2000—2017年祁连山植被动态变化遥感监测

Remote Sensing Monitoring on Vegetation Dynamic Change in Qilian Mountain from 2000 to 2017

针对近期祁连山植被时空变化特征了解欠缺的问题,利用线性趋势模拟和相关性分析等方法研究了2000-2017年祁连山植被的时空变化及其影响因素。结果表明,祁连山植被NDVImax在空间上呈东多西少的分布格局。18年间祁连山植被总体呈改善趋势,其中中西部地区植被覆盖显著改善,东部局部地区退化;生长季NDVImax年均变化率为0.908×10^-3,空间上植被改善面积占总面积的40.04%。祁连山生长季植被NDVImax与降水年际变化一致,与气温存在一定的滞后性;不同季节NDVImax与气温降水的相关关系在空间上差异显著;降水是限制祁连山植被生长的主要影响因子。2015-2017年间祁连山植被覆盖有好转趋势,除受到气候变化的影响外,人工修复和改善也是植被改善的关键因子。

In view of the lack of understanding on the characteristics of the spatial and temporal changes of the vegetation in qilian mountains recently,the spatial and temporal changes of the vegetation in Qilian mountains from 2000 to 2017 and the influencing factors are studied using the methods of linear trend simulation and correlation analysis.The results show that the vegetation NDVImax of Qilian mountain presents a spatial distribution pattern of more east and less west.The vegetation of Qilian mountain appears an improvement trend during 18 years.Vegetation coverage in the central and western regions has improved significantly,and some parts of the eastern regions have been degraded.In the growth season,the annual average change rate of NDVImax is 0.908×10^-3,and the space vegetation improvement area accounts for 40.04% of the total area.The vegetation of Qilian mountain in the growing season is the same as that of precipitation,and there is a certain lag between NDVImax and temperature.The correlation between NDVImax and temperature and precipitation in different seasons is significantly different in space.Precipitation is the main factor limiting vegetation growth in Qilian mountain.From 2015 to 2017,the vegetation cover of Qilian mountain has an increasing trend.In addition to being affected by climate change,artificial restoration and improvement are also key factors affecting vegetation growth.