张欣等:Impact of prolonged drought on rainfall use efficiency using MODIS data across China in the early 21st century
被阅读 1255 次
2014-08-22

Impact of prolonged drought on rainfall use efficiency using MODIS data across China in the early 21st century
作者:Zhang, X (Zhang, Xin)[ 1,2,3 ] ; Moran, MS (Moran, M. Susan)[ 4 ] ; Zhao, X (Zhao, Xiang)[ 1,2,5 ] ; Liu, SH (Liu, Suhong)[ 1,2,3 ] ; Zhou, T (Zhou, Tao)[ 6 ] ; Ponce-Campos, GE (Ponce-Campos, Guillermo E.)[ 4,7 ] ; Liu, F (Liu, Feng)[ 1,2,3 ]
REMOTE SENSING OF ENVIRONMENT
卷: 150  页: 188-197
DOI: 10.1016/j.rse.2014.05.003
出版年: JUL 2014

摘要
Frequency and severity of droughts are projected to increase in many regions, and their effects on temporal dynamics of the terrestrial carbon cycle remain uncertain. Ecosystem net primary productivity (NPP) is a key component of the carbon cycle, and rainfall use efficiency (RUE = NPP/precipitation) is an important measure of ecosystem stability and resilience. Here we investigated the temporal patterns of NPP and RUE and their key driving climate factors, during the early 21st century drought for four biomes in China: Needleleaf forest, Broadleaf forest, Woody savannas, and Grassland. Estimates of regional-scale NPP were based on the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) MOD17 NPP product. Our results confirmed recent findings that the impact of current-year precipitation on NPP was confounded by an array of biotic and abiotic factors. Whereas, the RUE responded strongly to variations in current- and previous-year drought for all the four biomes and the four biomes combined. We found that a dry year preceded by a wet year resulted in the highest RUE, and conversely, a wet year preceded by a dry year resulted in the lowest RUE. This was attributed to the legacy effect of precipitation changes in both wet and dry years, and to the resilience of the biomes in the dry years. Based on these results, we developed and validated a model of RUE based on the Palmer Drought Severity Index (PDSI) of both current and previous years which works well for these four biomes and all biomes combined. This model is particularly useful for understanding the impact of prolonged drought at the landscape scale because it is based on accessible satellite data and available meteorological data and the results have been tested across four major biomes. Published by Elsevier Inc.

通讯作者地址: Moran, MS (通讯作者)
USDA ARS Southwest Watershed Res, Tucson, AZ 85719 USA.
地址:
[ 1 ] Beijing Normal Univ, State Key Lab Remote Sensing Sci, Beijing 100875, Peoples R China
[ 2 ] Chinese Acad Sci, Inst Remote Sensing Applicat, Beijing, Peoples R China
[ 3 ] Beijing Normal Univ, Sch Geog, Beijing 100875, Peoples R China
[ 4 ] USDA ARS Southwest Watershed Res, Tucson, AZ 85719 USA
[ 5 ] Beijing Normal Univ, Coll Global Change & Earth Syst Sci, Beijing 100875, Peoples R China
[ 6 ] Beijing Normal Univ, State Key Lab Earth Surface Proc & Resource Ecol, Beijing 100875, Peoples R China
[ 7 ] Univ Arizona, Tucson, AZ 85721 USA