荒漠化是中国北方干旱、半干旱地区面临的主要生态环境问题。从植被特征着手，关注其年际动态变化特征，已经成为国内外荒漠化评价的发展趋势。选取遥感反演的高时间分辨率的植被降水利用率作为评价指标，利用时间序列分析方法，评价了内蒙古自治区1999-2009 年的荒漠化发展态势，并对荒漠化逆转问题进行了初步讨论。结果表明：内蒙古自治区11 年来生态环境总体趋于改善，荒漠化发展态势并不明显。其中，鄂尔多斯高原的东部至大青山南麓、大兴安岭及燕山北部余脉是内蒙古自治区生态环境改善最为明显的地区，反映出该区的植被保护政策发挥了积极的作用；荒漠化土地空间分异特征表明，降水因子和植被恢复有着密切的联系，300mm以上降水量的地区，其植被恢复能力要明显大于降水稀少的地区；干旱、极干旱地区的荒漠界限极不稳定，对荒漠化是否逆转的判断必须在特定的时间尺度，结合当年的气候条件进行综合分析。
Desertification is one of the serious threats to the environment in arid and semi-arid northern China. In order to understand inter-annual vegetation dynamics, vegetation indicators have been widely used in desertification assessment. In this study, rain use efficiency (RUE) derived from hyper-temporal remote sensing images has been used for desertification assessment. Based on time-series analysis, this study focused on how the desertification developed in Inner Mongolia and how the desertification reversed in the extremely arid environment. Results showed that during the past 11 years, there was no significant desertification development in Inner Mongolia. Parts of area showed a significant increase trend of RUE, especially in the eastern part of Ordos Plateau and southern Daqing Mountain, as well as the region from the Greater Hinggan Mountains to northern Yanshan Mountains. It is indicated that the ecological conditions in these areas have tended to be much better than before. The reason may be that the vegetation protection policies adopted in northern China have exerted a positive effect on the local environment. The results also showed that there was a significant relationship between rainfall and vegetation restoration, areas with more precipitation tend to be more easily restored, especially in the areas with more 300 mm precipitation. In addition, the research on desertification reversion showed that the desert edge region in western Inner Mongolia have changed intensively, and desertification reverse assessment needs to be further examined.
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