Alien plant species favoured over congeneric natives under experimental climate warming in temperate Belgian climate

Abstract

Climate warming and biological invasions by alien species are two key factors threatening the world's biodiversity. To date, their impact has largely been studied independently, and knowledge on whether climate warming will promote invasions relies strongly on bioclimatic models. We therefore set up a study to experimentally compare responses to warming in native and alien plant species. Ten congeneric species pairs were exposed to ambient and elevated temperature (?3°C) in sunlit, climatecontrolled chambers, under optimal water and nutrient supply to avoid interaction with other factors. All species pairs combined, total plant biomass reacted differently to warming in alien versus native species, which could be traced to significantly different root responses. On average, native species became less productive in the warmer climate, whereas their alien counterparts showed no response. The three alien species with the strongest warming response (Lathyrus latifolius, Cerastium tomentosum and Artemisia verlotiorum) are currently non-invasive but all originate from regions with a warmer climate. Still, other alien species that also originate from warmer regions became less or remained equally productive. Structural or ecophysiological acclimation to warming was largely absent, both in native and alien species, apart from light-saturated photosynthetic rate, where warming tended to restrain the native but not the alien species. A difference in the capacity to acclimate photosynthetic rates to the new climate may therefore have caused the contrasting biomass response. Future experiments are needed to ascertain whether climate warming can effectively tip the balance between native and alien competitors.

The effects of climate warming and disturbance on the colonization potential of ornamental alien plant species

“…This contrasts with the positive responses of introduced species to increased temperatures observed elsewhere (e.g. Verlinden & Nijs ; Chuine et al . ; He, Li & Peng ; Liu et al .…”

A Congeneric Comparison Shows That Experimental Warming Enhances the Growth of Invasive Eupatorium adenophorum

“…In this experiment, the day- and night-warming might induce the occurrence of photosynthetic overcompensation in E. adenophorum , while the daily-warming did not yield such an effect. Verlinden & Nijs (2010) found that invasive plants showed no response to daily-warming [15]. This is consistent with our findings.…”

Functional traits modulate the response of alien plants along abiotic and biotic gradients

“…Indeed, we also found a similar trait–environment interaction in our model of native species distribution (Figure ). But in addition, warmer conditions provided a specific advantage to alien species over most native species in these grasslands (Verlinden & Nijs, ), because natives on average did not respond as positively to GDD as did alien species (Figure ). This has interesting implications for the future of invasions in grasslands under predicted scenarios of climate change (Bradley et al, ), because alien species will be on average more favoured than natives by a rapidly warming climate, particularly in climatically harsh environments, such as mountain ranges (Carboni et al, ).…”