This paper presents the vegetation change trends and their causes in the Inner Mongolian Autonomous Region, China from 1982 to 2006. We used National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data to determine the vegetation change trends based on regression model by fitting simple linear regression through the time series of the integrated Normalized Difference Vegetation Index (NDVI) in the growing season for each pixel and calculating the slopes. We also explored the relationship between vegetation change trends and climatic and anthropogenic factors. This paper indicated that a large portion of the study area (17%) had experienced a significant vegetation increase at the 0.05 level from 1982 to 2006. The significant vegetation increase showed no positive link with precipitation and was mainly caused by human activities. In or to the south of Horqin Sandy Land, in the Hetao Plain, and at the northern foothills of the YinshanMountain, the significant NDVI increase trends were mainly caused by the increase of the millet yield per unit of cropland. In the east of Ordos Plateau, the significant NDVI increase trends were mainly determined by the fencing and planting of grasses and trees on grassland. 1. Introduction Desertification is one of the most serious regional environmental issues [1]. China is one of the major countries facing this problem in the world. The total area of desertification-prone land was approximately 2.62 million km2, occupying 27.3% of the total area of China [2]. The Inner Mongolian Autonomous Region, located in the north of China, is a typical agriculture-grazing transitional zone that has been seriously affected by desertification and has suffered from severe wind erosion and a high frequency of dust storms [3]. Thus, it is very important to determine the vegetation change trends for combating the desertification in this area. With the accumulation of remotely sensed images over the past three decades, research on desertification based on monitoring vegetation change has been conducted from national to regional scales [4–9]. Fang et al. [4] and Piao et al. [5] reported that the vegetation in arid and semiarid areas of China increased significantly according to the analyses of NOAA/AVHRR data from 1982 to 1999. These results suggested a reversal of the desertification processes in these regions. This research attributed the major cause of the vegetation increase to precipitation change. According to the research above, human activity was only responsible for a minor part of the
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