青藏高原草地生态系统碳循环研究进展

摘要/Abstract

摘要： 青藏高原属于气候变化的敏感区和生态脆弱带,对气候变化和人类活动扰动十分敏感,在未来全球碳循环调控中发挥着重要的作用。为增进对青藏高原高寒草地生态系统碳循环的理解,综述了近10年来气候变化、氮沉降和人类活动干扰下青藏高原温室气体排放、土壤碳库变化以及模型模拟应用等方面的最新研究进展。概括出高寒草地生态系统碳循环研究的草地类型主要包括高寒草原、高寒草甸、灌丛草甸草原、沼泽化草甸以及高寒湿地等。阐述了温室气体产生的机理、青藏高原高寒草地碳循环的源汇关系,指出温度升高、放牧、氮沉降是影响青藏高原温室气体排放、土壤碳库变化最重要的外界扰动,但是温室气体排放、土壤碳库对这3个因子之间协同作用的响应目前还不清楚。现有的高寒草地生态系统碳循环模型,主要以植被类型为基础,大多只考虑了水热因子,很少包含土壤因子和生物因子及其协同作用的影响。在此基础上,指出未来拟加强的研究重点: 1)冻融交替过程土壤温室气体排放研究; 2)非生长季土壤呼吸作用研究; 3)碳循环和植物物候耦合研究; 4)高寒草地生态系统碳循环模型的开发。

Abstract: The Qinghai-Tibetan Plateau is susceptible to climate change and anthropogenic perturbation, due to its fragile ecosystems which play a vital role in mediating future global carbon cycling. To enhance our understanding of the carbon cycling of alpine grassland on the Qinghai-Tibetan Plateau, green-house gases emissions, changes of soil carbon pools, and modeling applications were reviewed in the context of global change, nitrogen deposition and human disturbances, based on research over the last decade. Generally, most attention has been focused on alpine steppe, alpine meadow, shrubland meadow steppe, swamp meadow and alpine wetland. Additionally, The mechanism of greenhouse gas emissions and the shift between source and sink of alpine grassland are summarised. Rising temperatures, grazing activity and nitrogen deposition all exerted significant impacts on greenhouse gas emissions and carbon cycling. However, the responses of carbon cycling to simultaneous changes of these factors is still unknown. On the basis of vegetation type, most recent carbon cycling models failed to incorporate the modulation between biotic and abiotic factors and their relationships. Finally, it was noted that the following four areas required special attention in future studies: 1) greenhouse gas emissions in the course of freeze and thaw cycles; 2) soil respiration observation during non-growing seasons; 3) coupled study on carbon cycling with plant phenology; and 4) the development of some suitable carbon cycling models for alpine grassland.

中图分类号:

S812.29

秦彧,宜树华,李乃杰,任世龙,王晓云,陈建军. 青藏高原草地生态系统碳循环研究进展[J]. 草业学报, 2012, 21(6): 275-285.

QIN Yu, YI Shu-hua, LI Nai-jie, REN Shi-long, WANG Xiao-yun, CHEN Jian-jun. Advance in studies of carbon cycling on alpine grasslands of the Qinghai-Tibetan Plateau[J]. Acta Prataculturae Sinica, 2012, 21(6): 275-285.

参考文献

[1] Houghon J H, Ding Y, Griggs D J, et al. Climate Change 2001: The Scientific Basis[M]. Cambridge: Cambridge University Press, 2001: 944.
[2] Schimel D, Melillo J M, Tian H Q, et al. Contribution of increasing CO₂ and climate to carbon storage by ecosystems in the United States[J]. Science, 2000, 287: 2004-2006.
[3] Melillo J M, Field C B, Moldan B. Interactions of the Major Biogeochemical Cycles: Global Change and Human Impacts[M]. Washington, D C, USA: Island Press, 2003: 320.
[4] 陈宝玉, 刘世荣, 葛剑平, 等. 川西亚高山针叶林土壤呼吸速率与不同土层温度的关系[J]. 应用生态学报, 2007, 18(6): 1219-1224.
