Abstract
AbstractDuring the last decades, plant die‐off has been reported worldwide as a result of increased frequency and intensity of extreme drought events. From a niche perspective, a species performance should decrease as the climatic conditions defining a drought event differ from those characterizing the species climatic niche (the average conditions experienced by the species). Species distribution models (SDMs) can potentially be used to test the link between species performance and their climatic niche by means of climatic suitability indexes. We studied the remaining green canopy of 18 woody species co‐occurring in a Mediterranean shrubland from the central Iberian Peninsula that experienced a severe die‐off following an extreme drought event. We found that the suitability of the climatic conditions estimated by SDMs strongly declined for all species during the extreme drought event. Species die‐off was significantly explained by the decrease in climatic suitability during the event, estimated as the ratio between the historic and the extreme event climatic suitability. Species with high occupancy levels across the landscape exhibited higher die‐off likely because (1) these species have short life‐span and mortality would be compensated by later high recruitment or (2) populations of rare species may have experienced local adaptation to drier conditions. Our results indicate that extreme drought events can have a negative effect, even in shrubland communities living in arid environments. Also, we develop a new approach that connects population‐level responses to species climatic niches through SDMs, and it can be applied to predict community responses to strong climatic variability, such as drought events.
Highlights
Climate change is increasing the intensity, frequency, and length of droughts through increased temperatures and reduced precipitation across many regions of the globe (IPCC 2013)
Our results demonstrate the link between localscale processes, such as drought-induced population die-off during extreme climatic events, and the species climatic niche estimated from distribution patterns at a biogeographic scale
We show that it is possible to interpret local processes at plant population level, such as drought-induced die-off, from the position of populations relative to their respective species climatic niche using Species distribution models (SDMs)
Summary
Climate change is increasing the intensity, frequency, and length of droughts through increased temperatures and reduced precipitation across many regions of the globe (IPCC 2013). Many of these regions are experiencing increased aridity (D’Odorico et al 2013) and extreme drought events, leading to tree and shrub die-off episodes worldwide (Allen et al 2010, Greenwood et al 2017). These events trigger changes in community structure and composition that may promote new communities with different ecological characteristics (Lloret et al 2012). The extent to which ecosystem features change as a result of drought events depends on species’ performance under drought (e.g., die-off). Species’ performance under drought can be tied to niche theory through the concept of fundamental niche proposed by Hutchinson (1957).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
