The Effect of the Foresummer Drought on Carbon Exchange in Subalpine Meadows

Springer Science and Business Media LLC - Tập 18 - Trang 533-545 - 2015
Lindsey L. Sloat1,2, Amanda N. Henderson1,2, Christine Lamanna2,3, Brian J. Enquist1,2,4
1Department of Ecology and Evolutionary Biology, The University of Arizona, Tucson, USA
2The Rocky Mountain Biological Laboratory, Gothic, USA
3World Agroforestry Centre, United Nations Ave., Nairobi, Kenya
4The Santa Fe Institute, Santa Fe, USA

Tóm tắt

Climate in subalpine meadows of the Rocky Mountains can be characterized by an early (foresummer) drought that occurs after snowmelt (May) and lasts until the start of the summer monsoon season (July). Climate change models predict an increase in the length and severity of this dry period due to earlier snowmelt dates, rising air temperatures, and shifts in the start and/or intensity of the North American monsoon. However, it is unknown how changes in the severity of this early season dry period will affect ecosystem carbon exchange. To address the importance of early season drought, we combined a watering manipulation with 11 years of ecosystem carbon exchange data across an elevational gradient at the Rocky Mountain Biological Laboratory in Gothic, Colorado. Long-term trends reveal that earlier snowmelt dates lead to a decrease in net ecosystem productivity (NEP), in part because of the positive effect on early growing season drought conditions. Manipulating the strength of the foresummer drought by watering revealed that the timing of growing season precipitation is more important than the total amount for determining cumulative NEP. The strength of the foresummer drought did not significantly impact ecosystem respiration rates, but plants that experienced a strong foresummer drought exhibited more water stress, and lower instantaneous rates of NEP, even during the rainy season. Our results highlight the central role of the foresummer drought in determining rates of carbon exchange throughout the growing season, and the potential for an increasingly negative balance of carbon in subalpine meadows under future climate change.

Tài liệu tham khảo

Adams DK, Comrie AC. 1997. The North American monsoon. Bull Am Meteorol Soc 78:2197–213.

Angert A, Biraud S, Bonfils C, Henning CC, Buermann W, Pinzon J, Tucker CJ, Fung I. 2005. Drier summers cancel out the CO2 uptake enhancement induced by warmer springs. Proc Natl Acad Sci USA 102:10823–7.

Arnone JA, Obrist D. 2003. A large daylight geodesic dome for quantification of whole-ecosystem CO2 and water vapour fluxes in arid shrublands. J Arid Environ 55:629–43.

Begon M, Townsend C, Harper J. 2009. Ecology: from individuals to ecosystems. New York: Wiley.

Beier C, Beierkuhnlein C, Wohlgemuth T, Penuelas J, Emmett B, Körner C, de Boeck H, Christensen JH, Leuzinger S, Janssens IA, Hansen K, Arnone J. 2012. Precipitation manipulation experiments—challenges and recommendations for the future. Ecol Lett 15:899–911.

Berdanier AB, Klein JA. 2011. Growing season length and soil moisture interactively constrain high elevation aboveground net primary production. Ecosystems 14:963–74.

Biasutti M, Sobel AH. 2009. Delayed Sahel rainfall and global seasonal cycle in a warmer climate. Geophys Res Lett 36:L23707.

Bryant JA, Lamanna C, Morlon H, Kerkhoff AJ, Enquist BJ, Green JL. 2008. Microbes on mountainsides: contrasting elevational patterns of bacterial and plant diversity. PNAS 105:11505–11.

Diffenbaugh NS, Scherer M, Ashfaq M. 2013. Response of snow-dependent hydrologic extremes to continued global warming. Nat Clim Chang 3:379–84.

Dunne JA, Harte J, Taylor KJ. 2003. Subalpine meadow flowering phenology responses to climate change: integrating experimental and gradient methods. Ecol Monogr 73:69–86.

Dunne JA, Saleska SR, Fischer ML, Harte J. 2004. Integrating experimental and gradient methods in ecological climate change research. Ecology 85:904–16.

Euskirchen ES, McGuire AD, Kicklighter DW, Zhuang Q, Clein JS, Dargaville RJ, Dye DG, Kimball JS, McDonald KC, Melillo JM, Romanovsky VE, Smith NV. 2006. Importance of recent shifts in soil thermal dynamics on growing season length, productivity, and carbon sequestration in terrestrial high-latitude ecosystems. Glob Chang Biol 12:731–50.

Farquhar GD, Sharkey TD. 1982. Stomatal conductance and photosynthesis. Annu Rev Plant Physiol 33:317–45.

Harte J, Saleska S, Shih T. 2006. Shifts in plant dominance control carbon-cycle responses to experimental warming and widespread drought. Environ Res Lett 1:014001.

Harte J, Shaw R. 1995. Experiment shifting dominance within a montane vegetation community: results of a climate-warming experiment. Science 267:876–80.

Higgins RW, Shi W. 2001. Intercomparison of the principal modes of interannual and intraseasonal variability of the North American monsoon system. J Clim 14:403–17.

Higgins RW, Yao Y, Wang XL. 1997. Influence of the North American monsoon system on the U.S. Summer precipitation regime. J Clim 10:2600–22.

