自然湿地甲烷排放模拟研究——模型的灵敏度分析与应用     

李婷婷  张稳 《气候与环境研究》2010,15(3):257-268

对甲烷湿地排放模型CH4MODwetland进行灵敏度分析表明,环境驱动因素——温度和地表水深是影响甲烷排放通量的主要因素,地表水深对季节性积水沼泽甲烷排放通量的灵敏度大于常年积水沼泽。模型对植物和土壤输入参数的灵敏度响应依次为Wmax(地上生物量最大值)FR(地下净初级生产力占植物总净初级生产力的比例)fV(植被类型系数)TAmax(植物从生长初期到最大地上生物量所需有效积温)ρ(容量),OM(土壤有积质含量)SAND(土壤砂粒含量)。以经验水位模型驱动CH4MODwetland,模拟三江平原毛果苔草和小叶章沼泽(1950年代～2000年代),以及若尔盖高原木里苔草和乌拉苔草沼泽(1960年代～2000年代)多年甲烷排放通量的变化。结果表明,年代际甲烷排放通量的变化主要受降水量的影响,但气候变暖使得降水量基本相同的年代甲烷排放通量增加:三江平原毛果苔草沼泽和小叶章沼泽(1980年代～2000年代比1950年代～1970年代模拟的甲烷排放通量分别增加了9.5%和8.3%;若尔盖高原乌拉苔草沼泽和木里苔草沼泽(1990年代～2000年代比1960年代～1970年代)分别增加了6.0%和5.5%。该结论能够为评估未来气候变化对中国湿地甲烷排放的影响提供依据。  相似文献   

以科学发展观为指导，积极应对气候变化   总被引：1，自引：1，他引：0  

韦力行 《气象研究与应用》2008,29(2):1-4

气候变化已经对全球生态、环境、经济和社会可持续发展以及外交和国家安全产生极大影响,引起各国政府、公众和学术界的极大关注。气候变化关系人类的生存和发展,应对气候变化实现可持续发展具有重要性和紧迫性。我们要以科学发展观为指导,把握好共同但有区别的责任,积极应对气候变化。  相似文献   

Produced fluids and shallow groundwater in coalbed methane (CBM) producing regions of Alberta, Canada: Trace element and rare earth element geochemistry     

Katrina Cheung  Hamed Sanei  Patrick Klassen  Bernhard Mayer  Fariborz Goodarzi 《International Journal of Coal Geology》2009,77(3-4):338-349

  相似文献   

Structural controls on fractured coal reservoirs in the southern Appalachian Black Warrior foreland basin   总被引：1，自引：0，他引：1  

Richard H. Groshong Jr.  Jack C. Pashin  Marcella R. McIntyre 《Journal of Structural Geology》2009,31(9):874

Coal is a nearly impermeable rock type for which the production of fluids requires the presence of open fractures. Basin-wide controls on the fractured coal reservoirs of the Black Warrior foreland basin are demonstrated by the variability of maximum production rates from coalbed methane wells. Reservoir behavior depends on distance from the thrust front. Far from the thrust front, normal faults are barriers to fluid migration and compartmentalize the reservoirs. Close to the thrust front, rates are enhanced along some normal faults, and a new trend is developed. The two trends have the geometry of conjugate strike-slip faults with the same σ₁ direction as the Appalachian fold-thrust belt and are inferred to be the result of late pure-shear deformation of the foreland. Face cleat causes significant permeability anisotropy in some shallow coal seams but does not produce a map-scale production trend.  相似文献   

The Classification and Model of Coalbed Methane Reservoirs   总被引：8，自引：0，他引：8  

SU Xianbo  LIN Xiaoying  SONG Yan  ZHAO Mengjun Henan University of the Sciences  Jiaozuo  Henan Research Institute of Petroleum Exploration  Development  PetroChin  Beijing 《《地质学报》英文版》2004,78(3):662-666

Coalbed methane has been explored in many basins worldwide for 30 years, and has been developed commercially in some of the basins. Many researchers have described the characteristics of coalbed methane geology and technology systematically. According to these investigations, a coalbed methane reservoir can be defined: "a coal seam that contains some coalbed methane and is isolated from other fluid units is called a coalbed methane reservoir". On the basis of anatomization, analysis, and comparison of the typical coalbed methane reservoirs, coalbed methane reservoirs can be divided into two classes: the hydrodynamic sealing coalbed methane reservoirs and the self-sealing coalbed methane reservoirs. The former can be further divided into two sub-classes: the hydrodynamic capping coalbed methane reservoirs, which can be divided into five types and the hydrodynamic driving coalbed methane reservoirs, which can be divided into three types. The latter can be divided into three types. Currently, hydrodynamic s  相似文献   

