温度和水分对中亚热带人工林生态系统呼吸的调控作用

doi:10.11849/zrzyxb.2012.12.007

摘要/Abstract

摘要：

全球气候变化导致的降水格局改变影响陆地生态系统碳收支状况。陆地生态系统所固定的碳主要通过呼吸作用返回到大气中,而温度和水分是调节生态系统呼吸的重要因素。ChinaFLUX千烟洲中亚热带人工林通量站夏季雨热不同季而造成的季节性干旱为探讨温度和水分对生态系统呼吸的调控作用提供了天然的试验条件。研究利用该生态系统2003-2010年涡度相关和常规气象数据,阐述了生态系统呼吸对温度和土壤含水量的响应特征,对比分析了只考虑温度与同时考虑温度和土壤含水量对生态系统呼吸的季节模式和年呼吸量的影响。研究表明,生态系统呼吸的季节变异主要受土壤温度的控制,呈现指数响应特征。但是,在干旱胁迫条件下,土壤含水量对生态系统呼吸的季节变异起到明显的调控作用。参考温度下的生态系统呼吸(R_ref)明显受土壤含水量的影响。生态系统年呼吸量为1 289.4±73.9 gC·m^-2·a^-1,两类模型的估算结果没有显著差异。但是在生态系统的季节变异上,两类模型估算存在显著差异,同时考虑温度与土壤含水量的模型更适合模拟遭受干旱胁迫的生态系统呼吸。

关键词: 生态系统呼吸, 温度, 土壤含水量, 季节变异, 温度敏感性

Abstract:

The carbon balance has been affected by altered precipitation patterns caused by global climate changes. The carbon sequestrated by terrestrial ecosystems returns to the atmosphere mainly through respiration, of which temperature and water are two essential factors in regulating ecosystem respiration (R_eco). Seasonal drought caused by the imbalance of heat and rain provides natural experimental conditions to investigate the regulation of temperature and water on ecosystem respiration in the ChinaFLUX Qianyanzhou subtropical plantation. Based on the eddy covariance and conventional meteorological data collected from 2003 to 2010, this study analyzed the response of ecosystem respiration to temperature and soil water content, and explored the effects of temperature or both temperature and soil water content on ecosystem respiration seasonality and annual respiration. The study showed that the seasonal variations of ecosystem respiration were mainly controlled by soil temperature, and R_eco was an exponential function of soil temperature. Only under drought condition can soil water content play a significant role in regulation. With only temperature taken into account, the ecosystem respiration rate at the reference temperature (R_ref) was significantly affected by soil water content; while with temperature and soil water content taken into account, the ecosystem respiration under reference temperature was not affected by soil water content. There was no evident difference between considering temperature alone and both temperature and soil water content, the ecosystem respiration amount was 1289.4±73.9 g C·m^-2·a^-1. But the seasonal variations of ecosystem respiration had significant differences between 2003 and 2010 whether a seasonal drought existed or not.

Key words: respiration, temperature, soil water content, seasonal variation, Q₁₀

中图分类号:

Q148

张舒, 申双和, 温学发, 张心昱, 孙晓敏, 王辉民. 温度和水分对中亚热带人工林生态系统呼吸的调控作用[J]. 自然资源学报, 2012, 27(12): 2057-2070.

ZHANG Shu, SHEN Shuang-he, WEN Xue-fa, ZHANG Xin-yu, SUN Xiao-min, WANG Hui-min. The Regulation of Soil Temperature and Water on Ecosystem Respiration of a Subtropical Plantation under the Seasonal Drought[J]. JOURNAL OF NATURAL RESOURCES, 2012, 27(12): 2057-2070.

参考文献

[1] 于贵瑞, 孙晓敏. 陆地生态系统通量观测的原理与方法[M]. 北京: 高等教育出版社, 2006: 3-5.[YU Gui-rui, SUN Xiao-min. Principles of Flux Measurement in Terrestrial Ecosystems. Beijing: Higher Education Press, 2006: 3-5.]

[2] Raich J W, Schlesinger W H. The global carbon dioxide flux in soil respiration and its relationship to vegetation and climate [J]. Tellus B, 1992, 44(2): 81-99.

[3] Fernandez I J, Son Y, Kraske C R, et al. Soil carbon dioxide characteristics under different forest types and after harvest [J]. Soil Science Society of America Journal, 1993, 57: 1115-1121.

[4] Meehl G A, Tebaldi C. More intense, more frequent, and longer lasting heat waves in the 21st century [J]. Science, 2004, 305(5686): 994.

[5] Baldocchi D D. Breathing of the terrestrial biosphere: Lessons learned from a global network of carbon dioxide flux measurement systems [J]. Australian Journal of Botany, 2008, 56(1): 1-26.

[6] Baldocchi D D. Assessing the eddy covariance technique for evaluating carbon dioxide exchange rates of ecosystems: Past, present and future [J]. Global Change Biology, 2003, 9(4): 479-492.

[7] Yu G R, Wen X F, Sun X M, et al. Overview of ChinaFLUX and evaluation of its eddy covariance measurement [J]. Agricultural and Forest Meteorology, 2006, 137(3/4): 125-137.

