The Effect of Climate Change on Composition and Emissions of Plant Volatile Organic Compounds and Shifts in Plant-Pollinator Interactions

Abstract

As climate change continues with increased temperatures, drought conditions, ozone, and carbon dioxide levels, a consequence is changes in volatile organic compound (VOCs) composition and emissions and potential changes in plant-pollinator interactions. These compounds and interactions play a critical role in maintaining healthy ecosystems feeding the world's growing human population. Although there are numerous studies on individual plants, their VOCs, and pollinator interactions, there is a lack of comparison studies that highlight trends in volatile composition and emissions. Therefore, I examined 30 published studies related to these important areas. I examined how abiotic factors such as drought, increased levels of carbon dioxide and ozone, and increased temperatures affect VOC emissions. Of interest were monoterpenes and terpenoids. I then examined how the changes in emissions and composition might influence plant-pollinator interactions. Using the keywords climate change, plant volatile organic compounds, plant-pollinator interactions, and bees, I searched Google Scholar, the Montana State University Library, and textbooks. I compared studies on different classes of VOCs and in different plant species and highlighted the most important changes found. Ultimately, there were no specific trends in VOC composition and emissions or resulting plant-pollinator interactions influenced by the abiotic factors I targeted. Both VOCs and plant-pollinator interactions increased and decreased independent of one another. One monoterpene, beta-pinene, increased 147% in emissions under drought conditions while a sesquiterpene, alpha-gurjenene, decreased 200% in emissions under drought conditions. These responses may indicate that the effects of climate change on VOC biosynthesis are not constant, making it difficult to predict these fluxes. Due to this gap in knowledge, management of ecosystems and agricultural cropping systems will be more difficult as there is not a specific prescribed way to manage these changes. By possibly shifting our reliance on specific pollinators to a more diverse pollinator population and by exploiting VOCs in management we can mitigate the potential pollination losses due to changes in VOCs.