A potential novel source of information for screening and monitoring the impact of exotic plants on ecosystems

Exotic invasive species often affect the pools and fluxes of carbon, nutrient elements, and energy, but there are few sources of information that permit these effects to be anticipated. Some plant traits, such as growth rates and tissue nutrient content, are known to influence the ecosystem process, but information about these traits is often not available. I propose that plant secondary chemistry may be a useful trait for assessing the likelihood of ecosystem (and community) impacts. Information about such traits is readily available from several sources, rendering it a good candidate for screening and monitoring programs. Plant secondary chemicals affect a variety of ecosystem processes, largely through their direct and indirect impacts on soil microbial community composition and function. They also have well-known effects on human physiology, as evidenced in the numerous plant-derived bioactive compounds used for their medicinal and other physiological effects. There is a large amount of information available about plant secondary chemistry due to its role in herbal medicine, dietary supplements and the emerging field of nutraceuticals. This information includes databases and traditional texts in ethnobotany, plant chemistry, and alternative medicine. I review evidence that secondary compounds are widespread in invasive species and affect soil microbial communities and microbially-mediated ecosystem processes. Invasion ecology may profit from collaborations with a novel group of scientists, including those in ethnobotany, nutraceuticals, plant chemistry and alternative medicine.