气候变化对中亚草地生态系统碳循环的影响研究

doi:10.12118/j.issn.1000-6060.2018.06.23

摘要/Abstract

摘要： 准确评估草地生产力、碳源/碳汇功能，分析气候变化对草地生态系统碳循环的影响，对于草地资源的合理开发和有效保护至关重要。选取对气候变化以及人类干扰高度敏感的中亚干旱区草地生态系统为研究对象，利用Biome-BGC模型，模拟分析其NPP、NEP的年际变化趋势及其空间分布格局。结果显示：（1）1979-2011年中亚地区草地生态系统NPP年平均值为135.6 gC·m^-2·a^-1，且随着时间的推移呈现出波动下降的趋势，下降速率为0.34 gC·m^-2·a^-1。（2）NEP的年平均值为-8.3 gC·m^-2·a^-1，表现为碳源，且该值随着时间的推移呈现出波动上升的趋势，上升速率为0.58 gC·m^-2·a^-1。（3）NPP高值区域在降水较为丰富的天山山脉附近以及哈萨克斯坦北部。（4）NPP的年际变化与降水量的年际变化趋势基本一致，相关系数为0.52；NPP与温度的相关系数为-0.28，未达到显著相关水平。本研究实现了Biome-BGC模型在中亚干旱区草地生态系统的应用，对评价干旱区草地生态系统碳源/碳汇功能及其在全球碳循环和全球变化中的作用、实现中亚草地生态系统的可持续利用、完善区域和全球碳循环理论体系具有重要意义。

关键词: 气候变化, 草地生态系统, Biome-BGC模型, 碳循环

Abstract: The global ecosystem has experienced tremendous climate change since the 20th Century.The arid and semi-arid region of Central Asia (referred to as "Central Asia") is one of the most sensitive regions to climate variations.With the intensification of human disturbances such as grazing,the grassland ecosystem in Central Asia has become one of the most uncertain regions in global carbon cycle estimation.Therefore,to accurately evaluate grassland ecosystem productivity,carbon source/carbon sink function and analyze the impact of climate change and human disturbance on the grassland carbon cycle is crucial for grassland resource's reasonable development and effective protection.Ecosystem process-based models are widely used by the researchers to simulate the climate change effects on grassland ecosystem structure and function.The Biome-BGC model,proposed by the Numerical Terradynamic Stimulation Group (NTSG) of Montana University in the United States has been widely used to simulate the spatio-temperal patterns of carbon dynamics in arid areas with limited field data.In this study,we adopted the biogeochemical cycle model Biome-BGC to simulate carbon dynamics in Central Asia for grassland ecosystem.The results indicated as follows:(1) the averaged NPP value of grassland in Central Asia is 135.6 gC·m^-2·a^-1,which decreased at a rate of 0.34 gC·m^-2·a^-1. (2) the averaged NPP value of grassland in Central Asia is -8.3 gC·m^-2·a^-1,acted as a carbon source,which increased at a rate of 0.58 gC·m^-2·a^-1. (3) NPP high values are mainly presented nearby the Tianshan Mountains and Northern Kazakhstan with relatively abundant rainfall. (4) The interannual variation of NPP is basically consistent with the variation trend of precipitation,the correlation coefficient is 0.52,and the correlation coefficient of NPP and temperature is -0.28,which does not reach significant correlation level.The Biome-BGC model has achieved good simulation results in this area,but uncertainty still exist.The uncertainties mainly come from the following aspects:(1) Biome-BGC is based on the ideal assumption that the vegetation composition remains unchanged,which is not consistent with the reality. (2) It is difficult to accurately parameterize the model because of the lack of reliable field data. (3) The low resolution of the meteorological data.This study proves the usability of Biome-BGC model in grassland ecosystem in arid grasslands of Central Asia.It is of great significance to evaluate the carbon source/sink potential and achieve the sustainable utilization of grassland ecosystem in Central Asia.

Key words: climate change, grassland ecosystems, Biome-BGC, carbon cycle

中图分类号:

S812.29

韩其飞, 陆研, 李超凡. 气候变化对中亚草地生态系统碳循环的影响研究[J]. 干旱区地理, 2018, 41(6): 1351-1357.

