Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 6 4 2009 10.5194/bg-6-615-2009 http://www.biogeosciences.net/6/615/2009/ http://www.biogeosciences.net/6/615/2009/bg-6-615-2009.html http://www.biogeosciences.net/6/615/2009/bg-6-615-2009.pdf 615 621 2009-04-17 Physical injury stimulates aerobic methane emissions from terrestrial plants Z.-P. Wang wangzp5@ibcas.ac.cn J. Gulledge J.-Q. Zheng W. Liu L.-H. Li X.-G. Han State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Xiangshan, Beijing 100093, China Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA Pew Center on Global Climate Change, 2101 Wilson Blvd., Arlington, Virginia, USA Physical injury is common in terrestrial plants as a result of grazing, harvesting, trampling, and extreme weather events. Previous studies demonstrated enhanced emission of non-microbial CH₄ under aerobic conditions from plant tissues when they were exposed to increasing UV radiation and temperature. Since physical injury is also a form of environmental stress, we sought to determine whether it would also affect CH₄ emissions from plants. Physical injury (cutting) stimulated CH₄ emission from fresh twigs of <i>Artemisia</i> species under aerobic conditions. More cutting resulted in more CH₄ emissions. Hypoxia also enhanced CH₄ emission from both uncut and cut <i>Artemisia frigida</i> twigs. Physical injury typically results in cell wall degradation, which may either stimulate formation of reactive oxygen species (ROS) or decrease scavenging of them. Increased ROS activity might explain increased CH₄ emission in response to physical injury and other forms of stress. There were significant differences in CH₄ emissions among 10 species of <i>Artemisia</i>, with some species emitting no detectable CH₄ under any circumstances. Consequently, CH₄ emissions may be species-dependent and therefore difficult to estimate in nature based on total plant biomass. Our results and those of previous studies suggest that a variety of environmental stresses stimulate CH₄ emission from a wide variety of plant species. Global change processes, including climate change, depletion of stratospheric ozone, increasing ground-level ozone, spread of plant pests, and land-use changes, could cause more stress in plants on a global scale, potentially stimulating more CH₄ emission globally. Beerling, D. J., Gardiner, T., Leggett, G., Mcleod, A., and Quick, W. P.: Missing methane emissions from leaves of terrestrial plants, Glob. Change Biol., 14, 1–6, 2008. Brüggemann, N., Meier, R., Steigner, D., Zimmer, I., Louis, S., and Schnitzler, J.-P.: Nonmicrobial aerobic methane emission from poplar shoot cultures under low-light conditions, New Phytol., doi:10.1111/j.1469-8137.2009.02797.x, 2009. Butenhoff, C. L. and Khalil, M. A. K.: Global methane emissions from terrestrial plants, Environ. Sci. Technol., 41, 4032–4037, 2007. Cao, G. M., Xu, X. L., Long, R. J., Wang, Q. L., Wang, C. T., Du, Y. G., and Zhao, X. Q.: Methane emissions by alpine plant communities in the Qinghai-Tibet Plateau, Biol. Lett.-UK, 4, 681–684, 2008. do Carmo, J. B., Keller, M., Dias, J. D., de Camargo, P. B., and Crill, P.: A source of methane from upland forests in the Brazilian Amazon, Geophys. Res. Lett., 33, L04809, doi:10.1029/2005GL025436, 2006. Chen, H. J. and Qualls, R. G.: Anaerobic metabolism in the roots of seedlings of the invasive exotic \textitLepidium latifolium, Environ. Exp. Bot., 50, 29–40, 2003. Cheng, G. P., Duan, X. W., Yang, B., Jiang, Y. M., Lu, W. J., Luo, Y. B., and Jiang, W. B.: Effect of hydroxyl radical on the scission of cellular wall polysaccharides in vitro of banana fruit at various ripening stages, Acta Physiol. Plant, 30, 257–263, 2008. Crawford, R. M. M. and Brandle, R.: Oxygen deprivative stress in a changing environment, J. Exp. Bot., 47, 145–159, 1996. Crutzen, P. J., Sanhueza, E., and Brenninkmeijer, C. A. M.: Methane production from mixed tropical savanna and forest vegetation in Venezuela, Atmos. Chem. Phys. Discuss., 6, 3093–3097, 2006. Drew, M. C.: Oxygen deficiency and root metabolism: injury and acclimation under hypoxia and anoxia, Ann. Rev. Plant Physiol. Plant Mole. Biol., 48, 223–250, 1997. Dueck, T. A., de Visser, R., Poorter, H., Persijn, S., Gorissen, A., de Visser, W., Schapendonk, A., Verhagen, J., Snel, J., Harren, F. J. M., Ngai, A. K. Y., Verstappen, F., Bouwmeester, H., Voesenek, L. A. C. J., and van der Werf, A.: No evidence for substantial aerobic methane emission by terrestrial plants: a $^13$C-labelling approach, New Phytol., 175, 29–35, 2007. Dueck, T. and van der Werf, A.: Are plants precursors for methane?, New Phytol., 178, 693–695, 2008. Ferretti, D. F., Miller, J. B., White, J. W. C., Lassey, K. R., Lowe, D. C., and Etheridge, D. M.: Stable isotopes provide revised global limits of aerobic methane emissions from plants, Atmos. Chem. Phys., 7, 237–241, 2007. Frankenberg, C., Meirink, J. F., van Weele, M., Platt, U., and Wagner, T.: Assessing methane emissions from