| The Mu Us Sandy Land, one of China's four major sandy areas, has achieved a historic transformation from “sand advancing and people retreating” to “green advancing and sand retreating” in recent years, owing to global climate change and the implementation of policies such as "returning farmland to forests and grasslands". As a result, vegetation conditions in the region have significantly improved. This study takes the Mu Us Sandy Land as the research area, and, by applying remote sensing and GIS technologies, selects multiple indicators including the Normalized Difference Vegetation Index (NDVI), Fractional Vegetation Cover (FVC), and Net Primary Productivity (NPP) to monitor vegetation restoration from four aspects: spatial distribution, magnitude of change, trend of change, and stability. The results showed that:(1) From 2000 to 2020, the NDVI in the Mu Us Sandy Land increased at a rate of 0.75% per year, indicating significant vegetation restoration. (2) The spatial distribution of FVC exhibited significant variation, with vegetation coverage generally decreasing from southeast to northwest. The proportion of bare land continued to decline, while the proportion of medium- to high-vegetation coverage areas steadily increased. Over the past two decades, vegetation coverage has continuously expanded and improved markedly. (3) From 2000 to 2016, the NPP index increased significantly, with growth in the southeast being more pronounced than in the northwest, indicating a notable improvement in vegetation productivity. The trends reflected across the NDVI, FVC, and NPP indicators from 2000 to 2020 were consistent, showing that the vegetation in the Mu Us Sandy Land had been clearly and continuously recovering. |
