Drought and resprouting plants

Abstract

SummaryMany species have the ability to resprout vegetatively after a substantial loss of biomass induced by environmental stress, including drought. Many of the regions characterised by ecosystems where resprouting is common are projected to experience more frequent and intense drought during the 21st Century. However, in assessments of ecosystem response to drought disturbance there has been scant consideration of the resilience and post-drought recovery of resprouting species. Systematic differences in hydraulic and allocation traits suggest that resprouting species are more resilient to drought-stress than nonresprouting species. Evidence suggests that ecosystems dominated by resprouters recover from disturbance more quickly than ecosystems dominated by nonresprouters. The ability of resprouters to avoid mortality and withstand drought, coupled with their ability to recover rapidly, suggests that the impact of increased drought stress in ecosystems dominated by these species may be small. The strategy of resprouting needs to be modelled explicitly to improve estimates of future climate-change impacts on the carbon cycle, but this will require several important knowledge gaps to be filled before resprouting can be properly implemented.

Intensifying postfire weather and biological invasion drive species loss in a Mediterranean-type biodiversity hotspot

“…The decline in graminoid and herb species richness is consistent with findings from longterm studies of climate change impacts on Californian grasslands (1) and the Siskiyou mountain herb flora of southern Oregon (30). The observed differences in the response of major growth forms and fire-response types to climate change could well drive major shifts in ecosystem structure and function (13,17,18,31). For example, graminoids and herbs form the majority of the flammable fuel load in Fynbos communities (53), so changes in their cover-abundance may alter fire behavior.…”

“…Shallow-rooted perennial species, including most graminoids and herbs in Fynbos, are likely to be most sensitive, as reported in other ecosystems (30). A recent global review proposes that species that resprout are more resilient to drought stress, but reports that empirical studies are few and conflicting (31). Fynbos studies report a higher proportion of resprouters in sites with wetter soils at the scale of both local communities and across biogeographic regions (18,32,33), invoking higher moisture requirements for establishment and regeneration, owing to the need to allocate resources to burls or lignotubers.…”

Xylem embolism refilling and resilience against drought‐induced mortality in woody plants: processes and trade‐offs

“…The microCT technique has provided evidence for embolism refilling in the xylem of grapevine (Brodersen and McElrone 2013) but also revealed no novel refilling occurred in coastal redwoods, the Sequoia . Interestingly, Sequoia is a resprouter (Zeppel et al 2015), which may be an alternative or complementary recovery strategy to embolism refilling. Indeed, much of our knowledge of embolism refilling has been conducted on only a few woody species, including grapevines (Choat et al 2010;Zufferey et al 2011;Chitarra et al 2014), Bay laurel (Trifilo`et al 2014a) and poplar (Bloemen et al 2016).…”

Sequence of plant responses to droughts of different timescales: lessons from holm oak (Quercus ilex) forests

“…A transient quiescence of growth has also been reported for Mediterranean conifers (Camarero et al 2010;Vieira et al 2014) and forbs (Olano et al 2013). Large below-and above-ground bud banks are also characteristically associated with Mediterranean vegetation (Canadell and Lopez-Soria 1998;Klimešová and Klimeš 2007) and its capacity to recover from fires but are also relevant after extreme droughts (Zeppel et al 2015). Furthermore, resprouting species share a suite of ecophysiological and anatomical traits (Hernández et al 2011;Vilagrosa et al 2014), so their response to drought should be similar, albeit with differences in sensitivity.…”

“…We demonstrate how this information is not only useful for a better understanding of the response of Q. ilex to environmental change but also to show how the temporal scale is crucial for predicting the responses of plants to the increases in drought projected by global circulation models (IPCC 2013). The mechanisms and traits that Q. ilex possesses to resist and recover from droughts (Table 1) are shared by many plant species from Mediterranean-type ecosystems and other droughtprone ecosystems, especially by resprouting angiosperms (Zeppel et al 2015). Therefore, the insights provided by this review are, to some extent, representative of the ecology of Mediterranean vegetation under current climate and can serve for indicating expected climate change responses.…”