塔里木河流域是我国生态较为脆弱的地区,过去几十年不合理的开发,导致植被覆盖遭到严重破坏。2001年以后,随着塔里木河流域近期综合治理项目等系列生态工程的实施,流域环境得到初步改善,植被覆盖日益好转。利用20012013年逐旬MODIS /NDVI数据和气象数据,通过分离气候变化对塔里木河流域植被覆盖的影响,对气候变化和人类活动对植被覆盖变化的相对作用进行定量分析。研究表明: ① 20012013年塔里木河流域植被覆盖总体呈增长趋势;植被覆盖呈改善趋势的区域占流域总面积的28.02%,呈退化趋势的区域占10.99%,其他区域则基本不变。②采用相关分析与残差法分析了气候变化和人类活动对植被覆盖变化的影响,结果表明植被覆盖变化与气候因子显著相关;人类活动对植被覆盖变化起积极作用的面积占流域总面积的61.8%,起消极作用的占38.2%。③通过对植被覆盖变化驱动因素进行相对作用分析,可以得出在植被改善区和植被退化区,人类活动的作用相对于气候因素更大,是植被覆盖变化的主要驱动因素。
英文摘要:
The Tarim River Basin is an area with relatively fragile ecological environment in China. Over the past few decades, the irrational exploitation caused the severe damage of vegetation. After 2001, the ecological environment in the river basin was improved,and the vegetation was regenerated with the implementation ofRecent Comprehensive Management Project in the Tarim River Basin. Under the premise that the main driving factors of vegetation variation were climate change and human activities, the ten-day MODIS /NDVI data and meteorological data during the period of 2001 - 2013 were used in this study so as to quantitatively analyze the effects of human activities on the change of vegetation coverage and the relative effects of climate change and human activities. The results are as follows: ① Vegetation in the Tarim River Basin was holistically improved. The areas with improved and degenerated vegetation accounted for 28.02% and 10.99% of the total area of the basin respectively,and the vegetation variation in other zones was not obvious; ② By correlation analysis and residual method, it was found that the vegetation change was significantly correlated with climatic factors,and the areas where human activities had a positive or negative effect on the vegetation change accounted for 61.8% and 38.2% of the total area of the basin; ③ The analyzed results revealed that the effects of human activities on the vegetation improvement or degeneration were more significant than those of climate change.