[5] Raich J W, Tufekcioglu A. Vegetation and soil respiration: correlations and controls[J]. Biogeochemistry, 2000, 48: 71-90.
[6] Kane E S, Valentine D W, Schuur E A G, et al. Soil carbon stabilization along climate and stand productivity gradients in black spruce forests of interior Alaska[J]. Canadian Journal of Forest Research, 2005, 35: 2118-2129.
[7] Carter M S, Ambus P, Albert K R, et al. Effects of elevated atmospheric CO₂, prolonged summer drought and temperature increase on N₂O and CH₄ fluxes in a temperate heathland[J]. Soil Biology & Biochemistry, 2011, 43(8): 1-11.
[8] 王玲玲, 孙志高, 牟晓杰, 等. 黄河口滨岸潮滩湿地CO₂、N₂O和CH₄通量特征初步研究[J]. 草业学报, 2011, 20(3): 51-61.
[9] 陈先江, 王彦荣, 侯扶江. 草地生态系统温室气体排放机理及影响因素[J]. 草业科学, 2011, 28(5): 722-728.
[10] 武高林, 杜国祯. 青藏高原退化高寒草地生态系统恢复和可持续发展探讨[J]. 自然杂志, 2007, 29(3): 159-164.
[11] Han J G, Zhang Y J, Wang C J, et al. Rangeland degradation and restoration management in China[J]. The Rangeland Journal, 2008, 30: 233-239.
[12] IPCC (Intergovernmental Panel on Climate Change). Climate Change 2007: the Physical Science Basis: Summary for Policy Makers[M]. Cambridge, UK: Cambridge University Press, 2007.
[13] 于海英, 许建初. 气候变化对青藏高原植被影响研究综述[J]. 生态学杂志, 2009, 28(4): 747-754.
[14] 岳广阳, 赵林, 赵拥华, 等. 青藏高原草地生态系统碳通量研究进展[J]. 冰川冻土, 2010, 32(1): 166-174.
[15] 秦大河, 丁一汇, 王绍武, 等. 中国西部生态环境变化与对策建议[J]. 地球科学进展, 2002, 17: 314-319.
[16] Bond-Lamberty B, Thomson A. A global database of soil respiration data[J]. Biogeosciences, 2010, 7: 1915-1926.
[17] 肖胜生, 董云社, 齐玉春, 等. 草地生态系统土壤有机碳库对人为干扰和全球变化的响应研究进展[J]. 地球科学进展, 2009, 24(10): 1138-1148.
[18] Pei Z Y, Ouyang H, Zhou C P, et al. Carbon balance in an alpine steppe in the Qinghai-Tibet Plateau[J]. Journal of Integrative Plant Biology, 2009, 51(5): 521-526.
[19] 许鹏. 草地资源调查规划学[M]. 北京: 中国农业出版社, 2000.
[20] 李凌浩, 陈佐忠. 草地生态系统碳循环及其对全球变化的响应I. 碳循环的分室模型、碳输入与贮量[J]. 植物学通报, 1998, 15(2): 14-22.
[21] 鲍芳, 周广胜. 中国草原土壤呼吸作用研究进展[J]. 植物生态学报, 2010, 34(6): 713-726.
[22] Li X D, Fu H, Guo D, et al. Partitioning soil respiration and assessing the carbon balance in a Setaria italica (L.) Beauv. cropland on the Loess Plateau, Northern China[J]. Soil Biology & Biochemistry, 2010, 42: 337-346.
[23] 王建林, 欧阳华, 王忠红, 等. 青藏高原高寒草原生态系统植被碳密度分布规律及其与气候因子的关系[J]. 植物资源与环境学报, 2010, 19(1): 1-7.
[24] Yang Y H, Fang J Y, Ji C J, et al. Soil inorganic carbon stock in the Tibetan alpine grasslands[J]. Global Biogeochemical Cycles, 2010, 24, doi: 10. 1029/2010GB003804.
[25] Wang S P, Yang X X, Lin X W, et al. Methane emission by plant communities in an alpine meadow on the Qinghai-Tibetan Plateau: a new experimental study of alpine meadows and oat pasture[J]. Biology Letters, 2009, 5: 535-538.
