应用生态学报2017,Vol.28Issue(8):2413-2422,10.DOI:10.13287/j.1001-9332.201708.005
中国东北多年冻土区植被生长季NDVI时空变化及其对气候变化的响应
Spatiotemporal variations of growing-season NDVI and response to climate change in permafrost zone of Northeast China
摘要
Abstract
Permafrost is extremely sensitive to climate change.In particular,aboveground vegetation on permafrost has great sensitivity to the change.The permafrost zone of Northeast China,within middle and high latitudes of the Northern Hemisphere,is the second-largest region of permafrost in China.It is at the southern edge of the Eurasian cryolitho zone.This study analyzed growing-season spatiotemporal variation of the normalization difference vegetation index (NDVI) in this permafrost zone and the correlation between NDVI and climate variables during 1981-2014 based on LTDR,MODIS data set and meteorological data.Mean growing-season NDVI significantly increased by 0.0036 a-1 over the entire permafrost zone.The spatial dynamics of vegetation cover in the zone had strong heterogeneity on the pixel scale.NDVI showing a significant (P<0.05) increasing trend accounted for 80.6% of the permafrost area,and NDVI showing a significant (P<0.05) decreasing trend accounted for 7.7% of the entire study area.The trend of NDVI was variable in different kinds of permafrost zones which increased in order of continuous permafrost zone>discontinuous permafrost zone>sparse island permafrost zone>seasonal frozen region.The proportion of area for maximum increasing trends of NDVI (>0.004) in different permafrost regions was in order of continuous permafrost zone>discontinuous permafrost zone>sparse island permafrost zone>seasonal frozen region.Additionally,at the entire permafrost zone scale,the mean growing-season NDVI was positively significantly correlated with growing-season mean temperature (r=0.79,P<0.01),but weakly negatively related with growing-season precipitation,which indicated that temperature was the dominant influence on vegetation growth during the growing season in the study area.Permafrost degradation in the study area played a positive role in plant growth,especially in continuous permafrost zone and discontinuous permafrost zone.Although increasing ground surface temperature accelerated vegetation cover and growth in the short time,from the long term point of view,permafrost degradation or disappear might hinder vegetation growth.关键词
归一化植被指数/气候变化/植被动态/冻土退化Key words
NDVI/climate change/vegetation dynamics/permafrost degradation引用本文复制引用
郭金停,胡远满,熊在平,闫晓露,任百慧,布仁仓..中国东北多年冻土区植被生长季NDVI时空变化及其对气候变化的响应[J].应用生态学报,2017,28(8):2413-2422,10.基金项目
本文由国家重点基础研究发展计划项目(2013CBA01807)、中国科学院先导专项(XDA05050200)、国家自然科学基金项目(41371198)和中华环境保护基金会“123工程”项目(CEPF2013-123-2-12)资助 This work was supported by the National Basic Research Program of China (2013CBA01807),the Strategic Priority Research Program of Chinese Academy of Sciences (XDA05050200),the National Natural Science Foundation of China (41371198) and the“123" Project of the China Environment Protect Foundation (CEPF2013-123-2-12). (2013CBA01807)