注入CO2提高煤层气产能的可行性研究   总被引：15，自引：0，他引：15  

吴建光  叶建平  唐书恒 《高校地质学报》2004,10(3):463-467

根据煤储层吸附一解吸机理,首次采用“解吸一注气一解吸”的实验方法,分别进行CH4,CO2的吸附一解吸和CO2注入置换煤层CH4实验,模拟了煤层气井“排采一注气一排采”的增产途径和效果。结果表明：在CH4和CO2二元体系的竞争吸附中,CO2组分的吸附速率是先快后慢,而CH4组分的吸附速率先慢后快,解吸时则相反,反映出CO2在竞争吸附中占据优势;注入CO2气体的数量越大和相对浓度越高,单位压降CH4解吸率和CO2吸附率就越高。实验结论对工业规模的煤层气开发试验具有指导意义。  相似文献   

Prediction Model of Coal Reservoir Pressure and its Implication for the Law of Coal Reservoir Depressurization     

YAN Xinlu  ZHANG Songhang  TANG Shuheng  LI Zhongcheng  WANG Kaifeng  YI Yongxiang  DANG Feng  HU Qiuping 《《地质学报》英文版》2019,93(3):692-703

The main methods of coalbed methane(CBM) development are drainage and depressurization, and a precise prediction of coal reservoir pressure is thus crucial for the evaluation of reservoir potentials and the formulation of reasonable development plans. This work established a new reservoir pressure prediction model based on the material balance equation(MBE) of coal reservoir, which considers the self-regulating effects of coal reservoirs and the dynamic change of equivalent drainage area(EDA). According to the proposed model, the reservoir pressure can be predicted based on reservoir condition data and the actual production data of a single well. Compared with traditional reservoir pressure prediction models which regard EDA as a fixed value, the proposed model can better predict the average pressure of reservoirs. Moreover, orthogonal experiments were designed to evaluate the sensitivity of reservoir parameters on the reservoir pressure prediction results of this proposed model. The results show that the saturation of irreducible water is the most sensitive parameter, followed by Langmuir volume and reservoir porosity, and Langmuir pressure is the least sensitive parameter. In addition, the pressure drop of reservoirs is negatively correlated with the saturation of irreducible water and the Langmuir volume, while it is positively correlated with porosity. This work analyzed the reservoir pressure drop characteristics of the CBM wells in the Shizhuangnan Block of the Qinshui Basin, and the results show that the CBM reservoir depressurization can be divided into three types, i.e., rapidly drop type, medium-term stability type, and slowly drop type. The drainage features of wells were reasonably interpreted based on the comprehensive analysis of the reservoir depressurization type; the latter was coupled to the corresponding permeability dynamic change characteristics, eventually proving the applicability of the proposed model.  相似文献   

天然气水合物赋存区甲烷渗漏活动的地球化学响应特征     

程俊  王淑红  黄怡  颜文 《海洋科学》2019,43(5):110-122

综述了天然气水合物赋存区甲烷渗漏活动的地球化学响应指标的研究进展,分析了应用单一指标识别甲烷渗漏活动各自所存在的问题,包括浅表层沉积物孔隙水中CH_4、SO_4~(2–)、Cl~–等离子浓度随深度的变化;浅层沉积物全岩W_(TOC)(W表示质量分数,TOC表示总有机碳)和W_(TS)(TS表示总硫)之间的相关性及比值;自生碳酸盐岩δ~(13)C和δ~(18)O;自生矿物重晶石、黄铁矿、自生石膏的δ~(34)S;有孔虫壳体和生物标志化合物的δ~(13)C等。结果表明孔隙水中的CH_4、SO4_~(2–)浓度及溶解无机碳的碳同位素组成可以用来识别目前正在发生的甲烷渗漏活动;而沉积物中的WTS、自生矿物的δ~(34)S、钡含量及其异常峰值和生物标志化合物的δ~(13)C等指标的联合使用可以更真实准确地反映地质历史时期天然气水合物赋存区的甲烷渗漏活动。因此,在实际研究过程中,可将孔隙水和沉积物两种介质的多种指标相结合。随着非传统稳定同位素(Fe、Ca、Mg等)和沉积物氧化还原敏感元素(Mo、V、U等)等研究的发展,甲烷渗漏活动地球化学响应指标的研究也将得到拓展,而多种地球化学指标的联合使用将为天然气水合物勘探及其形成分解过程识别研究提供重要的科学依据。  相似文献   