[26] Li N, Wang G X, Yang Y, et al. Plant production, and carbon and nitrogen source pools, are strongly intensified by experimental warming in alpine ecosystems in the Qinghai-Tibet Plateau[J]. Soil Biology Biochemistry, 2011, 43: 942-953.
[27] Zhao L, Li Y N, Xu S X, et al. Diurnal, seasonal and annual variation in net ecosystem CO₂ exchange of an alpine shrub land on Qinghai-Tibetan Plateau[J]. Global Change Biology, 2006, 12: 1940-1953.
[28] Cao G M, Xu X L, Long R J, et al. M ethane emissions by alpine plant communities in the Qinghai-Tibet Plateau[J]. Biology Letters, 2008, 4(6): 681-684.
[29] Wang J F, Wang G X, Hu H C, et al. The influence of degradation of the swamp and alpine meadows on CH₄ and CO₂ fluxes on the Qinghai-Tibetan Plateau[J]. Environmental Earth Sciences, 2010, 60: 537-548.
[30] Wu G L, Liu Z H, Zhang L, et al. Long-term fencing improved soil properties and soil organic carbon storage in an alpine swamp meadow of western China[J]. Plant and Soil, 2010, 332: 331-337.
[31] Chen H, Wu N, Yao S P, et al. Diurnal variation of methane emissions from an alpine wetland on the eastern edge of Qinghai-Tibetan Plateau[J]. Environmental Monitoring and Assessment, 2010, 164: 11-28.
[32] Schlesinger W H, Jeffrey A A. Soil respiration and the global carbon cycle[J]. Biogeochemistry, 2000, 48: 7-20.
[33] Shi P L, Sun X M, Xu L L, et al. Net ecosystem CO₂ exchange and controlling factors in a steppe-Kobresia meadow on the Tibetan Plateau[J]. Science in China(Ser. D, Earth Sciences), 2006, 49 (Supp. II): 207-218.
[34] Kato T, Tang Y H, Gu S, et al. Carbon dioxide exchange between the atmosphere and an alpine meadow ecosystem on the Qinghai-Tibetan Plateau, China[J]. Agricultural and Forest Meteorology, 2004, 124: 121-134.
[35] 任继周, 梁天刚, 林慧龙, 等. 草地对全球气候变化的响应及其碳汇潜势研究[J]. 草业学报, 2011, 20(2): 1-22.
[36] Kutzbach L, Wille C, Pfeiffer E M, et al. The exchange of carbon dioxide between wet arctic tundra and the atmosphere at the Lena River Delta, Northern Siberia[J]. Biogeosciences, 2007, 4: 869-890.
[37] Marchesini L B, Papale D, Reichstein M, et al. Carbon balance assessment of a natural steppe of southern Siberia by multiple constraint approach[J]. Biogeosciences, 2007, 4: 581-595.
[38] Gu S, Tang Y H, Du M Y, et al. Short-term variation of CO₂ flux in relation to environment al controls in an alpine meadow on the Qinghai-Tibetan Plateau[J]. Journal of Geophysical Research, 2003, 108: 4670-4679.
[39] 王杰, 叶柏生, 张世强, 等. 青藏高原东北部高寒草甸CO₂通量变化特征[J]. 冰川冻土, 2011, 33(3): 646-653.
[40] Bahn M, Knapp M, Garajova Z, et al. Root respiration in temperate mountain grasslands differing in land use[J]. Global Change Biology, 2006, 12: 995-1006.
[41] Karhu K, Fritze H, Kaihamalainen, et al. Temperature sensitivity of soil carbon fractions in boreal forest soil[J]. Ecology, 2010, 91(2): 370-376.
[42] 张金霞, 曹广民, 周党卫, 等. 高寒矮嵩草草甸大气-土壤-植被-动物系统碳素储量及碳素循环[J]. 生态学报, 2003, 23(4): 627-634.
[43] Bradford M A, Davies H A, Frey S D, et al. Thermal adaptation of soil microbial respiration to elevated temperature[J]. Ecology Letters, 2008, 11: 1316-1327.
