文献类型：期刊文献

英文题名：Drought timing influences the sensitivity of a semiarid grassland to drought

作者：Li, Linfeng[1,2] Qian, Ruyan[3] Liu, Wenjun[4] Wang, Weijin[2,5] Biederman, Joel A.[6] Zhang, Biao[1] Kang, Xiaoming[7,8,9] Wen, Fuqi[3] Ran, Qinwei[3] Zheng, Zhenzhen[3] Xu, Cong[10] Che, Rongxiao[11] Xu, Zhihong[2] Cui, Xiaoyong[3,12,13] Hao, Yanbin[3,12,13] Wang, Yanfen[3,12,13]

第一作者：Li, Linfeng

通信作者：Hao, YB[1]

机构：[1]Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China;[2]Griffith Univ, Sch Environm & Sci, Environm Futures Res Inst, Brisbane, Qld 4111, Australia;[3]Univ Chinese Acad Sci, Coll Life Sci, Beijing 100049, Peoples R China;[4]YunnanUniv, Sch Ecol & Environm Sci, Kunming 650091, Yunnan, Peoples R China;[5]Univ Queensland, Sch Agr & Food Sci, Brisbane, Qld 4072, Australia;[6]ARS, Southwest Watershed Res Ctr, Tucson, AZ 85719 USA;[7]Chinese Acad Forestry, Inst Wetland Res, Beijing 100091, Peoples R China;[8]Beijing Key Lab Wetland Serv & Restorat, Beijing 100091, Peoples R China;[9]Tibetan Autonomous Prefecture Aba, Sichuan Zoige Wetland Ecosyst Res Stn, Beijing 624500, Peoples R China;[10]Chinese Acad Sci, Aerosp Informat Res Inst, State Key Lab Remote Sensing Sci, Beijing 100101, Peoples R China;[11]Yunnan Univ, Inst Int Rivers & Ecosecur, Kunming 650091, Yunnan, Peoples R China;[12]Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China;[13]Univ Chinese Acad Sci, Chinese Acad Sci, Yanshan Earth Crit Zone & Surface Fluxes Res Stn, Beijing 10049, Peoples R China

年份：2022

卷号：412

外文期刊名：GEODERMA

收录：;EI(收录号：20220311487407);Scopus(收录号：2-s2.0-85122950327);WOS:【SCI-EXPANDED(收录号:WOS:000913198900002)】；

基金：This project was funded by the CAS Strategic Priority Research Programme (A) (Grant No. XDA19030202), the National Natural Science Foundation of China (Grant No. 32101313) and Fundamental Research Funds for the Central Universities (Grant No. E1E40511). J. Biederman's contributions were supported by the US Department of Agriculture, Agricultural Research Service. USDA is an equal-opportunity employer. Great thanks for the help of the Inner Mongolia Grassland Ecosystem Research Station.

语种：英文

外文关键词：Carbon cycling; Climate extremes; ECEB-II; Seasonal timing; Sensitivity; Stability

摘要：Quantifying the sensitivity of ecosystems to droughts, particularly with different seasonal timing, could improve our predictions of ecosystem-climate feedbacks, but few experiments have explicitly addressed seasonal timing per se effects on ecosystem sensitivity to droughts. Here, we present a seasonal timing x drought manipulation experiment to examine sensitivity (relative change in response parameters to the relative change in precipitation) of key ecosystem processes (community biomass and ecosystem CO2 fluxes) to pulse-drought with different seasonal timing (early, middle or late) on a temperate semiarid grassland. We found belowground and total biomass were positively sensitive (i.e. ecological processes promoted by droughts and vice versa) to early and middle droughts but negatively sensitive to late drought while aboveground biomass was insensitive to all droughts. Ecosystem CO2 fluxes had the largest negative sensitivity to early drought and smallest negative sensitivity to middle drought, although gross ecosystem production showed larger negative response to droughts than ecosystem respiration, leading to reduction in net ecosystem production, regardless of seasonal timing. Our results highlight the crucial role of seasonal drought timing in regulating sensitivity of key carbon cycle processes to droughts and suggest that droughts at plant peak stage cause the least detrimental ecological consequences.