[8] Wen X F, Yu G R, Sun X M, et al. Soil moisture effect on the temperature dependence of ecosystem respiration in a subtropical Pinus plantation of southeastern China [J]. Agricultural and Forest Meteorology, 2006, 137(3/4): 166-175.

[9] Zhang W J, Wang H M, Yang F T, et al. Underestimated effects of low temperature during early growing season on carbon sequestration of a subtropical coniferous plantation [J]. Biogeosciences, 2011, 8: 1667-1678.

[10] Reichstein M, Tenhunen J D, Roupsard O, et al. Severe drought effects on ecosystem CO₂ and H₂O fluxes at three Mediterranean evergreen sites: Revision of current hypotheses? [J] Global Change Biology, 2002, 8(10): 999-1017.

[11] 杨建伟, 梁宗锁, 韩蕊莲, 等. 不同土壤水分含量对4个树种WUE的影响[J]. 西北林学院学报, 2004, 19(1): 9-13.[YANG Jian-wei, LIANG Zong-suo, HAN Rui-lian, et al. Water use efficiency of four species under the different soil water content. Journal of Northwest Forestry University, 2004, 19(1): 9-13.]

[12] 黄祥忠, 郝彦宾, 王艳芬, 等. 极端干旱条件下锡林河流域羊草草原净生态系统碳交换特征[J]. 植物生态学报, 2006, 30(6): 894-900.[HUANG Xiang-zhong, HAO Yan-bin, WANG Yan-fen, et al. Impact of extreme drought on net ecosystem exchange from lemus chinensis steppe in Xilin River basin, China. Journal of Plant Ecology, 2006, 30(6): 894-900.]

[13] Yu G R, Wen X F, Li Q K, et al. Seasonal patterns and environmental control of ecosystem respiration in subtropical and temperate forests in China [J]. Science in China Series D: Earth Sciences, 2005, 48: 93-105.

[14] Barford C C, Wofsy S C, Goulden M L, et al. Factors controlling long- and short-term sequestration of atmospheric CO₂ in a mid-latitude forest [J]. Science, 2001, 294(5547): 1688.

[15] Baldocchi D D, Vogel C A, Hall B. Seasonal variation of carbon dioxide exchange rates above and below a boreal jack pine forest [J]. Agricultural and Forest Meteorology, 1997, 83(1/2): 147-170.

[16] Black T A, Hartog G, Neumann H, et al. Annual cycles of water vapour and carbon dioxide fluxes in and above a boreal aspen forest [J]. Global Change Biology, 1996, 2(3): 219-229.

[17] Goulden M L, Munger J W, Fan S M, et al. Exchange of carbon dioxide by a deciduous forest: Response to interannual climate variability [J]. Science, 1996, 271(5255): 1576.

[18] Greco S, Baldocchi D D. Seasonal variations of CO₂ and water vapour exchange rates over a temperate deciduous forest [J]. Global Change Biology, 1996, 2(3): 183-197.

[19] Aubinet M, Chermanne B, Vandenhaute M, et al. Long term carbon dioxide exchange above a mixed forest in the Belgian Ardennes [J]. Agricultural and Forest Meteorology, 2001, 108(4): 293-315.

[20] Lloyd J, Taylor J A. On the temperature-dependence of soil respiration [J]. Functional Ecology, 1994, 8(3): 315-323.

[21] Hollinger D Y, Kelliher F M, Byers J N, et al. Carbon dioxide exchange between an undisturbed old-growth temperate forest and the atmsphere[J]. Ecology, 1994, 75(1): 134-150.

[22] Tjoelker M G, Oleksyn J, Reich P B. Modelling respiration of vegetation: Evidence for a general temperature-dependent Q₁₀ [J]. Global Change Biology, 2001, 7(2): 223-230.

[23] Yu G R, Wen X F, Li Q K, et al. Seasonal patterns and environmental control of ecosystem respiration in subtropical and temperate forest in China [J]. Science in China Series D: Earth Sciences, 2004, 34(SⅡ): 84-94.

[24] Churkina G, Running S W. Contrasting climatic controls on the estimated productivity of global terrestrial biomes [J]. Ecosystems, 1998, 1(2): 206-215.

[25] Wen X F, Wang H M, Wang J L, et al. Ecosystem carbon exchanges of a subtropical evergreen coniferous plantation subjected to seasonal drought, 2003-2007 [J]. Biogeosciences, 2010, 7(1): 357-369.

[26] Rambal S, Ourcival J M, Joffre R, et al. Drought controls over conductance and assimilation of a Mediterranean evergreen ecosystem: Scaling from leaf to canopy [J]. Global Change Biology, 2003, 9(12): 1813-1824.

[27] Reichstein M, Tenhunen J D, Roupsard O, et al. Ecosystem respiration in two Mediterranean evergreen Holm Oak forests: Drought effects and decomposition dynamics [J]. Functional Ecology, 2002, 16(1): 27-39.