[44] Lin X W, Zhang Z H, Wang S P, et al. Response of ecosystem respiration to warming and grazing during the growing seasons in the alpine meadow on the Tibetan plateau[J]. Agricultural and Forest Meteorology, 2011, 151: 792-802.
[45] Cao G M, Tang Y H, Mo W H, et al. Grazing intensity alters soil respiration in an alpine meadow on the Tibetan plateau[J]. Soil Biology & Biochemistry, 2004, 36: 237-243.
[46] Xu X L, Liu W, Kiely G. Modeling the change in soil organic carbon of grassland in response to climate change: Effects of measured versus modelled carbon pools for initializing the Rothamsted Carbon model[J]. Agriculture, Ecosystems and Environment, 2011, 140: 372-381.
[47] Jassal R S, Black T A, Roy R, et al. Effect of nitrogen fertilization on soil CH₄ and N₂O fluxes, and soil and bole respiration[J]. Geoderma, 2011, 162: 182-186.
[48] 李仁洪, 涂利华, 胡庭兴, 等. 模拟氮沉降对华西雨屏区慈竹林土壤呼吸的影响[J]. 应用生态学报, 2010, 21(7): 1649-1655.
[49] Jiang C M, Yu G R, Fang H J, et al. Short-term effect of increasing nitrogen deposition on CO₂, CH₄ and N₂O fluxes in an alpine meadow on the Qinghai-Tibetan Plateau, China[J]. Atmospheric Environment, 2010, 44: 2920-2926.
[50] Bowden R, Davidson E, Savage K, et al. Chronic nitrogen additions reduce total soil respiration and microbial respiration in temperate forest soils at the Harvard Forest[J]. Forest Ecology and Management, 2004, 196: 43-56.
[51] Zak D R, Holmes W E, Burton A J, et al. Simulated atmospheric NO₃^- deposition increases soil organic matter by slowing decomposition[J]. Ecological Applications, 2008, 18: 2016-2027.
[52] 詹力扬, 陈立奇. 海洋N₂O的研究进展[J]. 地球科学进展, 2006, 21(3): 269-277.
[53] Fluckiger J, Dallenbach A, Blunier T, et al. Variations in atmospheric N₂O concentration during abrupt climate changes[J]. Science, 1999, 285: 227-230.
[54] Liu L L, Greaver T L. A review of nitrogen enrichment effects on three biogenic GHGs: the CO₂ sink may be largely offset by stimulated N₂O and CH₄ emission[J]. Ecology Letters, 2009, 12: 1103-1117.
[55] Prieme S C. Natural perturbations, drying-wetting and freezing-thawing cycles and the emission of nitrous oxide, carbon dioxide and methane from farmed organic soils[J]. Soil Biology and Biochemistry, 2001, 33: 2083-2091.
[56] Edwards A C, Cresser M S. Freezing and its effect on chemical and biological properties of soil[J]. Advances in Soil Science, 1992, 18: 59-79.
[57] Sharma S, Szele Z, Schilling R, et al. Influence of freeze-thaw stress on the structure and function of microbial communities and denitrifying populations in soil[J]. Applied and Environmental Microbiology, 2006, 72(3): 2148-2154.
[58] Groffman P G, Hardy J P, Driscoll C T, et al. Snow depth, soil freezing, and fluxes of carbon dioxide, nitrous oxide and methane in a northern hardwood forest[J]. Global Change Biology, 2006, 13: 1748-1760.
[59] Petersen S O, Mutegi J K, Hansen E M, et al. Tillage effects on N₂O emissions as influenced by a winter cover crop[J]. Soil Biology & Biochemistry, 2011, 43: 1509-1517.
[60] Stehfest E, Bouwman L. N₂O and NO emission from agricultural fields and soils under natural vegetation: summarizing available measurement data and modeling of global annual emissions[J]. Nutrient Cycling in Agroecosystems, 2006, 74: 207-228.
[61] 杜岩功, 曹广民, 邓永翠, 等. 金露梅灌丛草甸氧化亚氮排放特征及冻融交替的影响研究[J]. 山地学报, 2009, 27(6): 688-697.
