MODIS-based remote-sensing monitoring of the spatiotemporal patterns of China's grassland vegetation growth

Abstract

China has abundant grassland resources (approximately 400 million ha of natural grasslands), which account for 41.7% of China's total area. Grasslands are an important base for boosting the development of China's livestock husbandry economy and maintaining China's ecological security. Using Moderate Resolution Imaging Spectroradiometer (MODIS) remotely sensed data, this study developed a grassland vegetation growth index that ranked the magnitude of grassland vegetation growth indices across a wide variety of field experiments. This study applied the grassland vegetation growth index to conduct remote-sensing monitoring of the spatiotemporal status of China's grassland vegetation growth in 2008. We found that the vegetation growth of China's grassland was classified as ‘good’ in 2008. The areas of grassland with desirable vegetation growth accounted for 38.47% of China's monitored grassland areas, and the areas with less desirable vegetation growth accounted for 22.85%. Additionally, the good vegetation growth was stable within each 10 day study period in 2008. The vegetation growth reached a balance in early June. After early September, the proportion of grasslands with desirable vegetation growth declined, and the proportion of grasslands with balanced and less desirable growth increased. The regions with less desirable vegetation growth mainly included the middle and eastern regions of Inner Mongolia, the northern region of Xinjiang, and most parts of Heilongjiang. The regions with desirable vegetation growth were mainly distributed in the north of Tibet, the southwest of Qinghai, the west of Inner Mongolia, Gansu, Ningxia, Shanxi, and the northwest of Liaoning. The remote-sensing monitoring of the spatiotemporal patterns of China's grassland vegetation growth in the present study revealed the overall vegetation growth status of China's grassland on a broad scale. These findings could provide a helpful scientific basis for understanding China's grassland vegetation conditions and the management and regulation of grassland livestock husbandry.

Acknowledgements

This study was supported by the National Natural Science Foundation of China (40701055), the Hi-Tech Research and Development Programme of China (863 programme) (2006AA10Z242), the Special Basic Research Fund for Central Public Scientific Research Institutes (2012INRRP-20), the Project for Agricultural Information Early Warning of Monitoring and Evaluation of Remote Sensing, and the Grassland Resources and Ecological Monitoring Project. We wish to acknowledge the assistance of the Department of Development and Planning and Monitoring and the Grassland Monitoring and Supervision Center, Ministry of Agriculture, PRC.