基于SPOT-VGT NDVI的雅鲁藏布江流域植被动态变化  

Dynamic Changes in Vegetation Coverage in the Yarlung Zangbo River Basin Based on SPOT-VGT NDVI

作　　者：陈斌[1,2] 李海东[1] 曹学章[1] 唐欢欢[1,2] 

机构地区：[1]环境保护部南京环境科学研究所,江苏南京210042 [2]南京信息工程大学遥感学院,江苏南京210044

出　　处：《山地学报》2016年第2期249-256,共8页Mountain Research

基　　金：国家自然科学基金(41301611);江苏省自然科学基金(BK20130103)~~

摘　　要：基于SPOT-VGT NDVI数据集、数字高程模型(DEM)和1∶100万植被类型数据,综合运用GIS空间分析与Mann-Kendall非参数趋势检验方法,提取与分析了流域不同海拔梯度和植被类型的1999—2013年NDVI的年际和季节变化特征,探讨了高海拔大流域NDVI变化与高程、植被类型的相关性。结果表明:1.不同海拔梯度近15a的NDVI年际变化趋势与各植被类型的相似,均呈显著增长状态。<3 500 m海拔梯度NDVI变化的增长速率最大。7—9月和10—12月<4 500 m海拔梯度NDVI的生长期较长。2.阔叶林和针叶林近15 a的NDVI增长速率较大,灌草过渡、灌丛、草甸、草原、高山植被的增长速率较小。1—3月的灌丛,4—6月的草甸和草原,7—9月的阔叶林、灌草过渡、灌丛、草甸和高山植被,10—12月的阔叶林、针叶林、灌草过渡、灌丛、草原和高山植被近15 a的NDVI变化均呈显著增长趋势。3.流域NDVI变化具有显著的海拔梯度性和植被垂直地带性。<3 500 m海拔梯度的NDVI变化主要受针叶林、阔叶林的影响,>3 500 m海拔梯度的NDVI变化主要受针叶林、灌草过渡、灌丛、草甸、高山植被的影响。In this paper, the interannual and seasonal variations of mean Normalized Difference Vegetation Index （NDVI） in different altitudinal gradients and different vegetation types were extracted and analyzed from 1999 to 2013, with the help of Geographical Information System （GIS） and Mann- Kendall non-parametric test method, based on SPOT - VGT NDV! data sets, 1 ： 1 000 000 vegetation map, and Digital Elevation Model （ DEM）, there- after, the correlation between NDVI variation in different altitudinal gradients and vegetation types was discussed. The results showed that, 1 ） The interannual variation of mean NDVI in different altitudinal gradients presents ~＂sig- nificant increasing trend in the past fifteen years, the same as different vegetation types. The interannual increasing rate of NDVI variation in the altitudinal gradient less than 3 500 m is the largest. The growing season in the altitudi- nal gradients more than 4 500 m is longer than others from July to December. 2） The interannual increasing rate of mean NDVI in broad-leaved and coniferous forest is higher, while it is lower in transition of bush and grass, bush, grassland, meadow and alpine vegetation. The increasing trends of mean NDVI in different vegetation types are all significant when it points to bush from January to March, meadow and grassland from April to June, broad-leaved forest, transitions of bush and grassland, bush, meadow and alpine vegetation from July to September, broad- leaved forest, coniferous forest, transitions of bush and grassland, bush, grassland, alpine vegetation from October to December. 3） The spatial distribution and interannual variation of NDVI in the basin have the characteristics of altitudinal gradient and zonation of vertical vegetation. The variation of NDVI in the altitudinal gradient less than 3 500 m mainly affected by coniferous forest and broad-leaved forest, while it mainly affected by coniferous forest, transitions of bush and grassland, bush, meadow, alpine vegetation where altitudina

关 键 词：NDVI 海拔梯度 年际变化 季节变化 青藏高原 

分 类 号：Q948[生物学—植物学] X144[环境科学与工程—环境科学]