[62] Pei Z Y, Ouyang H, Zhou C P, et al. N₂O exchange within a soil and atmosphere profile in alpine grasslands on the Qinghai-Xizang[J]. Plateau Acta Botanica Sinica, 2004, 46 (1): 20-28.
[63] 王德宣. 若尔盖高原泥炭沼泽二氧化碳、甲烷和氧化亚氮排放通量研究[J]. 湿地科学, 2010, 8(3): 220-224.
[64] 万运帆, 李玉娥, 高清竹, 等. 夏季放牧强度对藏北草原温室气体排放的影响[J]. 草业科学, 2010, 27(11): 1-6.
[65] Hu Y G, Chang X F, Lin X W, et al. Effects of warming and grazing on N₂O fluxes in an alpine meadow ecosystem on the Tibetan plateau[J]. Soil Biology & Biochemistry, 2010, 42: 944-952.
[66] Houghton J T, Ding Y, Griggs D J, et al. Climate Change 2001: The Scientific Basis[M], Cambridge: Cambridge University Press, 2001, 239-287.
[67] Forster P, Ramaswamy V, Artaxo P, et al. Methane soil-vegetation-atmosphere fluxes in tropical ecosystems[J]. Interciencia, 2007, 32(1): 30-34.
[68] Keppler F, Hamilton J T, Brass M, et al. Methane emissions from terrestrial plants under aerobic conditions[J]. Nature, 2006, 439: 187-191.
[69] Khalil M A K. Atmospheric Methane: Its Role in the Global Environment[M]. Berlin: Springer, 2000: 1-8.
[70] 冯虎元, 程国栋, 安黎哲. 微生物介导的土壤甲烷循环及全球变化研究[J]. 冰川冻土, 2004, 26(4): 411-419.
[71] 金会军, 程国栋, 徐柏青, 等. 青藏高原花石峡冻土站高寒湿地CH₄排放研究[J]. 冰川冻土, 1998, 20(2): 45-47.
[72] Allard V, Soussana J F, Falcimagne R, et al. The role of grazing management for the net biome productivity and greenhouse gas budget (CO₂, N₂O and CH₄) of semi-natural grassland[J]. Agriculture, Ecosystems and Environment, 2007, 121: 47-58.
[73] 杜睿, 陈冠雄. 不同放牧强度对草原生态系统N₂O和CH₄排放通量的影响[J]. 河南大学学报(自然科学版), 1997, 27(2): 79-85.
[74] Hirota M, Tang Y H, Hu Q W, et al. The potential importance of grazing to the fluxes of carbon dioxide and methane in an alpine wetland on the Qinghai-Tibetan Plateau[J]. Atmospheric Environment, 2005, 39: 5255-5259.
[75] 齐玉春, 董云社, 杨小红, 等. 放牧对温带典型草原含碳温室气体CO₂、CH₄通量特征的影响[J]. 资源科学, 2005, 27(2): 103-109.
[76] Conrad R. The global methane cycle: recent advances in understanding the microbial processes involveded[J]. Environmental Microbiology Reports, 2009, 1(5): 285-292.
[77] Keppler F, Hamilton J T G, Mc Roberts W C, et al. Methoxyl groups of plant pectin as a precursor of atmospheric methane: evidence from deuterium labelling studies[J]. New Phytologist, 2008, 178 (4): 808-814.
[78] Crutzen P J, Sanhueza E, Brenninkmeijer C A M. Methane production from mixed tropical savanna and forest vegetation in Venezuela[J]. Atmospheric Chemistry and Physics Discussions, 2006, 6: 3093-3097.
[79] Wang Z P, Han X G, Wang G G, et al. Aerobic methane emission from plants in the Inner Mongolia steppe[J]. Environmental Science and Technology, 2008, 42(1): 62-68.
[80] Lashof D A. The dynamic greenhouse: feedback processes that may influence future concentrations of atmospheric trace gases and climate change[J]. Nature Climate Change, 1989, 14: 213-242.
