黑河流域植被覆盖程度变化研究

Research on Dynamic Changes of the Vegetation Coverage Levels in Heihe River Basin

基于长时间序列SPOT VGT-NDVI影像数据,利用均值法、最大值合成法、最小二乘法、NDVI变化度模型等方法,研究黑河流域1999—2010年植被覆盖程度的动态变化规律。结果表明:研究时段内流域的植被覆盖程度呈逐步改善趋势,改善面积百分比为26.65%,其高度改善区域面积为71.79 km2,几乎全部集中在黑河中游地区;但流域植被覆盖水平整体较差,从东南向西北逐步呈荒漠化态势变化;研究发现部分地区植被仍有退化现象。

This paper analyses the regulation of the vegetation coverage dynamic change of Heihe River Basin from 1999 to 2010 by taking the mean method, the maximum synthesis, least squares method and the model of ND- VI change degree, etc. , based on the SPOT VGT-NDVI image data. Results indicate that： the vegetation coverage in Heihe River Basin has improved in these nearly 12 years, the improved ratio is 26.65% , the area of the highly improved region is 71.79 km2, almost all of which concentrated in the middle region ; the vegetation coverage in Heihe River Basin is not high overall, which gradually changes with the trend of desertification from the southeast to the northwest ; and it＇ s found that there are still vegetation coverage degenerations in some parts of the basin.