Invasive plants and climate change

This chapter provides a broad overview of the interactions between invasive alien plants and climate change. Invasive alien plants are harmful nonnative plant species that have been introduced by humans outside of their “natural” geographical range. Both climate change and alien plant invasions result from human activities and can cause major environmental and socioeconomic damage. Although they can operate as independent environmental and economic threats, they can also interact. Climate change can facilitate alien plant invasions (1) by altering background environmental conditions; (2) by increasing disturbance through extreme climatic events; and (3) through human responses to climate change. While all plants, regardless of whether they are native or alien, will likely be affected by environmental change, it is widely expected that climate change will favor invasive alien plants at the expense of native plants. The way in which invasive alien plants impact the environment (e.g., modifying hydrology and soil properties, altering fire regimes) can to some extent either contribute to or exacerbate the effect of climate change. Here, we consider why and how climate change is predicted to exacerbate alien plant invasions and provide examples of how invasive alien plants can contribute to climate change. We first briefly describe what makes a plant invasive, how and why a plant becomes invasive, what stages must it go through, and what the drivers of invasion are.