气候变化背景下中国自然湿地生态系统甲烷排放的时空变化
发布时间：2019-05-14 23:16
【摘要】：甲烷是一种重要的温室气体,其增温潜势为二氧化碳(CO2)的28倍,自工业时代以来贡献了大约20%的地球增温。源汇的动态变化决定了大气甲烷的丰度。当前大气甲烷浓度几乎为工业时代前的三倍,但是过去三十年间这种上升趋势并没有持续。上世纪90年代开始大气甲烷浓度增长速率几乎降低到零,2006年后又恢复了增长。由于近期大气甲烷增长速率异常的年际变化以及多个甲烷排放源存在的不确定性,增强我们对于全球甲烷排放源的了解具有重要的意义。全球变暖背景下,考虑到湿地生态系统甲烷排放对于大气甲烷循环极为重要的贡献,全球尺度未来湿地甲烷排放与气候变化之间的反馈研究已经初步展开,然而目前我们关于未来气候变化背景下中国尺度自然湿地甲烷排放的时空变化的认知还处于空白阶段。TRIPLEX-GHG模型是新一代用于量化陆地生态系统温室气体动态的过程模型,在全球植被动力学模型—Integrated Biosphere Simulator(IBIS)的基础上发展而来。经过IBIS模型与新的甲烷生物地理化学模块和水位模块耦合,TRIPLEX-GHG模型可用于模拟自然湿地甲烷排放的动态,其在估算全球自然湿地甲烷排放量级和采集时间序列上甲烷排放动态方面表现优异,可以作为可靠的过程模型用于模拟不同类型自然湿地在不同条件下甲烷排放的时空格局。本研究应用TRIPLEX-GHG模型,以三种代表性浓度路径(Representative Concentration Pathways,RCPs)情景下,第五阶段耦合模式比较计划(Coupled Model Intercomparison Project Phase 5,CMIP5)中的四种全球气候模式的未来气候变化数据结果,以及RCPs对应的未来CO2变化数据作为模型的输入数据,在保持中国现有自然湿地分布不变情况下,模拟未来气候变化背景下,2006—2100年中国自然湿地生态系统甲烷排放的时空变化。TRIPLEX-GHG模型的模拟结果表明:保持中国现有自然湿地分布不变,在RCP2.6、RCP4.5和RCP8.5情景下,21世纪末,中国自然湿地甲烷排放量与当前水平相比分别增长32.0%、55.3%和90.8%。中国大陆南方自然湿地甲烷排放高于中部和北方,且自西向东呈现上升趋势。甲烷高通量排放区域主要集中在长江中下游湿地、东北湿地和珠江沿岸湿地。RCP4.5和RCP8.5情景下全国大部分自然湿地甲烷排放通量增加,而RCP2.6情景下本世纪中后期甲烷排放上升趋势得到控制并开始下降,到世纪末部分地区(尤其是青藏高原地区)甲烷排放通量与当前水平相比有所降低。本研究可以为我国温室气体排放清单的制定提供参考依据,同时也对科学地管理湿地起到了一定的辅助作用。
[Abstract]:Methane is an important greenhouse gas with a warming potential of 28 times that of carbon dioxide (CO2), which has contributed about 20 per cent of the Earth's warming since the industrial age. The dynamic change of source and sink determines the abundance of methane in the atmosphere. Atmospheric methane concentrations are almost three times higher than they were before the industrial age, but this upward trend has not continued over the past three decades. The growth rate of atmospheric methane concentration dropped to almost zero in the 1990 s and resumed after 2006. Due to the recent interannual variation of atmospheric methane growth rate anomalies and the uncertainty of multiple methane emission sources, it is of great significance to enhance our understanding of global methane emission sources. In the context of global warming, considering the extremely important contribution of methane emissions from wetland ecosystems to the atmospheric methane cycle, the feedback research on the relationship between methane emissions from wetlands and climate change on a global scale has been initially carried out. However, our cognition about the temporal and spatial variation of methane emissions from natural wetlands in China under the background of climate change in the future is still in a blank stage. TRIPLEX-GHG model is a new generation of process model used to quantify the dynamics of greenhouse gases in terrestrial ecosystems. It is developed on the basis of Integrated Biosphere Simulator (IBIS), a global vegetation dynamics model. After coupling IBIS model with new methane biogeography module and water level module, TRIPLEX-GHG model can be used to simulate the dynamics of methane emission from natural wetlands. It can be used as a reliable process model to simulate the temporal and spatial pattern of methane emission from different types of natural wetlands under different conditions. In this study, the TRIPLEX-GHG model was used to compare the future climate change data results of the four global climate models in the fifth stage coupling model (Coupled Model Intercomparison Project Phase 5, CMIP 5) under the scenario of three representative concentration paths (Representative Concentration Pathways,RCPs). And the future CO2 change data corresponding to RCPs are used as the input data of the model, and the future climate change background is simulated under the condition that the distribution of natural wetlands in China remains unchanged. The temporal and spatial variation of methane emissions from natural wetland ecosystems in China from 2006 to 2100. The simulation results of TRIPLEX-GHG model show that the distribution of natural wetlands in China remains unchanged. Under RCP2.6,RCP4.5 and RCP8.5 scenarios, at the end of the 21st century, Compared with the current level, methane emissions from natural wetlands in China increased by 32.0%, 55.3% and 90.8%, respectively. Methane emissions from natural wetlands in the south of China were higher than those in the middle and north, and increased from west to east. High throughput methane emission areas are mainly concentrated in wetlands in the middle and lower reaches of the Yangtze River, northeast wetlands and wetlands along the Pearl River. Under RCP 4.5 and RCP8.5 scenarios, methane emission fluxes from most natural wetlands in China have increased. However, under the RCP2.6 scenario, the upward trend of methane emissions in the middle and late part of this century is controlled and began to decline, and by the end of the century, the methane emission fluxes in some areas (especially in the Qinghai-Xizang Plateau) are lower than the current levels. This study can provide a reference for the formulation of greenhouse gas emission inventory in China, and also play a certain auxiliary role in the scientific management of wetlands.
