【摘要】 基于2001—2014年的MODIS数据和Landsat数据,利用温度植被干旱指数对黄土高原土壤湿度进行了反演,并应用Theil-Sen趋势和Hurst指数,通过分析土壤湿度与植被覆盖的时空变化特征及其相互关系,得到了未来不同土壤湿度情境下植被覆盖的变化特征,经过筛选和分析划分出了黄土高原生态恢复项目适宜性区域。结果表明:(1)黄土高原TVDI的Hurst指数均值为0.49,其中持续性和反持续性面积分别占42.54%,57.46%。根据TVDI未来变化特征来看,未来土壤湿度减小的区域面积占54.08%且遍布整个研究区。(2) NDVI的Hurst均值为0.52,其中持续性面积占55.01%,表明黄土高原植被覆盖持续性强于反持续性。根据NDVI未来变化特征,植被覆盖持续改善面积达46.95%,退化转为改善占6.08%,呈良好趋势。(3)生态恢复项目弱适宜区面积最大,占总面积的59.90%,其次为不适宜区,面积占25.39%;适宜区面积仅占黄土高原的13.41%,较适宜区面积仅为1.30%。(4)未来的植被恢复工程主要针对坡度较大的耕地实施退耕还林,还需要考虑对土壤水分适宜的地区进行了退草还林,而且坡度较小的较适宜区应在粮食安全的基础上进行了退耕还林和退草还林。更多还原

【Abstract】 Based on the MODIS data and Landsat data from 2001 to 2014, we have estimated the soil moisture in the Loess Plateau using temperature vegetation dryness index. The Theil-Sen method and Hurst index were used to analyze the spatiotemporal variation of soil moisture and vegetation cover as well as their interrelationship and get the different vegetation changes under different situations of soil moisture in the future. The suitability region of ecological restoration project was divided through filter and analysis in the Loess Plateau. The results showed that:(1) the average Hurst index of TVDI in the Loess Plateau was 0.49, of which the persistent and anti-persistent areas accounted for 42.54% and 57.46%, respectively; according to the characteristics of future changes of TVDI, the area of soil moisture will decrease in the future, accounting for 54.08% and distributing in the whole study area;(2) the average Hurst value of NDVI was 0.52, of which 55.01% was the sustained area, indicating that vegetation cover persistence in the Loess Plateau was stronger than that in reverse; according to the future variation characteristics of NDVI, area of vegetation cover continuing to improve accounted for 46.95%, and the area of conversion of degradation into improvement accounted for 6.08%, showing the good trend;(3) the ecological restoration project had carried out in the largest area with weak suitability, accounting for 59.9% of the total area, followed by unsuitable zones, accounting for 25.39% of the total area; the suitable area covered only 13.41% of the Loess Plateau, and the area of better suitable area was only 1.3% of the Loess Plateau;(4) the future vegetation restoration project should mainly focus on the larger sloping arable land to implement the conversion of sloping farmland into forestland, but also consider the soil water suitable areas where the grassland should be converted into the forestland, and the farmland should be converted into forestland, and the grassland should be converted into forestland in the more suitable areas with gentle slope on the basis of food security.更多还原