Correlation analysis of Normalized Different Vegetation Index (NDVI) difference series and climate variables in the Xilingole steppe, China from 1983 to 1999 |
| |
Authors: | Gu Zhihui Chen Jin Shi Peijun and Xu Ming |
| |
Institution: | (1) School of Architecture and Urban Planning, Shenzhen University, Shenzhen, 518060, China;(2) Key Laboratory of Environmental Change and Nature Disaster, Ministry of Education of China, College of Resource Science and Technology, Beijing Normal University, Beijing, 100875, China;(3) Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ 08901-8551, USA |
| |
Abstract: | There is a crucial need in the study of global change to understand how terrestrial ecosystems respond to the climate system.
It has been demonstrated by many researches that Normalized Different Vegetation Index (NDVI) time series from remotely sensed
data, which provide effective information of vegetation conditions on a large scale with highly temporal resolution, have
a good relation with meteorological factors. However, few of these studies have taken the cumulative property of NDVI time
series into account. In this study, NDVI difference series were proposed to replace the original NDVI time series with NDVI
difference series to reappraise the relationship between NDVI and meteorological factors. As a proxy of the vegetation growing
process, NDVI difference represents net primary productivity of vegetation at a certain time interval under an environment
controlled by certain climatic conditions and other factors. This data replacement is helpful to eliminate the cumulative
effect that exist in original NDVI time series, and thus is more appropriate to understand how climate system affects vegetation
growth in a short time scale. By using the correlation analysis method, we studied the relationship between NOAA/AVHRR ten-day
NDVI difference series and corresponding meteorological data from 1983 to 1999 from 11 meteorological stations located in
the Xilingole steppe in Inner Mongolia. The results show that: (1) meteorological factors are found to be more significantly
correlation with NDVI difference at the biomass-rising phase than that at the falling phase; (2) the relationship between
NDVI difference and climate variables varies with vegetation types and vegetation communities. In a typical steppe dominated
by Leymus chinensis, temperature has higher correlation with NDVI difference than precipitation does, and in a typical steppe dominated by Stipa krylovii, the correlation between temperature and NDVI difference is lower than that between precipitation and NDVI difference. In
a typical steppe dominated by Stipa grandis, there is no significant difference between the two correlations. Precipitation is the key factor influencing vegetation
growth in a desert steppe, and temperature has poor correlation with NDVI difference; (3) the response of NDVI difference
to precipitation is fast and almost simultaneous both in a typical steppe and desert steppe, however, mean temperature exhibits
a time-lag effect especially in the desert steppe and some typical steppe dominated by Stipa krylovii; (4) the relationship between NDVI difference and temperature is becoming stronger with global warming.
__________
Translated from Acta Phytoecologica Sinica, 2005, 29(5): 753–765 译自: 植物生态学报] |
| |
Keywords: | Normalized Different Vegetation Index (NDVI) difference series autocorrelation and non-stationarity correlation analysis precipitation and temperature |
本文献已被 SpringerLink 等数据库收录! |
|