global space-borne observations, Science, 308, 1010–1014, 2005. Frankenberg, C., Bergamaschi, P., Butz, A., Houweling, S., Meirink, J. F., Notholt, J., Petersen, A. K., Schrijver, H., Warneke, T., and Aben, I.: Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT, Geophys. Res. Lett., 35, L15811, doi:10.1029/2008GL034300, 2008. Fry, S. C.: Oxidative scission of plant cell wall polysaccharides by ascorbate-induced hydroxyl radicals, Biochem. J., 332, 507–515, 1998. Houweling, S., Röckmann, T., Aben, I., Keppler, F., Krol, M., Meirink, J. F., Dlugokencky, E. J., and Frankenberg, C.: Atmospheric constraints on global emissions of methane from plants, Geophys. Res. Lett., 33, L15821, doi:10.1029/2006GL026162, 2006. Keppler, F., Hamilton, J. T. G., Braß, M., and Röckmann, T.: Methane emissions from terrestrial plants under aerobic conditions, Nature, 439, 187–191, 2006. Keppler, F., Hamilton, J. T. G., McRoberts, W. C., Vigano, I., Braß, M., and Röckmann, T.: Methoxyl groups of plant pectin as a precursor of atmospheric methane: evidence from deuterium labelling studies, New Phytol., 178, 808–814, 2008. Kirschbaum, M. U. F., Bruhn, D., Etheridge, D. M., Evans, J. R., Farquhar, G. D., Gifford, R. M., Paul, K. I., and Winters, A. J.: A comment on the quantitative significance of aerobic methane release by plants, Funct. Plant Biol., 33, 521–530, 2006. Kirschbaum, M. U. F., Niinemets, U., Bruhn, D., and Winters, A. J.: How important is aerobic methane release by plants?, Functional Plant Science and Technology, 1, 138–145, 2007. Kirschbaum, M. U. F. and Walcroft, A.: No detectable aerobic methane efflux from plant material, nor from adsorption/desorption processes, Biogeosciences, 5, 1551–1558, 2008. Lin, K. H., Chao, P. Y., Yang, C. M., Cheng, W. C., Lo, H. F., and Chang, T. R.: The effects of flooding and drought stresses on the antioxidant constituents in sweet potato leaves, Bot. Stud., 47, 417–426, 2006. McLeod, A. R., Fry, S. C., Loake, G. J., Messenger, D. J., Reay, D. S., Smith, K. A., and Yun, B. W.: Ultraviolet radiation drives methane emissions from terrestrial plant pectins, New Phytol., 180, 124–132, 2008. Messenger, D. J., McLeod, A. R., and Fry, S. C.: The role of ultraviolet radiation, photosensitizers, reactive oxygen species and ester groups in mechanisms of methane formation from pectin, Plant Cell Environ., 32, 1–9, 2009. Miller, J. B., Gatti, L. V., d'Amelio, M. T. S., Crotwell, A. M., Dlugokencky, E. J., Bakwin, P., Artaxo, P., and Tans, P. P.: Airborne measurements indicate large methane emissions from the eastern Amazon basin, Geophys. Res. Lett., 34, L10809, doi:10.1029/2006GL029213, 2007. Nisbet, R. E. R., Fisher, R., Nimmo, R. H., Bendall, D. S., Crill, P. M., Gallego-Sala, A. V., Hornibrook, E. R. C., López-Juez, E., Lowry, D., Nisbet, P. B. R., Shuckburgh, E. F., Sriskantharajah, S., Howe, C. J., and Nisbet, E. G.: Emission of methane from plants, Proceedings of the Royal Society B: Biological Sciences, 276, 1347–1354, 2009. Parsons, A. J., Newton, P. C. D., Clark, H., and Kelliher, F. M.: Scaling methane emissions from vegetation, Trends Ecol. Evol., 21, 423–424, 2006. Sanhueza, E. and Donoso, L.: Methane emission from tropical savanna \textitTrachypogon sp. grasses, Atmos. Chem. Phys., 6, 5315–5319, 2006. SAS: SAS/STATk User's Guide Release 8.0 Cary, North Carolina, USA, 1999. Scandalios, J. G.: Molecular Biology of Free Radical Scavenging Systems, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York, 1992. Scandalios, J. G.: Oxygen stress and superoxide dismutases, Plant Physiol., 101, 7–12, 1993. Schiermeier, Q.: Methane finding baffles scientists, Nature, 439, 128–128, 2006. Schimel, J. P.: Plant transport and methane production as controls on methane flux from arctic wet meadow tundra, Biogeochemistry, 28, 183–200, 1995. Schweikert, C., Liszkay, A., and Schopfer, P.: Polysaccharide degradation by Fenton reaction- or peroxidase-generated hydroxyl radicals in isolated plant cell walls, Phytochemistry, 61, 31–35, 2002. Sinha, V., Williams, J., Crutzen, P. J., and Lelieveld, J.: Methane emissions from boreal and tropical forest ecosystems derived from in-situ measurements, Atmos. Chem. Phys. Discuss., 7, 14011–14039, 2007. Thompson, J. E., Legge, R. L., and Barber, R. F.: The role of free radicals in senescence and wounding, New Phytol., 105, 317–344, 1987. Vigano, I., van Weelden, H., Holzinger, R., Keppler, F., McLeod, A., and Röckmann, T.: Effect of UV radiation and temperature on the emission of methane from plant biomass and structural components, Biogeosciences, 5, 937–947, 2008. Wang, Z. P., Han, X. G., Li, L. H., Chen, Q. S., Duan, Y., and Cheng, W.: Methane emission from small wetlands and implications for semiarid region budgets, J. Geophys. Res., 110, D13304, doi:13310.11029/12004JD005548, 2005. Wang, Z. P., Han, X. G., Wang, G. G., Song, Y., and Gulledge, J.: Aerobic methane emission from plants in the Inner Mongolia steppe, Environ. Sci. Technol., 42, 62–68, 2008.