[81] 张金屯. 全球气候变化对自然土壤碳、氮循环的影响[J]. 地理科学, 1998, 18(5): 463-471.
[82] Luo Y Q, Zhou X H. 土壤呼吸与环境[M]. 姜丽芬, 曲来叶, 周玉梅, 等译. 北京: 高等教育出版社, 2006.
[83] 方精云, 刘国华, 徐嵩龄. 中国陆地生态系统的碳库[A]. 见: 王庚辰, 温玉璞. 温室气体浓度和排放检测及相关过程[C]. 北京: 中国环境科学出版社, 1996: 109-128.
[84] 王根绪, 程国栋, 沈永平. 青藏高原草地土壤有机碳库及其全球意义[J]. 冰川冻土, 2002, 24(6): 693-700.
[85] Davidson E A, Janssens I A. Temperature sensitivity of soil carbon decomposition and feedbacks to climate change[J]. Nature, 2006, 440: 165-173.
[86] Wan S Q, Xia J Y, Liu W X, et al. Photosynthetic overcompensation under nocturnal warming enhances grassland carbon sequestration[J]. Ecology, 2009, 90(10): 2700-2710.
[87] 周晓宇, 张称意, 郭广芬. 气候变化对森林土壤有机碳贮藏影响的研究进展[J]. 应用生态学报, 2010, 21(7): 1867-1874.
[88] Anderson J M. Soil and climate change[J]. Advances in Ecological Research, 1992, 22: 188-210.
[89] Welker J M, Fahnestock J T, Henry G H R, et al. CO₂ exchange in three Canadian High Arctic ecosystems: response to long-term experimental warming[J]. Global Change Biology, 2004, 10: 1981-1995.
[90] Day T D, Ruhland C T, Xiong F S. Warming increases aboveground plant biomass and C stocks in vascular-plant-dominated Antarctic tundra[J]. Global Change Biology, 2008, 14: 1827-1843.
[91] Sardans J, Peuelas J, Estiarte M, et al. Warming and drought alter C and N concentration, allocation and accumulation in a Mediterranean shrubland[J]. Global Change Biology, 2008, 14: 2304-2316.
[92] Wan Y F, Erda L, Xiong W, et al. Modeling the impact of climate change on soil organic carbon stock in upland soils in the 21st century in China[J]. Agriculture, Ecosystems and Environment, 2011, 141: 23-31.
[93] Niu S L, Sherry R A, Zhou X H, et al. Nitrogen regulation of the climate-carbon feedback: evidence from a long-term global change experiment[J]. Ecology, 2010, 91(11): 3261-3273.
[94] Yang Y H, Fang J Y, Tang Y H, et al. Storage, patterns and controls of soil organic carbon in the Tibetan grasslands[J]. Global Change Biology, 2008, 14: 1592-1599.
[95] 陶贞, 沈承德, 高全洲, 等. 高寒草甸土壤有机碳储量及其垂直分布特征[J]. 地理学报, 2006, 21(7): 720-728.
[96] Liu X D, Chen B D. Climatic warming in the Tibetan Plateau during recent decades[J]. International Journal of Climatology, 2000, 20(14): 1729-1742.
[97] Thompson L G, Yao T, Mosley-Thompson E, et al. A high-resolution millennial record of the South Asian Monsoon from Himalayan ice cores[J]. Science, 2000, 289: 1916-1919.
[98] 李东, 黄耀, 吴琴, 等. 青藏高原高寒草甸生态系统土壤有机碳动态模拟研究[J]. 草业学报, 2010, 19: 160-168.
[99] Luo C Y, Xu G P, Chao Z G, et al. Effect of warming and grazing on litter mass loss and temperature sensitivity of litter and dung mass loss on the Tibetan plateau[J]. Global Change Biology, 2010, 16(5): 1606-1617.
[100] 董云社, 齐玉春, 耿元波. 草地生态系统过程研究[A]. 见: 陈泮勤. 地球系统碳循环[C]. 北京: 科学出版社, 2004: 249.
[101] Mapfumo E, Naeth M A, Baron V S, et al. Grazing impacts on litter and roots: perennial versus annual grasses[J]. Journal of Range Management, 2002, 55: 16-22.
