Chinese Journal of Plant Ecology >
Drought stress reduces the carbon accumulation of the Leymus chinensis steppe in Inner Mongolia, China
Received date: 2009-11-18
Accepted date: 2009-11-18
Online published: 2010-09-28
Aims Droughts are common in arid and semiarid regions and affect the capacity of carbon sequestration of grassland ecosystems by influencing the process of ecosystem carbon cycling. We analyzed the continuous measurements of ecosystem CO2 fluxes during three growing seasons (May-September) over a Leymus chinensis steppe in Inner Mongolia in order to examine the effect of drought stress on carbon accumulation of this grassland ecosystem.
Methods We used the eddy covariance technique to measure CO2 fluxes during the 2004-2006 growing seasons. Only 126 and 215 mm precipitation fell during the 2005 and 2006 growing seasons, respectively, far less than normal (in 2004, 364 mm); therefore, the steppe was in an extreme drought condition.
Important findings Maxima for gross primary productivity (GPP) and ecosystem respiration (Re) were 4.89 and 1.99 g C·m-2·d-1, respectively, in the 2004 growing season (normal year). However, in drought years, GPP and Re were 1.53-3.01 and 1.38-1.77 g C·m-2·d-1, respectively. GPP and Re in the drought years decreased by 68% and 11%, respectively, compared with the normal year. Accumulated GPP and Re were 294 and 180 g C·m-2, respectively, during the growing season in 2004 and 102-123 and 132-158 g C·m-2, respectively, in drought years. Accumulated GPP and Re decreased 58%-65% and 12%-27%, respectively, in drought years compared with those of the normal year. The slope of the curve in the sensitivity for Re to Ts (Vant’Hoff type) reached its maximum at θ = 0.16-0.17 m3·m-3; below or above this value of θ, the sensitivity of Re to Ts decreases. GPP and Re decline under drought stress conditions, with GPP having a larger decline. Long-term and continuous drought reduced C-accumulation and resulted in the steppe ecosystem switching from a carbon sink in typical years to a carbon source in drought years.
HAO Yan-Bin, WANG Yan-Fen, CUI Xiao-Yong . Drought stress reduces the carbon accumulation of the Leymus chinensis steppe in Inner Mongolia, China[J]. Chinese Journal of Plant Ecology, 2010 , 34(8) : 898 -906 . DOI: 10.3773/j.issn.1005-264x.2010.08.002
| [1] | Atkin OK, Tjoelker MG (2003). Thermal acclimation and the dynamic response of plant respiration to temperature. Trends in Plant Science, 8, 343-351. |
| [2] | Baldocchi DD (2003). Assessing ecosystem carbon balance: problems and prospects of the eddy covariance technique. Global Change Biology, 9, 478-492. |
| [3] | Bhupinderpal-Singh, Nordgren A, Ottossonlofvenius M, Hogberg MN, Mellander PE, Hogberg P (2003). Tree root and soil heterotrophic respiration as revealed by girdling of boreal Scots pine forest: extending observation beyond the first year. Plant, Cell & Environment, 26, 1287-1296. |
| [4] | Cox PM, Betts RA, Jones CD, Spall SA, Totterdell IJ (2000). Acceleration of global warming due to carbon-cycle feedbacks in a coupled climate model. Nature, 408, 184-187. |
| [5] | Curiel Yuste J, Janssens IA, Carrara A, Meiresonne L, Ceulemans R (2003). Interactive effects of temperature and precipitation on soil respiration in a temperate maritime pine forest. Tree Physiology, 23, 1263-1270. |
| [6] | Davidson EA, Delc E, Boone RD (1998). Soil water content and temperature as independent or confounded factors controlling soil respiration in a temperate mixed hardwood forest. Global Change Biology, 4, 217-227. |
| [7] | Easterling DR, Meehl GA, Parmesan C, Changnon SA, Karl TR, Mearns LO (2000). Climate extremes: observations, modeling, and impacts. Science, 289, 2068-2074. |
| [8] | Falge E, Baldocchi DD, Richard O, Anthoni P, Aubinet M, Bernhofer C, Burba G, Ceulemans R, Clement R, Dolman H, Granier A, Gross P, Grünwald T, Hollinger D (2001). Gap filling strategies for defensible annual sums of net ecosystem exchange. Agricultural and Forest Meteorology, 107, 43-69. |
| [9] | Falge E, Pilegaard K, Aubinet M, Bernhofer C, Clement R, Granier A, Kowalski AS, Moors EJ, Pileqarrd K, Rannik U, Rebmann C (2003). A model-based study of carbon fluxes at ten European forest sites. In: Valentinin R ed. Ecological Studies Vol.163, Fluxes of Carbon, Water and Energy of European Forest. Springer-Verlag, Berlin.. |
| [10] | Goulden ML, Munger JW, Fan SM, Daube BC, Wofsy SC (1996). Measurements of carbon sequestration by long-term eddy covariance: methods and a critical evaluation of accuracy. Global Change Biology, 2, 169-182. |
| [11] | Granier A, Reichstein M, Breda N, Janssens IA, Falge E, Ciais P, Grünwald T, Aubinet M, Berbigier P, Bernhofer C, Buchmann N, Facini O, Grassi G (2007). Evidence for soil water control on carbon and water dynamics in European forests during the extremely dry year: 2003. Agricultural and Forest Meteorology, 143, 123-145. |