冷泉系统甲烷气体渗漏的声学特征及潜在环境效应     

尉建功  吴婷婷  邓希光  于宗泽  王力峰 《海洋学报(英文版)》2020,42(5):133-144

The amount of methane leaked from deep sea cold seeps is enormous and potentially affects the global warming,ocean acidification and global carbon cycle. It is of great significance to study the methane bubble movement and dissolution process in the water column and its output to the atmosphere. Methane bubbles produce strong acoustic impedance in water bodies, and bubble strings released from deep sea cold seeps are called "gas flares"which expressed as flame-like strong backscatter in the water column. We characterized the morphology and movement of methane bubbles released into the water using multibeam water column data at two cold seeps. The result shows that methane at site I reached 920 m water depth without passing through the top of the gas hydrate stability zone(GHSZ, 850 m), while methane bubbles at site II passed through the top of the GHSZ(597 m) and entered the non-GHSZ(above 550 m). By applying two methods on the multibeam data, the bubble rising velocity in the water column at sites I and II were estimated to be 9.6 cm/s and 24 cm/s, respectively. Bubble velocity is positively associated with water depth which is inferred to be resulted from decrease of bubble size during methane ascending in the water. Combined with numerical simulation, we concluded that formation of gas hydrate shells plays an important role in helping methane bubbles entering the upper water bodies, while other factors, including water depth, bubble velocity, initial kinetic energy and bubble size, also influence the bubble residence time in the water and the possibility of methane entering the atmosphere. We estimate that methane gas flux at these two sites is 0.4×10~6–87.6×10~6 mol/a which is extremely small compared to the total amount of methane in the ocean body, however, methane leakage might exert significant impact on the ocean acidification considering the widespread distributed cold seeps. In addition, although methane entering the atmosphere is not observed, further research is still needed to understand its potential impact on increasing methane concentration in the surface seawater and gas-water interface methane exchange rate, which consequently increase the greenhouse effect.  相似文献   

平端深海偏顶蛤(Gigantidas platifrons)实验室蓄养过程鳃部含菌上皮细胞超微结构动态变化研究     

钟兆山  王敏晓  孙园园  王孝程  陈浩  孙妍  李梦娜  李超伦 《海洋与湖沼》2020,51(4):952-959

平端深海偏顶蛤(Gigantidasplatifrons)是南海台西南冷泉区的典型优势物种,鳃丝上皮细胞内共生大量甲烷氧化菌,通过甲烷有氧氧化合成有机物为共生体系提供物质能量,是平端深海偏顶蛤赖以生存的重要能量来源器官,溶酶体在共生体系的营养互作和稳态维持中可能发挥重要作用,本研究使用电镜技术观测了常压培养过程中(0d,30d,90d)平端深海偏顶蛤共生体系中共生菌和溶酶体的动态变化,通过鳃上皮含菌细胞超显微结构的变化研究常压培养对深海共生体系的影响,并探讨溶酶体在宿主—共生菌营养传递和共生菌群稳态维持中的关键作用。研究发现,在原位状态样品中(0d)共生菌和溶酶体呈极化分布,细胞结构完整清晰;蓄养30d后,含菌细胞出现明显破碎,共生菌数量大幅降低,溶酶体数量、范围和消化程度大幅增加,对细胞顶端的甲烷氧化菌进行分解;而90d后,共生菌在溶酶体的作用下消失殆尽,鳃部有明显细胞脱落后留下的坑洞,细胞呈现空泡状,无法明确区分各种细胞组分。上述结果展示了长期常压蓄养过程中鳃上皮含菌细胞中溶酶体与甲烷氧化菌的动态变化,推测当共生菌丢失后溶酶体也同步降低活跃度,平端深海偏顶蛤在共生互作中通过溶酶体主导消化和调控共生菌。  相似文献