The variability of NDVI over northwest China and its relation to temperature and precipitation
The variability of NDVI over northwest China and its relation to temperature and precipitation
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DOI：
10.1109/igarss.2003.1294413
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发表时间：
2003-07
期刊：
影响因子：
--
通讯作者：
Zhen Li;Fuli Yan;Xiangtao Fan
中科院分区：
文献类型：
--
作者：
Zhen Li;Fuli Yan;Xiangtao Fan
陆地植被通过碳循环在全球气候变化中发挥重要作用，气候变化反过来影响植被生长及其光合活性。在干旱和半干旱地区，稀疏的植被覆盖是环境的特征。因此，对植被分布及其变化进行定量的时间序列分析，可以观测年趋势，有助于找出环境变率的原因。中国西北地区存在严重的森林砍伐、水土流失、盐碱化、沙漠侵蚀等环境问题，自然条件十分脆弱。本文利用归一化植被指数NDVI （normalized difference vegetation index，简称NDVI）建立了西北地区19 a（1982—2000）植被变化的时间序列，并采用简单差值法、NDVI坡度图、生物量坡度图三种方法分析了NDVI的时间序列变化。对西北地区NDVI与气温、降水的相关性进行了分析。结果表明，西北地区NDVI与降水呈显著正相关，而气温与NDVI的相关性不强。
Land vegetation plays a major role in the global climate change through the carbon cycle, and climate change in turn affects vegetation growth and its photosynthetic activity. In arid and semi-arid areas, sparse vegetation cover characterizes environments. Thus quantitative temporal series analysis of vegetation distribution and its variations enables observing annual trends, and helps to find out the reason for environment variability. There are serious environmental problems, such as deforestation, soil erosion, salinization, and desert encroachment in northwestern China, its natural conditions are very delicate. In this paper, we build a time series of vegetation change by the NDVI (normalized difference vegetation index) covered northwest regions over 19 years (1982-2000), and analyze the time serial NDVI variability using three methods, which are simple differencing, slope map of NDVI, slope map of biomass. The correlation analysis between NDVI with the temperature and precipitation in northwestern China was carried out. The results showed that there was significant positive correlation between NDVI and precipitation but that temperature was not strongly correlated with NDVI in northwest China.