On the role of plant volatiles in anthropogenic global climate change

Abstract

Biogenic volatile organic compound (BVOC) emissions from terrestrial ecosystems undergo rapid oxidation in the atmosphere that affects multiple warming and cooling climate pollutants. Since the preindustrial, BVOC-chemistry-climate interactions have been strongly influenced by anthropogenic changes in land cover, pollution emissions, and the physical climate state. Here, an Earth system model is applied to quantify the effects of BVOC emissions on the global radiation balance in the 1850s and 2000s including changes to tropospheric ozone, methane, and direct aerosol-radiation interactions. The net chemical forcing of global climate due to all known anthropogenic influences on BVOC emissions is À0.17 Wm À2 (cooling) that offsets the +0.10 Wm À2 (warming) due to anthropogenic VOC emissions from fossil fuel use and industry for this time period. BVOC emissions need to be included in assessments of anthropogenic radiative forcing.

Increases in volatile organic compound emissions of Scots pine in response to elevated ozone and warming are modified by herbivory and soil nitrogen availability

“…Ozone was generated from pure oxygen with an ozone generator (Ozone Generator G21, Pacific Ozone Technology Inc., Brentwood, CA, USA) and released into the ozone treatment plots through vertical (Räisänen et al 2008), ozone (Heiden et al 1999), (sawfly) herbivory (Ghimire et al 2013) and increased N availability (increased resin ducts and terpenoids, Björkman et al 1998) as single factors on BVOC emissions of Scots pine, as well feedback reactions of BVOCs on the biotic and abiotic factors: net cooling (Unger 2014), formation and breakdown of ozone (Holopainen 2011), direct and indirect herbivory resistance (Mumm and Hilker 2006). Some interconnections between abiotic and abiotic factors are shown: Warming has potential to increase N availability of the soil (Contosta et al 2011), N affects herbivory performance (Björkman et al 1991;Holopainen et al 1995), and warming affects herbivore abundance and distribution (Berggren et al 2009).…”

“…Based on our study, and assuming responses in seedlings and mature trees are similar, nitrogen availability and herbivory can be important modifiers of global change feedback reactions, as indicated by their interactions with ozone and temperature. For example, if BVOCs have a net cooling effect on climate (Unger 2014), high nitrogen availability would enhance that effect in the near-future climate. While intensive herbivory and ozone together amplify the secondary aerosol formation from BVOCs (Joutsensaari et al 2015), long-term effects in the field may be more complex, as suggested by reduced emission in interaction by herbivory and ozone observed in this study.…”

“…BVOCs react with atmospheric gases, participate in both formation and breakdown of ozone, affect the lifetime of the greenhouse gas methane and form secondary organic aerosols (SOA) to increase sunscreen (Hao et al 2011;Holopainen 2011). Globally, BVOCs are estimated to have a net cooling effect on climate (Unger 2014). Factors of climate change, such as ozone and warming, in turn, affect BVOC emissions of plants (Peñuelas and Staudt 2010).…”

Uncertainties in isoprene photochemistry and emissions: implications for the oxidative capacity of past and present atmospheres and for climate forcing agents

“…She estimated a net cooling of −0.11 ± 0.17 W m −2 , which is comparable in magnitude but opposite in sign to the net forcing from the changes in surface albedo and land carbon release associated with cropland expansion. When other known anthropogenic influences on biogenic VOC emissions are also considered, the net global climate forcing is estimated to be −0.17 W m −2 (Unger, 2014b). Our work demonstrates that reducing the uncertainties on such an estimate will require improvements in our knowledge of isoprene photochemistry and CO 2 sensitivity, as well as reconciling model estimates of land-cover change over the industrial period.…”

Herbivore‐induced plant volatiles accurately predict history of coexistence, diet breadth, and feeding mode of herbivores

“…In addition, anthropogenic climate change leads to many species shifting or extending their ranges pole-wards, thereby invading new environments (Chen et al, 2011;Bebber et al, 2013). Whereas the effects of climatic factors, for example CO 2 , ozone and temperature, on HIPV emissions have received ample attention (Laothawornkitkul et al, 2009;Yuan et al, 2009;Dicke & Loreto, 2010;Penuelas & Staudt, 2010;Unger, 2014), the effects of exotic herbivores on HIPV production by native plant species have been greatly neglected. The specificity of HIPVs induced by different even closely relatedherbivore species (see e.g.…”