de.mpg.escidoc.pubman.appbase.FacesBean
English
 
Help Guide Disclaimer Contact us Login
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Leaf physiological responses to extreme droughts in Mediterranean Quercus ilex forest

MPS-Authors
There are no MPG-Authors available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Misson, L., Limousin, J. M., Rodriguez, R., & Letts, M. G. (2010). Leaf physiological responses to extreme droughts in Mediterranean Quercus ilex forest. Plant, Cell and Environment, 33, 1898-1910. doi:10.1111/j.1365-3040.2010.02193.x.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0014-4E61-5
Abstract
Global climate change is expected to result in more frequent and intense droughts in the Mediterranean region.To understand forest response to severe drought, we used a mobile rainfall shelter to examine the impact of spring and autumn rainfall exclusion on stomatal (SL) and nonstomatal (NSL) limitations of photosynthesis in a Quercus ilex ecosystem. Spring rainfall exclusion, carried out during increasing atmospheric demand and leaf development, had a larger impact on photosynthesis than autumn exclusion, conducted at a time of mature foliage and decreasing vapour pressure deficit. The relative importance of NSL increased with drought intensity. SL and NSL were equal once total limitation (TL) reached 60%, but NSL greatly exceeded SL during severe drought, with 76% NSL partitioned equally between mesophyll conductance (MCL) and biochemical (BL) limitations when TL reached 100%. Rainfall exclusion altered the relationship between leaf water potential and photosynthesis. In response to severe midsummer drought stress, An and Vcmax were 75% and 72% lower in the spring exclusion plot than in the control plot at the same pre-dawn leaf water potential. Our results revealed changes in the relationship between photosynthetic parameters and water stress that are not currently included in drought parameterizations for modelling applications.