Climate Change Creates a Complex Battlefield for Native and Exotic Plant Species

A new study led by Morodoluwa Akin-Fajiye and colleagues, published in the journal AoB PLANTS, delves into how global warming and changes in water availability can impact the competitive dynamics between native and exotic plants.

The research team conducted competition trials involving four plant species native or exotic to Southern interior British Columbia: two exotic forbs, Centaurea stoebe and Linaria vulgaris, and two grasses, the exotic Poa compressa and the native Pseudoroegneria spicata. Their findings highlight how changes in climate can dramatically reshape biotic interactions – the relationships and impacts between different species in an ecosystem.

Importantly, these interactions are not uniform across species. Centaurea stoebe showed higher biomass in conditions of low water and no competition. However, changes in water availability and temperature influenced this species’ shift between facilitation (helping others) and competition. Similar responses were observed in Linaria vulgaris and the grasses, suggesting a nuanced and species-specific adaptation to climate change.

These findings carry significant implications for future biodiversity and ecosystem management. The study revealed that climate change could provide certain exotic species an advantage over native plants. As the globe continues to warm, exotic plants might adapt better and outcompete native species. It’s crucial to consider these biotic interactions when developing mitigation strategies for biodiversity loss and invasive species control.

This research underlines that global warming isn’t just about hotter summers; it fundamentally reshapes our ecosystems. The balance between facilitation and competition can influence which species dominate in a particular habitat, and this research suggests that invasive exotic species could gain the upper hand as the climate changes. This could have cascading impacts on the food chain, biodiversity, and the ecosystem services we rely on, such as pollination and soil enrichment.

In their article, Akin-Fajiye and colleagues conclude:

Taken together, our results indicate that to effectively manage exotic species in light of climate change, biotic interactions between native and exotic species should be considered (Montoya and Raffaelli 2010). We used pair-wise interactions between species, to explore biotic interactions, however, response to climatic drivers in experimental studies may depend on the selected species, or unobserved conditions (McCluney et al. 2012). Experimental outcomes of interactions between target and competitor plants may also differ between seedling and adults. In addition, responses observed under controlled conditions may vary from the field environment. Our findings solidify the necessity of studying climate change impacts on interactions between species and specify the need for studying a suite of species.

Akin-Fajiye et al. 2023.

READ THE ARTICLE
Akin-Fajiye, M., Ploughe, L.W., Greenall, A. and Fraser, L.H. (2023) “Winner and losers: examining biotic interactions in forbs and grasses in response to changes in water and temperature in a semi-arid grassland,” AoB PLANTS, 15(3), p. lad017. Available at: https://doi.org/10.1093/aobpla/plad017.

Cover image. Pseudoroegneria spicata in the Wenatchee foothills, Chelan County Washington. Image: Thayne Tuason / Wikimedia Commons