[28] ZHENG Ze-mei, YU Gui-rui, WEN Xue-fa, et al. Temperature and biotic factor control the seasonal and interannual variations of ecosystem respiration: A case study of winter wheat-summer maize double agroecosystem [J]. 资源科学, 2009, 31(4): 656-662.[郑泽梅, 于贵瑞, 温学发, 等. 温度和生物因子对农田生态系统呼吸的影响——以华北平原冬小麦-夏玉米复种农田生态系统为例. Resources Science, 2009, 31(4): 656-662.]

[29] Suyker A E, Verma S B, Burba G G, et al. Gross primary production and ecosystem respiration of irrigated maize and irrigated soybean during a growing season [J]. Agricultural and Forest Meteorology, 2005, 131(3/4): 180-190.

[30] Kato T, Tang Y, Gu S, et al. Temperature and biomass influences on interannual changes in CO₂ exchange in an alpine meadow on the Qinghai‐Tibetan Plateau [J]. Global Change Biology, 2006, 12(7): 1285-1298.

[31] Xu M, Qi Y. Spatial and seasonal variations of Q₁₀ determined by soil respiration measurements at a Sierra Nevadan forest [J]. Global Biogeochemical Cycles, 2001, 15(3): 687-696.

[32] 刘允芬, 李家永, 陈永瑞, 等. 红壤丘陵区森林植被恢复的增湿效应初探[J]. 自然资源学报, 2001, 16(5): 457-461.[LIU Yun-fen, LI Jia-yong, CHEN Yong-rui, et al. The effects of forest rehabilitation on microclimate in red earth hilly area of China. Journal of Natural Resources, 2001, 16(5): 457-461.]

[33] 孙晓敏, 温学发, 于贵瑞, 等. 中亚热带季节性干旱对千烟洲人工林生态系统碳吸收的影响[J]. 中国科学D辑: 地球科学, 2006(S1): 103-110.[SUN Xiao-min, WEN Xue-fa, YU Gui-rui, et al. The impact of seasonal drought in on carbon uptake in a subtropical coniferous plantation. Science in China Series D: Earth Sciences, 2006(S1): 103-110.]

[34] Zhang W J, Wang H M, Wen X F, et al. Freezing-induced loss of carbon uptake in a subtropical coniferous plantation in southern China [J]. Annals of Forest Science, 2011, 68(6): 1151-1161.

[35] Wofsy S C, Goulden M L, Munger J W, et al. Net exchange of CO₂ in a mid-latitude forest [J] Science, 1993, 260(5112): 1314.

[36] Aubinet M, Grelle A, Ibrom A, et al. Estimates of the annual net carbon and water exchange of forests: The EUROFLUX methodology [J]. Advances in Ecological Research, 2000, 30: 113-175.

[37] Foken T, Wichura B. Tools for quality assessment of surface-based flux measurements [J]. Agricultural and Forest Meteorology, 1996, 78(1/2): 83-105.

[38] Wilczak J M, Oncley S P, Stage S A. Sonic anemometer tilt correction algorithms [J]. Boundary-Layer Meteorology, 2001, 99(1): 127-150.

[39] Webb E K, Pearman G I, Leuning R. Correciton of flux measurements for density effects due to heat and water-vapor transfer [J]. Quarterly Journal of the Royal Meteorological Society, 1980, 106(447): 85-100.

[40] Sun X, Wen X, Yu G, et al. Seasonal drought effects on carbon sequestration of a mid-subtropical planted forest of southeastern China [J]. Science in China Series D: Earth Sciences, 2006, 49: 110-118.

[41] Griffis T J, Black T A, Morgenstern K, et al. Ecophysiological controls on the carbon balances of three southern boreal forests [J]. Agricultural and Forest Meteorology, 2003, 117(1/2): 53-71.

[42] Fang C, Moncrieff J B. The dependence of soil CO₂ efflux on temperature [J]. Soil Biology and Biochemistry, 2001, 33(2): 155-165.

[43] Law B E, Falge E, Gu L, et al. Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation [J]. Agricultural and Forest Meteorology, 2002, 113(1/4): 97-120.

[44] Luo Y, Wan S, Hui D, et al. Acclimatization of soil respiration to warming in a tall grass prairie [J]. Nature, 2001, 413(6856): 622-625.

[45] Yu G R, Zhang L M, Sun X M, et al. Environmental controls over carbon exchange of three forest ecosystems in eastern China [J]. Global Change Biology, 2008, 14(11): 2555-2571.

[46] Davidson E A, Verchot L V, Cattanio J H, et al. Effects of soil water content on soil respiration in forests and cattle pastures of eastern Amazonia [J]. Biogeochemistry, 2000, 48(1): 53-69.

[47] Cox P M, Betts R A, Jones C D, et al. Acceleration of global warming due to carbon-cycle feedbacks in a coupled climate model [J]. Nature, 2000, 408(6809): 184-187.

[48] Valentini R, Matteucci G, Dolman A J, et al. Respiration as the main determinant of carbon balance in European forests [J]. Nature, 2000, 404(6780): 861-865.

[49] Griffis T J, Black T A, Gaumont-Guay D, et al. Seasonal variation and partitioning of ecosystem respiration in a southern boreal aspen forest [J]. Agricultural and Forest Meteorology, 2004, 125(3/4): 207-223.