Hu J, Moore DJP, Burns SP, Monson RK. 2010. Longer growing seasons lead to less carbon sequestration by a subalpine forest. Glob Chang Biol 16:771–83.

Huxman TE, Snyder KA, Tissue D, Leffler AJ, Ogle K, Pockman WT, Sandquist DR, Potts DL, Schwinning S. 2004. Precipitation pulses and carbon fluxes in semiarid and arid ecosystems. Oecologia 141:254–68.

Iler AM, Høye TT, Inouye DW, Schmidt NM. 2013a. Long-term trends mask variation in the direction and magnitude of short-term phenological shifts. Am J Bot 100:1398–406.

Iler AM, Høye TT, Inouye DW, Schmidt NM. 2013b. Nonlinear flowering responses to climate: are species approaching their limits of phenological change? Philos Trans R Soc Lond B Biol Sci 368:20120489.

Iler AM, Inouye DW. 2013. Effects of climate change on mast-flowering cues in a clonal montane herb, Veratrum tenuipetalum (Melanthiaceae). Am J Bot 100:519–25.

IPCC. 2013. Working group I contribution to the IPCC fifth assessment report on climate change 2013.

Jasoni RL, Smith SD, Arnone JA. 2005. Net ecosystem CO2 exchange in Mojave Desert shrublands during the eighth year of exposure to elevated CO2. Glob Chang Biol 11:749–56.

Johnston B, Huckaby L, Hughes T, Pecor J. 2001. Ecological types of the Upper Gunnison Basin. Serv Tech Rep R2-RR-2001.

Kellner O, Niyogi D. 2014. Assessing drought vulnerability of agricultural production systems in context of the 2012 drought. J Anim Sci 92:2811–22.

Kirschbaum M, Eamus D, Gifford R, Roxburgh S, Sands PJ. 2001. Definitions of some ecological terms commonly used in carbon accounting. Coop Reserach Cent Carbon Accounting, Canberra 2001:2–5.

Kreyling J, Jentsch A, Beier C. 2013. Beyond realism in climate change experiments: gradient approaches identify thresholds and tipping points. Ecol Lett 17:125-e1.

Lamanna CA. 2012. The structure and function of subalpine ecosystems in the face of climate change. http://arizona.openrepository.com/arizona/bitstream/10150/228495/1/azu_etd_12118_sip1_m.pdf.

Langenheim JH. 1962. Vegetation and environmental patterns in the Crested Butte Area, Gunnison County, Colorado. Ecol Soc Am 32:249–85.

Patrick L, Cable J, Potts D, Ignace D, Barron-Gafford G, Griffith A, Alpert H, Van Gestel N, Robertson T, Huxman TE, Zak J, Loik ME, Tissue D. 2007. Effects of an increase in summer precipitation on leaf, soil, and ecosystem fluxes of CO2 and H2O in a sotol grassland in Big Bend National Park, Texas. Oecologia 151:704–18.

Poore RE, Lamanna CA, Ebersole JJ, Enquist BJ. 2009. Controls on radial growth of mountain big sagebrush and implications for climate change. West North Am Nat 69:556–62.

Potts DL, Huxman TE, Cable JM, English NB, Ignace DD, Eilts JA, Mason MJ, Weltzin JF, Williams DG. 2006. Antecedent moisture and seasonal precipitation influence the response of canopy-scale carbon and water exchange to rainfall pulses in a semi-arid grassland. New Phytol 170:849–60.

Price MV, Waser NM. 1998. Effects of experimental warming on plant reproductive phenology in a subalpine meadow. Ecology 79:1261–71.

Rauscher SA, Giorgi F, Seth A, Diffenbaugh NS. 2008. Extension and Intensification of the Meso-American mid-summer drought in the twenty-first century. Clim Dyn 31:551–71.

Reay DS, Hewitt CN, Smith KA, Grace J. 2007. Greenhouse gas sinks. Oxfordshire: CABI.

Ryan MG, Law BE. 2005. Interpreting, measuring, and modelling soil respiration. Biogeochemistry 73:3–27.

Saleska SR, Harte J, Torn MS. 1999. The effect of experimental ecosystem warming on CO2 fluxes in a montane meadow. Glob Chang Biol 5:125–41.

Saleska SR, Shaw MR, Fischer ML, Dunne JA, Still CJ, Holman ML, Harte J. 2002. Plant community composition mediates both large transient decline and predicted long-term recovery of soil carbon under climate warming. Global Biogeochem Cycles 16:3-1.

Schwalm CR, Williams CA, Schaefer K, Baldocchi D, Black TA, Goldstein AH, Law BE, Oechel WC, Paw UKT, Scott RL. 2012. Reduction in carbon uptake during turn of the century drought in western North America. Nat Geosci 5:551–6.

Seth A, Rauscher SA, Rojas M, Giannini A, Camargo S. 2011. Enhanced spring convective barrier for monsoons in a warmer world? Clim Change 104:403–14.

Tezara W, Mitchell VJ, Driscoll SD, Lawlor DW. 1999. Water stress inhibits plant photosynthesis by decreasing coupling factor and ATP. Nature 401:914–17.

Thompson RM, Beardall J, Beringer J, Grace M, Sardina P. 2014. Moving beyond methods: the need for a diverse programme in climate change research. Ecol Lett 17:125.

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Springer Science and Business Media LLC

Tập 18

533-545

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