest regions. Our results also demonstrate that precipitation was the major driver of vegetation growth other than temperature. However, most of the vegetation in this region is likely to show strong, sustainable growth in the future.