摘要
Permafrost degradation triggered by a warming climate induces significant changes in soil conditions, and further contributes to apparent impacts on vegetation. However, much less is known regarding the difference in net primary productivity（NPP） and the relationships between NPP and warming temperature among different vegetation types and various types of permafrost zone on the Tibetan Plateau. Consequently, remotely sensed land surface temperature（LST） and NPP from the MODIS platform were used to investigate the response of vegetation NPP to warming climate, and the correlations were scaled up for the study region. Our results indicated a notable increase of NPP from west to east, and significantly increased annual NPP along with the increased LST from 2000 to 2010 in the permafrost zone of the Tibetan Plateau. Meanwhile, the increased NPP for various vegetation types and in different types of permafrost zone with relation to warming temperature was revealed. NPP in the continuous permafrost zone had the greatest sensitivity to the changing LST, and forest NPP presented the most obvious response. Positive correlations between NPP and LST at various scales indicated the enhanced effects of warming LST on vegetation carbon sequestration in the permafrost zone of the Tibetan Plateau. In view of the notable response of NPP to warming temperature on this plateau, remote sensing needs to be further employed to reveal the status of permafrost degradation and its related effects on vegetation.
Permafrost degradation triggered by a warming climate induces significant changes in soil conditions, and further contributes to apparent impacts on vegetation. However, much less is known regarding the difference in net primary productivity（NPP） and the relationships between NPP and warming temperature among different vegetation types and various types of permafrost zone on the Tibetan Plateau. Consequently, remotely sensed land surface temperature（LST） and NPP from the MODIS platform were used to investigate the response of vegetation NPP to warming climate, and the correlations were scaled up for the study region. Our results indicated a notable increase of NPP from west to east, and significantly increased annual NPP along with the increased LST from 2000 to 2010 in the permafrost zone of the Tibetan Plateau. Meanwhile, the increased NPP for various vegetation types and in different types of permafrost zone with relation to warming temperature was revealed. NPP in the continuous permafrost zone had the greatest sensitivity to the changing LST, and forest NPP presented the most obvious response. Positive correlations between NPP and LST at various scales indicated the enhanced effects of warming LST on vegetation carbon sequestration in the permafrost zone of the Tibetan Plateau. In view of the notable response of NPP to warming temperature on this plateau, remote sensing needs to be further employed to reveal the status of permafrost degradation and its related effects on vegetation.
基金
The Key Program of Chinese Academy of Sciences, No.KZZD-EW-08-02
The CAS/SAFEA International Partnership Program for Creative Research Teams
The Research Fund from NEGAE, CAS, No.Y2H1071001
The National Natural Science Foundation of China, No.41371403