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P467;X171
本文编号：2477124
[Abstract]:Methane is an important greenhouse gas with a warming potential of 28 times that of carbon dioxide (CO2), which has contributed about 20 per cent of the Earth's warming since the industrial age. The dynamic change of source and sink determines the abundance of methane in the atmosphere. Atmospheric methane concentrations are almost three times higher than they were before the industrial age, but this upward trend has not continued over the past three decades. The growth rate of atmospheric methane concentration dropped to almost zero in the 1990 s and resumed after 2006. Due to the recent interannual variation of atmospheric methane growth rate anomalies and the uncertainty of multiple methane emission sources, it is of great significance to enhance our understanding of global methane emission sources. In the context of global warming, considering the extremely important contribution of methane emissions from wetland ecosystems to the atmospheric methane cycle, the feedback research on the relationship between methane emissions from wetlands and climate change on a global scale has been initially carried out. However, our cognition about the temporal and spatial variation of methane emissions from natural wetlands in China under the background of climate change in the future is still in a blank stage. TRIPLEX-GHG model is a new generation of process model used to quantify the dynamics of greenhouse gases in terrestrial ecosystems. It is developed on the basis of Integrated Biosphere Simulator (IBIS), a global vegetation dynamics model. After coupling IBIS model with new methane biogeography module and water level module, TRIPLEX-GHG model can be used to simulate the dynamics of methane emission from natural wetlands. It can be used as a reliable process model to simulate the temporal and spatial pattern of methane emission from different types of natural wetlands under different conditions. In this study, the TRIPLEX-GHG model was used to compare the future climate change data results of the four global climate models in the fifth stage coupling model (Coupled Model Intercomparison Project Phase 5, CMIP 5) under the scenario of three representative concentration paths (Representative Concentration Pathways,RCPs). And the future CO2 change data corresponding to RCPs are used as the input data of the model, and the future climate change background is simulated under the condition that the distribution of natural wetlands in China remains unchanged. The temporal and spatial variation of methane emissions from natural wetland ecosystems in China from 2006 to 2100. The simulation results of TRIPLEX-GHG model show that the distribution of natural wetlands in China remains unchanged. Under RCP2.6,RCP4.5 and RCP8.5 scenarios, at the end of the 21st century, Compared with the current level, methane emissions from natural wetlands in China increased by 32.0%, 55.3% and 90.8%, respectively. Methane emissions from natural wetlands in the south of China were higher than those in the middle and north, and increased from west to east. High throughput methane emission areas are mainly concentrated in wetlands in the middle and lower reaches of the Yangtze River, northeast wetlands and wetlands along the Pearl River. Under RCP 4.5 and RCP8.5 scenarios, methane emission fluxes from most natural wetlands in China have increased. However, under the RCP2.6 scenario, the upward trend of methane emissions in the middle and late part of this century is controlled and began to decline, and by the end of the century, the methane emission fluxes in some areas (especially in the Qinghai-Xizang Plateau) are lower than the current levels. This study can provide a reference for the formulation of greenhouse gas emission inventory in China, and also play a certain auxiliary role in the scientific management of wetlands.
【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P467;X171
【参考文献】
相关期刊论文 前1条
1 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年04期
，本文编号：2477124
本文链接：https://www.wllwen.com/kejilunwen/huanjinggongchenglunwen/2477124.html
