General patterns of acclimation of leaf respiration to elevated temperatures across biomes and plant types

Abstract

of origin and growth form, but respiration was not completely homeostatic across temperatures in the majority of cases. Leaves that developed at a new temperature had a greater capacity for acclimation than those transferred to a new temperature. We conclude that leaf respiration of most terrestrial plants can acclimate to gradual warming, potentially reducing the magnitude of the positive feedback between climate and the carbon cycle in a warming world. More empirical data are, however, needed to improve our understanding of interspecific variation in thermal acclimation capacity, and to better predict patterns in respiratory carbon fluxes both within and across biomes in the face of ongoing global warming. Keywords Climate change · Global patterns · Metaanalysis · Plant ecophysiology · Warming IntroductionClimate warming is predicted to increase the release of carbon dioxide (CO 2 ) from the terrestrial biosphere into the atmosphere, thus triggering a positive climate-terrestrial carbon feedback that accelerates warming (Cox et al. 2000;Luo 2007). However, plant respiration (non-photorespiratory mitochondrial CO 2 release) may be downregulated in response to warming of temperature regimes over days to months, and such acclimation may reduce the potential decline in net primary productivity (NPP) (King et al. 2006;Smith and Dukes 2013;Slot et al. 2014a). High and mid-latitude ecosystems experience more rapid, and greater degrees of warming than the tropics (Stocker et al. 2013), and temperature effects on plant and ecosystem functions have been studied more extensively in temperate and boreal ecosystems than in the tropics. Although tropical regions Abstract Respiration is instrumental for survival and growth of plants, but increasing costs of maintenance processes with warming have the potential to change the balance between photosynthetic carbon uptake and respiratory carbon release from leaves. Climate warming may cause substantial increases of leaf respiratory carbon fluxes, which would further impact the carbon balance of terrestrial vegetation. However, downregulation of respiratory physiology via thermal acclimation may mitigate this impact. We have conducted a meta-analysis with data collected from 43 independent studies to assess quantitatively the thermal acclimation capacity of leaf dark respiration to warming of terrestrial plant species from across the globe. In total, 282 temperature contrasts were included in the meta-analysis, representing 103 species of forbs, graminoids, shrubs, trees and lianas native to arctic, boreal, temperate and tropical ecosystems. Acclimation to warming was found to decrease respiration at a set temperature in the majority of the observations, regardless of the biome Communicated by Rowan Sage. Electronic supplementary materialThe online version of this article

Differential responses of ecosystem respiration components to experimental warming in a meadow grassland on the Tibetan Plateau

“…Our results indicate that warming eventually could cause R eco to become dominated by R plant , an idea that has been suggested in previous studies (Hicks Pries et al, 2015;Peng et al, 2014;Suseela and Dukes, 2013). The significant positive effects of experimental warming on AGB may be key to the result of increased R plant or R agb relative to R eco , even though plant respiration acclimates to warming (Lin et al, 2010;Slot and Kitajima, 2015;Way and Oren, 2010). Another possible explanation might be that the varied responses of the components of R eco to changes in soil temperature and moisture (Fig.…”

“…We further found larger increases in R agb in 2012 and 2013 compared with 2011 ( Fig. 2), which is in contrast to what one would expect if acclimation occurred (Atkin and Tjoelker, 2003;Slot and Kitajima, 2015). On the other hand, if growth were stimulated by warming (Fig.…”

Convergence in the temperature response of leaf respiration across biomes and plant functional types

“…In such ecosystems, reliance on a fixed Q 10 greatly overestimates annual leaf R, which in turn will result in underestimates of net primary productivity (NPP), as generally TBMs estimate NPP by subtraction of total canopy leaf R from modeled estimates of gross primary productivity (GPP). Though future model implementations that consider the extent to which leaf R acclimates to long-term changes in air T across the globe (24,25) will likely further improve how leaf R is represented in TBMs, our findings point to lower rates of modeled respiratory CO 2 releaseand thus possible higher rates of simulated NPP-at sites further away from the equator, compared with current model scenarios. As replacement of a fixed Q 10 formulation with our GPM is likely to have profound effects on estimates of global plant R and calculations of NPP, its adoption in ESMs will adjust projections of both contemporary and future carbon storage in vegetation.…”

“…We aim to significantly improve how the short-term R-T response is represented, and recognize this is one element of a complex and dynamic process. As leaf R is also impacted by acclimation to sustained changes in growth T, future modeling work will determine the effect of a more accurate short-term T response applied in concert with recent advances in modeling basal rates of leaf R (23) and longer-term (weeks to months) acclimation of R to changing growth Ts (24,25).…”

Influence of arbuscular mycorrhizal colonization on whole‐plant respiration and thermal acclimation of tropical tree seedlings

“…Thermal acclimation is a biochemical, physiological, or structural adjustment by an individual plant in response to a change in the temperature regime that results in a shift in the short‐term response to temperature. Acclimation to warming commonly results in down‐regulation of respiration rates at a given temperature (Slot and Kitajima 2015), such that acclimated plants experience lower respiratory carbon loss at their new temperature than nonacclimated plants (Atkin and Tjoelker 2003). Our understanding of respiratory responses remains limited for tropical species, particularly at the whole‐plant level.…”