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Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth’s surface. This study received support from the following sources: US National Science Foundation (NSF) DEB-1655759 (A.E.Z.); US NSF DEB-2149151 (A.E.Z.); US NSF DEB-1713502 (M.A.); US NSF DEB-1713435 (M.A.); US NSF DEB-1647502 (N.A.B.); US NSF DEB-1546686 (G.G.); US NSF DEB-1831952 (G.G.); George Washington University (A.E.Z.); USDA Forest Service (G.G.); Centre College Faculty Development Funds (M.L.G.); Australia Terrestrial Ecosystem Research Network National Collaborative Research Infrastructure Strategy (P.R.G., M.K., M.L., M.M.B., R.P.S., J.S., L.B.H., M.N., S.M.P., T.J.W., and S.K.A.); Royal Society-FCDO Africa Capacity Building Initiative (C.L.P., G.W.Q., S.A.-B., K.B., F.E.O., and M.P.R.); New Phytologist Foundation (A.T.A.); Fondecyt grant 1160329 (C.D.); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brasil (CAPES) (E.v.d.B., A.S.Mou., R.F.M., F.F.S., T.M.C.-S., R.S.O., and A.M.D.); Department of Ecology and Conservation of the Federal University of Lavras (T.M.C.-S.); CNPq (E.v.d.B. and R.S.O.); FAPEMIG (E.v.d.B.); Australian Academy of Science 2017 Thomas Davies Research Grant (J.R.P.); Australian Research Council DP160103765 (W.K.C., J.R.P., and A.E.Z.); UK National Environment Research Council NE/L000016/1 (L.A.A.); Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil NERC - FAPESP 19/07773-1 (R.S.O. and A.M.D.); Environment Research and Technology Development Fund ERTDF, JPMEERF15S11420 of the Environmental Restoration and Conservation Agency of Japan (A.S.Mor. and K.O.); COLCIENCIAS no. FP44842-046-2017 (J.M.P.); Spanish government PID2019-110521GB-I00 (J.Pe., G.P., and R.O.); Catalan government grant SGR 2017-1005 (J.Pe., G.P., and R.O.); Fundación Ramón Areces ELEMENTAL-CLIMATE (J.Pe., G.P., and R.O.); National Agency for the Promotion of Research, Technological Development and Innovation, Scientific and Technological Research Project 2018-01561 PICT 2018-01561 (F.P.T.); ANID PIA/BASAL FB210006 (A.Fa.); Millennium Science Initiative Program NCN2021-050 (A.Fa.); iDiv German Research Foundation DFG–FZT 118, 202548816 (N.E.); and European Research Council Horizon 2020 research and innovation program no. 677232 (N.E.).

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)—even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface.

Growth chamber experiments were conducted with seedless cucumber cv. Odeon to examine the effect of night temperature on photosynthesis and growth with compensation possibilities of daytime irradiance level. Further, the effects of night temperature and the level of daytime irradiance on carbohydrate composition in different plant parts were also assessed with high performance liquid chromatography (HPLC). Daily average temperature was mainly responsible for the growth of cucumber seedling by increasing the height, leaf number, total leaf area and total dry weight. It enhances the potential of lowering night temperature in combination with high day temperature. Lowering night temperature from 22 °C to 14 °C reduced almost 34% growth as dry matter production. As long as the daily mean temperature is equal, the split night temperature had no effect on daily net photosynthesis, height; leaf area and plant dry weight. Increasing level of irradiance increased the plant’s daily net photosynthesis and the magnitude of increment was significantly high at low night temperature than at high night temperature. At low night temperature (14 °C), net photosynthesis was doubled when light intensity was increased from 200 to 400 μmol m-2 s-1. This was reflected in the total dry weight of the plants as well. The dry matter production of cucumber seedling increased almost 30% at low night temperature (14 °C) and 7% at high night temperature (22 °C) when light intensity was doubled. This indicated the potential of irradiance on compensation of losses caused by low temperature although, it will be extra energy costs related to increased light level if that has to be done by artificial lighting. Carbohydrate profiling revealed that the total carbohydrate content was significantly affected by irradiance level than temperature. Total carbohydrate concentration was increased by 8% at low night temperature (14 °C) and 20% at high light intensity (400 μmol m-2 s-1). Among the different plant parts analyzed, the total carbohydrate content was significantly high in stem in all temperature and irradiance combinations. However, night temperature or daytime irradiance did not affect the proportion of total carbohydrate partitioned between plant parts. M-PV

This study assesses relative growth rates and carbohydrate contents of three lichen species under different temperature and humidity regimes in a short-term growth chamber experiment. Representatives from three functional groups: chlorolichens (Parmelia sulcata; green algal), cyanolichens (Peltigera canina; cyanobacterial) and cephalolichens (Peltigera aphthosa; green alga + cyanobacteria) were cultivated for 14 days (150 µmol photon m-2 s-1; 12 h photoperiod) at four temperature regimes (28/23 °C, 20/15 °C, 13/8 °C, and 6/1 °C; day/night temperatures) and two hydration regimes (12 h day-time hydration; 12 h day-time + 12 h night-time hydration). These lichens showed much higher growth than earlier reported, particularly at 13/8 °C. A two-way ANOVA with temperature, humidity regimes as factors and specific thallus mass as a co-variate explained 57.8, 53.2 and 38.1 % of the variation in RGR for P. aphthosa, P. canina and P. sulcata, respectively. Significantly higher relative biomass (RGR) as well as thallus area growth rates (RTAGR) were recorded when the thalli were hydrated day and night compared to hydration in day-time only in all species. Chronic photoinhibition was substantial in P. apthosa and P. canina when kept at lowest temperature regimes and also for the thalli kept dry at night, whereas P. sulcata was photoinhibited at the highest temperature for thalli kept dry at night. Strong, positive linear regressions occurred between RGR and maximal PSII efficiency (Fv/Fm) in all species. Metabolic activity at night improved recovery of photoinhibition and/or may enhance the conversion rate of photosynthates into thallus growth. Moreover, the carbohydrate pools in all the species were measured through HPLC. Unlike the dynamic growth patterns, carbohydrate concentrations varied little with temperature and humidity regimes. After 14 days cultivation, total carbohydrate pool decreased in P. aphthosa and P. canina, but slightly increased in P. sulcata. Mannitol occurred in all the species. Quantitatively, the largest carbohydrate pool was mannitol, glucose and arabitol for P. aphthosa, P. canina and P. sulcata, respectively. The RGR was significantly correlated with photobiont carbohydrate in all species. M-ECOL