中国黄土高原植被覆盖变化分区研究

A Study of Vegetation Cover Change in Ecological Functional Zones of Loess Plateau in China

在遥感技术的支持下,利用2000-2011年12期的MODIS-NDVI影像数据,采用均值法与差值法、一元线性回归分析法和偏差分析法,对黄土高原不同生态功能区的植被覆盖时空变化进行了分析。结果表明:近12年,黄土高原不同区域植被覆盖变化总体呈增加趋势,但植被趋好的幅度逐渐下降。通过分区研究发现:半湿润甘陕晋黄土丘陵沟壑区(B区)和半干旱甘陕宁晋青黄土丘陵区(C区)以植被的中、高度改善为主,半干旱蒙宁陕高原区(D区)以轻微改善为主,所占比例高达59.6%。半湿润汾渭盆地区(A区)和半干旱黄河河套平原区(E区)有轻微退化现象。其中,D区和E区植被的轻微变化主要受降水和气温的影响。B区和C区由于植被保护政策的实施,植被覆盖明显增加。

This study compares the MODIS NDVI image data of 12 years from 2000 to 2011 by the technology of remote sensing and analyzes the vegetation change on different ecological functional zones in Loess Plateau through methods of mean value,difference value,unary linear regression,and deviation analysis. The results indicate that the total area of vegetation cover of all ecological functional zones in Loess Plateau was increasing in recent 12 years. However,the vegetation increasingly good rate was gradually decreased while the vegetation degradation rate was slightly increased. Comparing different zones,it could be found that： the sub-humid loess hilly and gully regions of Gansu,Shaanxi and Shanxi（ Zone B） and the semi-arid loess hilly regions of Gansu,Shaanxi,Ningxia,Shanxi and Qinghai（ Zone C） took a high or moderate degree of revegetation. The semi-arid plateau region of the Inner Mongol,Ningxia and Shaanxi（ Zone D） was mainly to the slight revegetation with a high proportion as 59. 6%. While the sub-humid regions such as Fenhe River Basin and Weihe River Basin（ Zone A） and the semi-arid plains regions of the Yellow River Loop（ Zone E） took a slight degradation. The vegetation for Zone D and Zone E was mainly influenced by the precipitation and the temperature. Under the intervention of vegetation protection policy,Zone B and Zone C had a big increase in vegetation cover.