HAN Qi-fei, LU Yan, LI Chao-fan. Impact of climate change on grassland carbon cycling in Central Asia[J]. 干旱区地理, 2018, 41(6): 1351-1357.

参考文献

[1] 韩其飞.气候变化背景下放牧对中亚草地生态系统碳动态的影响[D].北京:中国科学院大学,2014.[HAN Qifei.Impact of grazing on carbon dynamics of grassland ecosystems in Central Asia under climate change[D].Beijing:University of Chinese Academy of Sciences,2014.]
[2] 於琍,朴世龙. IPCC第五次评估报告对碳循环及其他生物地球化学循环的最新认识[J].气候变化研究进展,2014,10(1):33-36.[YU li,PIAO Shilong.Key scientific points on carbon and other biogeochemical cycles from the IPCC fifth assessment report[J].Climate Change Research,2014,10(1):33-36.]
[3] SCHIMEL D,MELILLO J,TIAN H,et al.Contribution of increasing CO₂ and climate to carbon storage by ecosystems in the United States[J].Science,2000,287(5460):2004-6.
[4] 王瑞利.基于多模型的森林-草原交错带碳动态模拟研究[D].呼和浩特:内蒙古农业大学,2017.[WANG Ruili.Simulation of carbon dynamics in forest-steppe ecotone based on multiple models[D].Hohhot:Inner Mongolia Agricultural University,2017.]
[5] 王超.应用BIOME-BGC模型研究典型生态系统的潜热通量——半干旱地区吉林通榆的模拟[D].南京:南京农业大学,2006.[WANG Chao.With BIOME-BGC model on the latent heat fluxes of the typical ecosystem:Simulations in semi-arid area at Tongyu,Jilin Province[D].南京:Nanjing Agricultural University,2006.]
[6] SOLOMON S.IPCC:Climate change the physical science basis[C]//AGU Fall Meeting.San Francisco:AGU Fall Meeting Abstracts,2007:123-124.
[7] FEDERICI S,BOER R,GONZALEA S,et al.2013 Revised supplementary methods and good practice guidance arising from the kyoto protocol[M].IPCC,2014.
[8] RIEDO M,GYALISTRAS D,GRUB A,et al.Modelling grassland responses to climate change and elevated CO₂[J].Acta Oecologica,1997,18(3):305-311.
[9] LI T, GRANT R F, FLANAGAN L B.Climate impact on net ecosystem productivity of a semi-arid natural grassland:Modeling and measurement[J].Agricultural & Forest Meteorology,2004,126(1):99-116.
[10] XU X,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 & Environment,2011,140(3-4):372-381.
[11] LIN Huilong,FENG Qisheng,LIANG Tiangang,et al.Modelling global-scale potential grassland changes in spatio-temporal patterns to global climate change[J].International Journal of Sustainable Development & World Ecology,2013,20(1):83-96.
[12] 李凌浩,刘先华.内蒙古锡林河流域羊草草原生态系统碳素循环研究[J]. 植物学报,1998,40(10):955-961.[LI Linghao,LIU Xianhua.Study on the carbon cycle of Leymus chinese steppe in the Xilin River Basin[J].Acta Botanica Sinica,1998,40(10):955-961.]
[13] LUO G, HAN Q,ZHOU D,et al.Moderate grazing can promote aboveground primary production of grassland under water stress[J].Ecological Complexity,2012,11(3):126-136.
[14] 周伟,何顺兵,杨晗,等.基于BIOME-BGC模型的三峡库区不同草地群落碳源/汇的动态变化研究[J].山地学报,2018,36(1):13-22.[ZHOU Wei,HE Shunbing,YANG Han,et al.Dynamic changes of carbon source and sink in different grassland communities in three gorges reservoir area based on BIOME-BGC model[J].Mountain Research,2018,36(1):13-22.]
[15] 王昆.中亚干旱地区植被退化遥感监测与分析[D].青岛:山东科技大学,2013.[WANG Kun.Remote sensing monitoring and analysis of vegetation degradation in arid regions of Central Asia[D].Qingdao:Shandong University of Science and Technology,2013.]