| [12] | Hartely IP, Armstrong AF, Murthy R, Barron-Gafford G, Ineson P, Atkin OK (2006). The dependence of respiration on photosynthetic substrate supply and temperature: integrating leaf, soil and ecosystem measurements. Global Change Biology, 12, 1954-1968. |
| [13] | H?gberg P, Nordgren A, Buchmann N, Taylor AF, H?gberg MN, Nyberg G, Ottosson-L?fvenius M, Read DJ (2001). Large-scale forest girdling shows that current photosynthesis drives soil respiration. Nature, 411, 789-792. |
| [14] | Houghton JT, Ding Y, Griggs DJ, Noguer M, van der Linden PJ, Dai X, Maskell K, Johnson CA (2001) Climate Change 2001: The Scientific Basis: Contribution of Working Group 1 to the Third Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK. |
| [15] | Hao Y, Wang Y, Mei XR, Huang X, Cui XY, Zhou XQ, Niu HS (2008). CO2, H2O and energy exchange of an Inner Mongolia steppe ecosystem during a dry and wet year. Acta Oecologia, 32, 133-143. |
| [16] | Huang XZ (黄祥忠), Hao YB (郝彦宾), Wang YF (王艳芬), Zhou XQ (周小奇), Han X (韩喜), He JJ (贺俊杰) (2006). Impact of extreme drought on the ecosystem exchange from Leymus chinensis steppe in Xilin River Basin, China. Journal of Plant Ecology (Chinese Version) (植物生态学报) 30, 894-900. (in Chinese with English abstract) |
| [17] | Ilstedt U, Nordgren A, Malmer A (2001). Optimum soil water for soil respiration before and after amendment with glucose in humid tropical acrisols and a boreal mor layer. Soil Biology and Biochemistry, 32, 1591-1599. |
| [18] | IPCC (Intergovernmental Panel on Climate Change) (2007). Fourth Assessment Report of Working Group III: Summary for Policymakers. Cambridge University Press, Cambridge, UK. |
| [19] | Kljun N, Black TA, Griffis TJ, Barr AG, Gaumont-Guay D, Barr AG, Gaumont-Guay D, Morgenstern K, McCaughey JH, Nesic Z (2006). Response of net ecosystem productivity of three boreal forest stands to drought. Ecosystems, 9, 1128-1144. |
| [20] | Krishnan P, Black TA, Grant NJ, Barr AG, Hogg TH, Jassal RS, Morgenstern K (2006). Impact of changing soil moisture distribution on net ecosystem productivity of a boreal aspen forest during and following drought. Agricultural and Forest Meteorology, 139, 208-223. |
| [21] | Kutsch LW, Staack A, W?tzel J, Middelhoff U, Kappen L (2001). Field measurements of root respiration and total soil respiration in an alder forest. New Phytologist, 150, 157-168. |
| [22] | Liu X, Wan S, Su B, Hui D, Luo Y (2002). Response of soil CO2 efflux to water manipulation in a tallgrass prairie ecosystem. Plant and Soil, 240, 213-233. |
| [23] | Luo Y, Wan S, Hui D, Wallace L (2001). Acclimatization of soil respiration to warming in a tallgrass prairie. Nature, 413, 622-625. |
| [24] | Mikan CJ, Schimel JP, Doyle AP (2002). Temperature controls of microbial respiration in arctic tundra soils above and below freezing. Soil Biology and Biochemistry, 34, 1785-1795. |
| [25] | Palmroth S, Maier CA, McCarthy HR, Oishi AC, Kim HS, Johnsen KH, Katul GG, Oren R (2005). Contrasting responses to drought of forest floor CO2 efflux in a Loblolly pine plantation and a nearby Oak-Hickory forest. Global Change Biology, 11, 421-434. |
| [26] | Rachhpal SJ, Black TA, Michael DN, Gaumont-Guay D, Nesic Z (2008). Effect of soil water stress on soil respiration and its temperature sensitivity in an 18-year-old temperate Douglas-fir stand. Global Change Biology, 14, 1-14. |
| [27] | Reich PB, Walters MB, Ellsworth DS (1997). From tropics to tundra: global convergence in plant functioning. Proceedings of the National Academy of Sciences of the United States of America, 94, 13730-13734. |
| [28] | Reichstein M, Tenhunen JD, Ourcival JM, Rambal S, Miglietta F, Peressotti A, Pecchiari M, Tirone G, Valentini R (2003). Severe drought effects on ecosystem CO2 and H2O fluxes at three Mediterranean sites: revision of current hypothesis? Global Change Biology, 8, 999-1017. |
| [29] | Savage KE, Davidson EA (2001). Interannual variation of soil respiration in two New England forests. Global Biogeochemical Cycles, 15, 337-350. |
| [30] | Thierron V, Laudelout H (1996). Contribution of root respiration to total soil CO2 efflux from the soil of a deciduous forest. Canadian Journal of Forest Research, 26, 1142-1148. |
| [31] | Trenberth KE (1999) Conceptual framework for changes of extremes of the hydrological cycle with climate change. Climatic Change, 42, 327-339. |
| [32] | Van’t Hoff JH (1898). Lectures on Theoretical and Physical Chemistry. Part I. Chemical Dynamics. Edward Arnold, London. |
| [33] | Wang WQ (王维强), Ge QS (葛全胜) (1993). Greenhouse effect’s impact on China’s social economic development. Science and Technology Review (科技导报), (3), 59-61. (in Chinese) |
| [34] | Xu L, Baldocchi DD (2004). Seasonal variation in carbon dioxide exchange over Mediterranean annual grassland in California. Agricultural and Forest Meteorology, 1232, 79-96. |
| [35] | Xu M, Qi Y (2001). Spatial and seasonal variations of Q10 determined by soil respiration measurements at a Sierra Nevadan forest. Global Biogeochemical Cycles, 15, 687-697. |
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