基于遥感的植被年际变化及其与气候关系研究进展

Advance in the Inter-annual Variability of Vegetation and Its Relation to Climate Based on Remote Sensing

植被具有明显的年际变化和季节变化特点,对植被的动态监测可以从一定程度上反映气候变化的趋势,因此监测植被动态变化以及分析这种变化与气候的关系已经成为全球变化研究的一个重要领域。随着遥感卫星获得长时间系列逐日观测数据,许多国际组织和机构制定了全球卫星数据接收、处理和生成数据集计划,所产生的标准数据集则极大地促进了该项研究。大量研究在全球尺度、洲际尺度(北美洲和欧亚大陆)以及区域尺度上广泛开展。在阅读国内外大量文献的基础上,比较分析了常用于植被监测的卫星传感器和主要数据集,汇总了植被年际变化及其与气候关系研究的主要研究方法和研究结果。结果表明近20年来全球植被活动明显增强,表现为北半球普遍存在增加的趋势,南半球干旱半干旱区出现降低的植被光合作用,但这些变化因空间位置不同和研究尺度不一样体现出不同的动态变化特征。气温和降水是影响植被变化的最主要的因素。

Climate indicators suggest a warming of the Earth. Since vegetation elicits seasonal dynamics and annual changes, the monitoring of vegetation change is an important activity to study global climatic change. The daily temporal resolution and global coverage of some satellite sensors make it possible to monitor vegetation at different spatial and temporal scales globally. The pre-processing of remote sensing （ RS ） data affects monitoring results directly, so a lot of international organizations perform global satellite data acquisition to receive, process, and create data sets, which strongly supports this work. Indications exist as well that an increase in global and specifically boreal vegetation activity occurs. The middle and high latitude region of the Northern Hemisphere show a widely increasing vegetation activity while arid and semi-arid regions elicit a decrease in vegetation photosynthesis in the Southern Hemisphere. It is suggested that precipitation and temperature are the primary drivers for inter-annual vegetation changes. Vegetation cover changes are also highly related to ecosystems susceptible to global climate change.