[16] 殷刚,孟现勇,王浩,等.1982-2012年中亚地区植被时空变化特征及其与气候变化的相关分析[J].生态学报,2017,37(9):3149-3163.[YIN Gang,MENG Xianyong,WANG Hao,et al.Spatial-temporal variation of vegetation and its correlation with climate change in Central Asia during the period of 1982-2012[J].Acta Ecological Sinica,2017,37(9):3149-3163.]
[17] 孙燕瓷,马友鑫,曹坤芳,等.基于Biome-BGC模型的西双版纳橡胶林碳收支模拟[J].生态学报,2017,37(17):5732-5741.[SUN Yanci,MA Youxin,CAO Kunfang,et al.Simulation of carbon budget in rubber plantations in Xishuangbanna based on the Biome-BGC model[J].Acta Ecological Sinica,2017,37(17):5732-5741.]
[18] 韩其飞,罗格平,李超凡,等.放牧对新疆草地生态系统碳源/汇的影响模拟研究[J].生态学报,2017,37(13):4392-4399.[HAN Qifei,LUO Geping,LI Chaofan,et al.Modeling the grazing effect of grassland on the carbon source/sink in Xinjiang[J].Acta Ecological Sinica,2017,37(13):4392-4399.]
[19] WHITE M A,THORNTON P E,RUNNING S W,et al.Parameterization and sensitivity analysis of the BIOME-BGC terrestrial ecosystem model:Net primary production controls[J].Earth Interactions,2000,4(3):1-84.
[20] YU G,FANG H,FU Y,et al. Research on carbon budget and carbon cycle of terrestrial ecosystems in regional scale:A review[J].Acta Ecologica Sinica,2011.
[21] BAI Y.Influence of seasonal distribution of precipitation on primary productivity of Stipa krylovii community[J].Acta Phytoecologica Sinica,1999,23(2).
[22] WANG Y,ZHOU G.Responses of temporal dynamics of abovegro-und net primary productivity of Leymus chinensis community to precipitation fluctuation in Inner Mongolia[J].Acta Ecologica Sinica,2004,24(6):1140-1145.
[23] DAVIDSON E A,JANSSENS I A.Temperature sensitivity of soil carbon decomposition and feedbacks to climate change[J].Nature,2006,440(7081):165-173.
[24] CURIEL Y J,JANSSENS I A,CARRARA A,et al.Interactive eff-ects of temperature and precipitation on soil respiration in a temperate maritime pine forest[J].Tree Physiology,2003,23(18):1263-1270.
[25] 赵文龙.中国北方草原物候、生产力和土壤碳储量对气候变化的响应[D].兰州:兰州大学,2012.[ZHAO Wenlong.Response of phenology,productivity and carbon stocksto climate change in northern Chinese steppes[D].Lanzhou:Lanzhou University,2012.]
[26] BELLAMY P R,LOVELAND P J,BRADLEY R I,et al.Carbon losses from all soils across England and Wales 1978-2003[J]. Nature,2005,437,245-248.
[27] SCHIPPER L A,BAISDEN W T,PARFITT R L,et al.Large losses of soil C and N from soil profiles under pasture in New Zealand during the past 20 years[J].Global Change Biology,2010,13(6):1138-1144.
[28] MYNENI R B,KEELING C D,TUCKER C J,et al.Increased plant growth in the northern high latitudes from 1981 to 1991[J].Nature,1997,386(6626):698-702.
[29] KIRSCHBAUM M U F.The temperature dependence of soil organic matter decomposition,and the effect of global warming on soil organic C storage[J].Soil Biology and Biochemistry,1995,27(6):753-760.
[30] 高春雨.气候变化情景下黑龙江省森林碳循环模拟[D].哈尔滨:东北林业大学,2015.[GAO Chunyu.Simulation of forest cycle carbon under the changes of climate scenario in Heilongjiang[D].Harbin:Northeast Forestry University,2015.]
[31] 李东.基于CENTURY模型的高寒草甸土壤有机碳动态模拟研究[D].南京:南京农业大学,2011.[LI Dong.Modelling dynamics of soil organic carbon in alpine meadow by using CENTURY model[D].Nanjing:Nanjing Agricultural University,2011.]