青藏公路工程活动对沿线植被覆盖的影响

Study of the vegetation change due to the reinforcement and rebuilding along the Qinghai-Tibet Highway

利用2000-2012年的MODIS增强植被指数(Enhanced Vegetation Index,EVI)数据,结合研究区3个气象台站长期的气象数据,分析了青藏公路沿线植被变化总体趋势,以及不同整修措施对周边植被覆盖带来的不同影响.通过实地考察,选取了16个受工程活动影响的典型路边样方,3个铁路边样方和8个远离公路铁路的自然样方,对比路边和自然样方,分析植被的自我恢复能力以及4个主要影响因子.结果表明:青藏公路沿线植被覆盖变化是在整个气候变化的背景下,叠加了工程活动的影响.植被的恢复能力与其所在路段的地形、植被覆盖度、气候条件、以及工程活动的强度均有关系,抑制植被生长的因素越多,植被恢复越慢.

Enhanced vegetation index data of MODIS from 2000 to 2012 were used to analyze the vegetation change along the Qinghai-Tibet Highway. Combined with climate data, the suppression due to reinforcement/ rebuilding projects was evaluated. Sixteen quadrates nearby highway, three quadrates nearby railway and eight original quadrates were selected to monitor. Comparing the monitored vegetation growths between quadrates nearby highway/railway and original quadrates, the self-recovery capability and its four impact factors are able to evaluate and analyze.-It is found that the influence on vegetation along the Qinghai-Tibet Highway is due to cli- mate change, superimposed with of reinforcement and rebuilding. The self-recovery ability of vegetation depends on terrain, vegetation, climate change and intensity of engineering activity.