COS 53-9
Climate impacts on belowground function via shifts in plant chemistry permeating the soil profile
The primary drivers of belowground activity, like water availability and temperature, may also impose strong indirect influences on soil function through altered plant chemistry. Studies already investigate the direct impacts of forecasted climate change on soil function, but it is unclear to what extent future climate will impact belowground function via shifts in the plant chemical constituents permeating the soil profile, by both individual plasticity responses of plant species and/or shifts in plant community structure. Intraspecific shifts in chemical composition of the leaf tissue may occur as a result of the species’ physiological response to altered environmental conditions, like elevated CO2 and temperature, or these environmental changes may also result plant community shifts, which in turn may impact belowground function via soluble plant compounds entering the soil profile. The primary objective of this study was to assess individual chemical plasticity and species-specific leaf chemistry, as well as corresponding room temperature water-extractable leachate, of four prominent plants from southern Wyoming grassland habitats: Artemisia frigida, Linaria dalmatica, Centaurea diffusa, and Bouteloua gracilis. The belowground impacts of altered leachate chemistry were examined by applying homogenized-local soils to the various leachate treatments in an incubation and monitoring soil function.
Results/Conclusions
Intraspecific differences in leaf and leachate chemistry were determined from detailed chemical analysis, while C:N ratios were comparable amongst the examined plant species. Additionally, there was a correlation between plant phylogeny and corresponding leaf chemistry, while the signal broke down with the leachate chemistry: phylogeny. More specifically, the native A. frigida and invasive L. dalmatica exhibited the most distinctive leaf chemistry, while interspecific differences in leachate chemistry were less prominent, and even less so with intraspecific shifts due to long-term altered CO2 and warming. Using anticipated shifts from other research groups, we will eventually be able to apply potential plant community shifts to our belowground findings. This study suggests that the indirect impacts of climate, including the altered surrounding biotic environment, should be considered when conjecturing about soil function under forecasted climate conditions.