Unravelling the functions of biogenic volatiles in boreal and temperate forest ecosystems

Maja Šimpraga,Toini Holopainen,Rajendra P Ghimire,Anne Kasurinen,Jouni Sorvari,Dominique Van Der Straeten,Minna Kivimäenpää,Sandy Adriaenssens,Jarmo K Holopainen,James D Blande

doi:10.1007/s10342-019-01213-2

Abstract

Living trees are the main source of biogenic volatile organic compounds (BVOCs) in forest ecosystems, but substantial emissions originate from leaf and wood litter, the rhizosphere and from microorganisms. This review focuses on temperate and boreal forest ecosystems and the roles of BVOCs in ecosystem function, from the leaf to the forest canopy and from the forest soil to the atmosphere level. Moreover, emphasis is given to the question of how BVOCs will help forests adapt to environmental stress, particularly biotic stress related to climate change. Trees use their vascular system and emissions of BVOCs in internal communication, but emitted BVOCs have extended the communication to tree population and whole community levels and beyond. Future forestry practices should consider the importance of BVOCs in attraction and repulsion of attacking bark beetles, but also take an advantage of herbivore-induced BVOCs to improve the efficiency of natural enemies of herbivores. BVOCs are extensively involved in ecosystem services provided by forests including the positive effects on human health. BVOCs have a key role in ozone formation but also in ozone quenching. Oxidation products form secondary organic aerosols that disperse sunlight deeper into the forest canopy, and affect cloud formation and ultimately the climate. We also discuss the technical side of reliable BVOC sampling of forest trees for future interdisciplinary studies that should bridge the gaps between the forest sciences, health sciences, chemical ecology, conservation biology, tree physiology and atmospheric science.

Highlights

Forests occupy one-third of the Earth’s land area, and they are one of the major components of the global carbon cycle, providing substantial storage (~ 45%) of terrestrial carbon (Bonan 2008)
biogenic volatile organic compounds (BVOCs) in forests have a multitude of functions at various scales, and it is obvious that due to the enormous diversity of primary BVOCs and their atmospheric reaction products, we only understand a minor part of their role in forest ecosystem function
Plants face a diverse range of metabolic and physiological challenges, which can build up when the climate is changing rapidly

Summary

Introduction

Forests occupy one-third of the Earth’s land area, and they are one of the major components of the global carbon cycle, providing substantial storage (~ 45%) of terrestrial carbon (Bonan 2008). In addition to CO2 fixation, forests affect global climate by adding atmospheric humidity through evapotranspiration (Bonan 2008) and by emissions of biogenic volatile organic compounds (BVOCs) (Fig. 1).

Results

Conclusion