Mortality of resprouting chaparral shrubs after a fire and during a record drought : physiological mechanisms and demographic consequences

© 2013 John Wiley & Sons Ltd.

Bibliographische Detailangaben
Veröffentlicht in:Global change biology. - 1999. - 20(2014), 3 vom: 19. März, Seite 893-907
1. Verfasser: Pratt, R Brandon (VerfasserIn)
Weitere Verfasser: Jacobsen, Anna L, Ramirez, Aaron R, Helms, Anjel M, Traugh, Courtney A, Tobin, Michael F, Heffner, Marcus S, Davis, Stephen D
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2014
Zugriff auf das übergeordnete Werk:Global change biology
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Adenostoma Ceanothus carbohydrate starvation cavitation chamise wildfire xylem mehr... Water 059QF0KO0R
Beschreibung
Zusammenfassung:© 2013 John Wiley & Sons Ltd.
We examined postfire regeneration of chaparral shrubs during an intense drought. This study focused on the demography and physiology of shrub species that resprout from a basal lignotuber following fire. We found significant levels of resprout mortality when intense drought occurred in the year following fire during the period of shrub recovery. Three of the seven sampled resprouting species had the greatest or near greatest levels of mortality ever recorded when compared to previous studies. Most shrub mortality occurred during the drought after individuals had resprouted (i.e. individuals survived fire, resprouted and then subsequently died). Physiological measurements of species with high mortality suggested that resprout stems were highly embolized and xylem hydraulic conductivities were close to zero during the peak of the drought. In addition, lignotubers of two of the three species experiencing high mortality were depleted of starch. Population densities of most shrub species declined after the drought compared with their prefire levels, with the exception of one drought tolerant obligate seeding species. Resprouting shrub species may deplete their carbohydrate reserves during the resprouting process, making them particularly vulnerable to drought because of the need to transpire water to acquire the CO2 that is used to supply energy to a large respiring root system. Drought appears to interact with fire by altering postfire shrub recovery and altering species abundances and composition of chaparral communities
Beschreibung:Date Completed 16.09.2014
Date Revised 25.11.2016
published: Print-Electronic
Citation Status MEDLINE
ISSN:1365-2486
DOI:10.1111/gcb.12477