Changes in biodiversity impact atmospheric chemistry and climate through plant volatiles and particles

Abstract

Climate extremes in tandem with biodiversity change affect emissions of biogenic volatile organic compounds (BVOCs) from plants and, as a result, the formation of biogenic secondary organic aerosols (BSOA). The resulting BSOA can have a wide variety of impacts, such as on Earth′s radiative balance and cloud formation. However, it is unclear to what extent changes in BVOC emissions and BSOA formation are related to biodiversity. Here we present a conceptual framework of the relationships between biodiversity and BVOC emissions based on our current mechanistic understanding and existing knowledge. We tested parts of this framework using a tree diversity experiment as a case-study. We find that the amount of BVOCs in most cases decreases with biodiversity, implying that tree mixtures produce less than expected BVOC compared to tree monocultures. However, some BSOA compounds increased and some decreased relative to what is expected from monocultures. Based on these mixed results, we recommend further field measurements on the patterns of BVOC emission and BSOA formation across biodiversity gradients to improve our understanding and accuracy of the amounts of the compounds emitted. Future studies need a multidisciplinary approach to open a new research nexus where the fields of climate science, biology and atmospheric chemistry interact.

Biodiversity and Climate Extremes: Known Interactions and Research Gaps

“…Intriguingly, a scoping measurement study by Sanaei et al. (2023) found that increased taxonomic biodiversity might result in lower total BVOC emissions compared to the cumulative emissions of individual species. These findings highlight the need for further research, particularly concerning how BVOC oxidation modifies particles through BSOA and the subsequent effects on clouds, precipitation and climate.…”

“…Biodiversity controls how ecosystems absorb pollutants, store carbon, or provide numerous natural resources. The regulation of water, gas, and energy fluxes, and the release and absorption of primary emitted particles (Fröhlich‐Nowoisky et al., 2016; Sanaei et al., 2023) by functional and structural diversity and landscape heterogeneity, contributes to the regulation of land‐surface climate feedbacks and can thereby affect local to global climate (Beugnon et al., 2024; Bonan, 2008; Duveiller et al., 2021; Graf et al., 2020; Miralles et al., 2019; Santanello et al., 2018; Ukkola et al., 2018).…”