中文摘要：

为了探究神木县2003-2013年总体植被状况及覆盖度时空变化特征,文章利用2003,2008,2013年的MODIS/NDVI影像,计算了神木县2003,2008,2013年的植被覆盖度,从时间和空间上对神木县植被覆盖度的变化情况做出了分析。结果发现：从时间上看,神木县植被覆盖度总体上呈增长的趋势;微覆盖度类以很小的比例基本保持不变,低覆盖度类减少;中、高覆盖度类呈增长趋势;从空间上看,神木县植被覆盖度呈现东南高西北低的态势;2003-2008年,东部的中植被覆盖度类面积向西扩张,使地势较平缓的西部的低覆盖度类减少;2008-2013年,东部、南部出现高覆盖度类,且基本沿河谷和山脊分布,中覆盖度类继续向西部扩张,使低覆盖度类进一步减少。

英文摘要：

To explore the general vegetation condition of Shenmu County in Shaanxi Province and its vegetation frac-tion change in time and space, the MODIS images of 2003, 2008 and 2013 are used to calculate the vegetation fraction of Shenmu County in 2003, 2008 and 2013 using GIS, and the change of the vegetation fraction of Shenmu County is analyzed temporally and spatially. The result shows, that temporally, the vegetation fraction of Shenmu County general-ly increases from 2003 to 2013. The class of Micro-vegetation-fraction keeps invariant basically with a small ratio. The class of low-vegetation-fraction reduces. The class of mid and high-vegetation-fraction shows a trend of increase. Spa-tially, the vegetation fraction of Shenmu County shows a trend of highness in the southeast and low in the northwest. From 2003 to 2008, westward expansion, the class of mid-vegetation-fraction in the southeast makes the class of low-vegetation-fraction decrease in the northwest part of Shenmu where the terrain is flat. From 2008 to 2013, the class of high-vegetation-fraction appears in the east and south of Shenmu, and it mainly distributes along the valley and the ridge, and class of mid-vegetation-fraction continues to expand westward, making the class of low-vegetation-fraction decrease further.