文献类型：期刊文献

英文题名：Recovery of trees from drought depends on belowground sink control

作者：Hagedorn, Frank[1] Joseph, Jobin[1,2] Peter, Martina[1] Luster, Jorg[1] Pritsch, Karin[3] Geppert, Uwe[3] Kerner, Rene[3] Molinier, Virginie[1] Egli, Simon[1] Schaub, Marcus[1] Liu, Jian-Feng[4] Li, Maihe[1] Sever, Krunoslav[5] Weiler, Markus[2] Siegwolf, Rolf T. W.[6] Gessler, Arthur[1,7,8] Arend, Matthias[1,9]

第一作者：Hagedorn, Frank

通信作者：Arend, M[1];Arend, M[2]

机构：[1]Swiss Fed Inst Forest Snow & Landscape Res WSL, Zurcherstr 111, CH-8903 Birmensdorf, Switzerland;[2]Univ Freiburg, Fac Environm & Nat Resources, Chair Hydrol, Fahnenbergpl, D-79098 Freiburg, Germany;[3]German Res Ctr Environm Hlth GmbH, Helmholtz Zentrum Munchen, Inst Biochem Plant Pathol, Ingolstaedter Landstr 1, D-85764 Neuherberg, Germany;[4]Chinese Acad Forestry, Res Inst Forestry, Xiangshan Rd, Beijing 100091, Peoples R China;[5]Univ Zagreb, Dept Forest Genet Dendrol & Bot, Fac Forestry, Svetosimunska 25, HR-10000 Zagreb, Croatia;[6]Paul Scherrer Inst, Ecosyst Fluxes Grp, Lab Atmospher Chem, CH-5232 Villigen, Switzerland;[7]Leibnitz Ctr Agr Landscape Res ZALF, Inst Landscape Biogeochem, Eberswalder Str 84, D-15374 Muncheberg, Germany;[8]Berlin Brandenburg Inst Adv Biodivers Res BBIB, Altensteinstr 6, D-14195 Berlin, Germany;[9]Tech Univ Munich, Sch Forest Sci & Resource Management, Hans Carl von Carlowitz Pl 2, D-85354 Freising Weihenstephan, Germany

年份：2016

卷号：2

期号：8

外文期刊名：NATURE PLANTS

收录：;Scopus(收录号：2-s2.0-84985916019);WOS:【SCI-EXPANDED(收录号:WOS:000385010500004)】；

基金：We thank P. Bleuler for technical assistance and for maintaining the model ecosystem facility. We also thank B. Meier, R. Appenzeller, Y. Bicker, D. Brodlin, D. Christen, N. Hajjar, R. Kochli, F. Schreyer and A. Zurcher for their help with sampling and measurements, and F. Buegger, L. Schmidt and A. Schlumpf for completing the isotope analysis. We are grateful to M. Dawes for critically reading and providing helpful comments on the manuscript. This work was supported by funding from the Swiss Federal Institute for Forest, Snow and Landscape Research WSL and the Swiss Federal Office for the Environment FOEN.

语种：英文

摘要：Climate projections predict higher precipitation variability with more frequent dry extremes(1). CO2 assimilation of forests decreases during drought, either by stomatal closure(2) or by direct environmental control of sink tissue activities(3.) Ultimately, drought effects on forests depend on the ability of forests to recover, but the mechanisms controlling ecosystem resilience are uncertain(4). Here, we have investigated the effects of drought and drought release on the carbon balances in beech trees by combining CO2 flux measurements, metabolomics and (CO2)-C-13 pulse labelling. During drought, net photosynthesis (A(N)), soil respiration(R-S) and the allocation of recent assimilates below ground were reduced. Carbohydrates accumulated in metabolically resting roots but not in leaves, indicating sink control of the tree carbon balance. After drought release, R-S recovered faster than A(N) and CO2 fluxes exceeded those in continuously watered trees for months. This stimulation was related to greater assimilate allocation to and metabolization in the rhizosphere. These findings show that trees prioritize the investment of assimilates below ground, probably to regain root functions after drought. We propose that root restoration plays a key role in ecosystem resilience to drought, in that the increased sink activity controls the recovery of carbon balances.