[102] Schumana G E, Janzenb H H, Herrick J E. Soil carbon dynamics and potential carbon sequestration by rangelands[J]. Environmental Pollution, 2002, 116: 391-396.
[103] Fernandeza D P, Neff J C, Reynolds R L. Biogeochemical and ecological impacts of livestock grazing in semi-arid southeastern Utah, USA[J]. Journal of Arid Environments, 2008, 72: 777-791.
[104] Luo C Y, Xu G P, Wang Y F, et al. Effects of grazing and experimental warming on DOC concentrations in the soil solution on the Qinghai-Tibet Plateau[J]. Soil Biology & Biochemistry, 2009, 41: 2493-2500.
[105] Wang G X, Qian J, Cheng G D, et al. Soil organic carbon pool of grassland soils on the Qinghai-Tibetan Plateau and its global implication[J]. The Science of the Total Environment, 2002, 291: 207-217.
[106] Wang Y F, Fu B J, Lü Y H, et al. Effects of vegetation restoration on soil organic carbon sequestration at multiple scales in semi-arid Loess Plateau, China[J]. Catena, 2011, 85: 58-66.
[107] Zhou Z Y, Li F R, Chen S K, et al. Dynamics of vegetation and soil carbon and nitrogen accumulation over 26 years under controlled grazing in a desert shrubland[J]. Plant and Soil, 2011, 1341: 257-268.
[108] Piao S L, Fang J Y, He J S. Variations in vegetation net primary production in the Qinghai-Xizang Plateau, China, from 1982 to 1999[J]. Climatic Change, 2006, 74: 253-267.
[109] 裴志永, 周才平, 欧阳华, 等. 青藏高原高寒草原区域碳估测[J]. 地理研究, 2010, 29(11): 102-110.
[110] Li Z Q, Yu G R, Xiao X M, et al. Modeling gross primary production of alpine ecosystems in the Tibetan Plateau using MODIS images and climate data[J]. Remote Sensing of Environment, 2007, 107: 510-519.
[111] Fu G, Shen Z X, Zhang X Z, et al. Modeling gross primary productivity of alpine meadow in the northern Tibet Plateau by using MODIS images and climate data[J]. Acta Ecologica Sinica, 2010, 30: 264-269.
[112] Zhang Y Q, Tang Y H, Jiang J, et al. Characterizing the dynamics of soil organic carbon in grasslands on the Qinghai-Tibetan Plateau[J]. Science in China Series D: Earth Sciences, 2007, 50: 113-120.
[113] Tan K, Ciais P, Piao S L, et al. Application of the ORCHIDEE global vegetation model to evaluate biomass and soil carbon stocks of Qinghai-Tibetan grasslands[J]. Global Biogeochemical Cycles, 2010, 24: 1-12.
[114] Ni J. A simulation of biomes on the tibetan plateau and their responses to global climate change[J]. Mountain Research and Development, 2000, 20(1): 80-89.
[115] Zhuang Q, He J, Lu Y, et al. Carbon dynamics of terrestrial ecosystems on the Tibetan Plateau during the 20th century: an analysis with a process-based biogeochemical model[J]. Global Ecology And Biogeography, 2010, 19: 649-662.
[116] Luo T X, Li W H, Zhu H Z. Estimated biomass and productivity of natural vegetation on the Tibet Plateau[J]. Ecological Applications, 2002, 12: 980-997.
[117] 周才平, 欧阳华, 曹宇, 等. “一江两河”中部流域植被净初级生产力估算[J]. 应用生态学报, 2008, 19: 1071-1076.
[118] 张永强, 唐艳鸿, 姜杰. 青藏高原草地生态系统土壤有机碳动态特征[J]. 中国科学D辑地球科学, 2006, 36(12): 1140-1147.
[119] Wang Y H, Zhou G S, Wang Y H. Modeling responses of the meadow steppe dominated by Leymus chinensis to climate change[J]. Climatic Change, 2007, 82: 437-452.
