典型冰冻圈地区植被变化对人类活动的响应研究 ——以祁连山为例

在全球气候变化、种植业结构调整等背景下，亟需对祁连山区的植被展开长期有效的监测和持续研究。基于2000-2017年分辨率为250 m的MODIS数据，采用Mann-Kendall时间序列非参数估计模型、相关分析等方法，分析了祁连山区生长季NDVI与植被盖度的时空变化特征及其与气候因子的相关性，并从正反两方面就人类活动对对植被的影响做了讨论，得出结论如下：（1）从东向西祁连山年平均NDVI整体上逐渐减小，NDVI随海拔升高呈先增大后减小的特征，NDVI最大的区域分布在海拔2 700~2 900 m的范围内；（2）祁连山区域内NDVI显著减小的区域占祁连山总面积的0.6%，而显著增加的区域占总面积的33.6%，植被呈现出整体向好，局部退化的趋势；（3）2000-2017年，林地、草地和其他土地利用区的植被盖度分别以0.0029、0.0026和0.0004的速率增加，工矿用地的覆盖度以0.0112的速率在减少，反映出工矿业开发活动是造成植被盖度下降的主要因子；（4）植树造林区植被NDVI以0.0455的速度增加，而工程实施和矿产开发区NDVI以0.0125速度降低，表明人类活动是导致植被群落变化的主要因素之一。

Research on the response of vegetation change to human activities in typical cryosphere areas: taking the Qilian Mountains as an example

under the background of ecological destruction, global climate change and the adjustment of planting structure in the Qilian Mountains, it is urgent to carry out long-term an effective monitoring and continuous research on the vegetation. Based on the resolution of 250 m of MODIS data in 2000-2017 and combining with climate data, using the Mann-Kendall non-parametric estimation model, as well as correlation analysis, the spatial and temporal variation characteristics of normalized difference vegetable index (NDVI) and vegetation in growing season of the Qilian Mountains and their correlation with climatic factors are analyzed. Also the impacts of human activities on vegetation are explored from both positive and negative aspects. The following conclusions can be drawn:(1) the average annual NDVI in the Qilian Mountains decreases gradually from east to west. NDVI first increase, and then decreases with the elevation rise; the maximum NDVI ranges between 2 700 and 2 900; (2) In the Qilian Mountains there is 0.6% of the total area having NDVI significantly decreasing and 33.6% of the total area having NDVI significantly increasing; the vegetation is showing a trend of overall improvement and local degradation; (3) The coverage of forest land, grassland and other land using area has increased by 0.0029, 0.0026 and 0.0004, respectively; the coverage of industrial and mining land has decreased by 0.0112, which reflect that the development of industry and mining has caused vegetation coverage decline; (4) The NDVI of planting and reforestation area have increased at the rate of 0.0455, while that of engineering implementation and mineral development area have decreased at the rate of 0.0125, indicating that human activities are one of the main factors leading to the change of vegetation community.