文献类型：期刊文献

英文题名：Global gross primary productivity and water use efficiency changes under drought stress

作者：Yu, Zhen[1,2,3] Wang, Jingxin[1] Liu, Shirong[2] Rentch, James S.[1] Sun, Pengsen[2] Lu, Chaoqun[3]

第一作者：Yu, Zhen

通信作者：Wang, JX[1];Liu, SR[2]

机构：[1]West Virginia Univ, Div Forestry & Nat Resources, Morgantown, WV 26505 USA;[2]Chinese Acad Forestry, Inst Forest Ecol Environm & Protect, Beijing 100091, Peoples R China;[3]Iowa State Univ, Dept Ecol Evolut & Organismal Biol, Ames, IA 50011 USA

年份：2017

卷号：12

期号：1

外文期刊名：ENVIRONMENTAL RESEARCH LETTERS

收录：;EI(收录号：20170603327204);WOS:【SCI-EXPANDED(收录号:WOS:000394131200001)】；

基金：We gratefully acknowledge the anonymous reviewers for constructive comments for improvement of the manuscript. This study was supported by Agriculture and Food Research Initiative Competitive Grant No. 2012-68005-19703 from the USDA National Institute of Food and Agriculture, China National Science Foundation (No. 31290223) and the Special Research Program for Public-Welfare Forestry (No. 201404201, 201104006).

语种：英文

外文关键词：drought; evapotranspiration; gross primary productivity; water use efficiency; length of recovery days; climate change

摘要：Drought can affect the structure, composition and function of terrestrial ecosystems, yet drought impacts and post-drought recovery potentials of different land cover types have not been extensively studied at a global scale. We evaluated drought impacts on gross primary productivity (GPP), evapotranspiration (ET), and water use efficiency (WUE) of different global terrestrial ecosystems, as well as the drought-resilience of each ecosystem type during the period of 2000 to 2011. Using GPP as biome vitality indicator against drought stress, we developed a model to examine ecosystem resilience represented by the length of recovery days (LRD). LRD presented an evident gradient of high (> 60 days) in mid-latitude region and low (< 60 days) in low (tropical area) and high (boreal area) latitude regions. As average GPP increased, the LRD showed a significantly decreasing trend, indicating readiness to recover after drought, across various land cover types (R 2 = 0.68, p < 0.0001). Moreover, zonal analysis revealed that the most dramatic reduction of the drought-induced GPP was found in the mid-latitude region of the Northern Hemisphere (48% reduction), followed by the low-latitude region of the Southern Hemisphere (13% reduction). In contrast, a slightly enhanced GPP (10%) was evident in the tropical region under drought impact. Additionally, the highest drought-induced reduction of ET was found in the Mediterranean area, followed by Africa. Water use efficiency, however, showed a pattern of decreasing in the Northern Hemisphere and increasing in the Southern Hemisphere. Drought induced reductions of WUE ranged from 0.96% to 27.67% in most of the land cover types, while the increases of WUE found in Evergreen Broadleaf Forest and savanna were about 7.09% and 9.88%, respectively. These increases of GPP and WUE detected during drought periods could either be due to water-stress induced responses or data uncertainties, which require further investigation.