[120] Zhou G S, Jia B R, Han G X, et al. Toward a general evaluation model for soil respiration (GEMSR)[J]. Science in China Series C: Life Sciences, 2008, 51: 254-262.
[121] 毛留喜, 孙艳玲, 延晓冬. 陆地生态系统碳循环模型研究概述[J]. 应用生态学报, 2006, 17(11): 2189-2195.
[122] Bardgett R D, Freeman C, Ostle N J. Microbial contributions to climate change through carbon cycle feedbacks[J]. The ISME Journal, 2008, 2: 805-814.
[123] Cruz-Martínez K, Suttle K B, Brodie E L, et al. Despite strong seasonal responses, soil microbial consortia are more resilient to long-term changes in rainfall than overlying grassland[J]. The ISME Journal, 2009, 3: 738-744.
[124] 高清竹, 万运帆, 李玉娥, 等. 基于CASA模型的藏北地区草地植被净第一性生产力及其时空格局[J]. 应用生态学报, 2007, 18 (11): 2526-2532.
[125] 王景升, 张宪洲, 赵玉萍, 等. 羌塘高原高寒草地生态系统生产力动态[J]. 应用生态学报, 2010, 21: 1400-1404.
[126] 李树德, 程国栋. 青藏高原冻土图[Z]. 兰州: 甘肃文化出版社, 1996.
[127] Christensen T R, Johansson T, Kerman H J, et al. Thawing sub-arctic permafrost: Effects on vegetation and methane emissions[J]. Geophysical Research Letters, 2004, 31: L04501.
[128] 张凡, 祁彪, 温飞, 等. 不同利用程度高寒干旱草地碳储量的变化特征分析[J]. 草业学报, 2011, 20(4): 11-18.
[129] Mikan C J, Schimel J P, Doyle A P. Temperature controls of microbial respiration in arctic tundra soils above and below freezing[J]. Soil Biology & Biochemistry, 2002, 34: 1785-1795.
[130] Feng X J, Nielsen L L, Simpson M J. Responses of soil organic matter and microorganisms to freeze-thaw cycles[J]. Soil Biology & Biochemistry, 2007, 39: 2027-2037.
[131] Hubbard R M, Ryan M G, Elder K, et al. Seasonal patterns in soil surface CO₂ flux under snow cover in 50 and 300 year old subalpine forests[J]. Biogeochemistry, 2005, 73: 93-107.
[132] Monson R K, Sparks J P, Rosenstiel T N, et al. Climatic influences on net ecosystem CO₂ exchange during the transition from wintertime carbon source to springtime carbon sink in a high-elevation, subalpine forest[J]. Oecologia, 2005, 146: 130-147.
[133] 杨红露, 秦纪洪, 孙辉. 冻融交替对土壤CO₂及N₂O释放效应的研究进展[J]. 土壤, 2010, 42(4): 526-525.
[134] 葛全胜, 戴君虎, 郑景云. 物候学研究进展及中国现代物候学面临的挑战[J]. 中国科学院, 2010, 25(3): 310-316.
[135] Yu H Y, Luedeling E, Xu J C. Winter and spring warming result in delayed spring phenology on the Tibetan Plateau[J]. PNAS, 2010, 107(51): 22151-22156.
[136] Chen H, Zhu Q, Wu N, et al. Delayed spring phenology on the Tibet Plateau may also be attributable to other factors than winter and spring warming[J]. PNAS, 2011, 108(19): 93.
[137] Shen M G. Spring phenology was not consistently related to winter warming on the Tibet Plateau[J]. PNAS, 2011, 108(19): 91-92.
[138] Yi S H, Zhou Z Y. Increasing contamination might have delayed spring phenology on the Tibet Plateau[J]. PNAS, 2011, 108(19): 94.
[139] Yuste J C, Janssens I A, Carrara A, et al. Annual Q₁₀ of soil respiration reflects plant phonological patterns as well as temperature sensitivity[J]. Global Change Biology, 2004, 10: 161-169.
[140] Piao S L, Ciais P L, Friedlingstein P, et al. Net carbon dioxide losses of northern ecosystems in response to autumn warming[J]. Nature, 2008, 451: 49-52.