水稻不同生长期稻田能量收支、CO2通量模拟研究

利用国家自然科学基金重大项目“长江三角洲低层大气物理化学过程与生态系统的相互作用”野外观测资料，将1999年常熟稻田水稻四个不同生长期（插秧、拔节、抽穗和成熟）的太阳辐射、水汽压、气温和水平风速及降水作为简化生物圈（SiB2）模式的5个强迫变量，在合理设计模式参数的前提下，分别模拟了上述四个阶段的能量收支、CO₂通量。模拟结果表明:在水稻不同生长阶段的感热、潜热和下垫面热通量占净辐射的比例不同；CO₂通量的模拟结果与1996年国际稻田试验结果相似。该研究为利用自动气象站网的资料估计各站能量收支、CO₂通量、土壤水分平衡、以及土壤温度廓线提供了新证据。     

A geochemical and geophysical approach to derive a conceptual circulation model of CO2-rich mineral waters: A case study of Vilarelho da Raia, northern Portugal

The Vilarelho da Raia-Chaves region, located in northern Portugal adjacent to the Spanish border, is characterized by both hot and cold CO₂-rich mineral waters issuing from springs and drilled wells. The present paper updates the conceptual circulation model of the Vilarelho da Raia cold CO₂-rich mineral waters. Vilarelho da Raia mineral waters, dominated by Na and HCO₃ ions, have formed mainly by interaction with CO₂ of deep-seated mantle origin. The δ ¹⁸O, δ ²H and ³H values indicate that these waters are the result of meteoric waters infiltrating into Larouco Mountain, NW of Vilarelho da Raia, circulating at shallow depths in granitic rocks and moving into Vilarelho da Raia area. The conceptual geochemical and geophysical circulation model indicates that the hot and cold CO₂-rich mineral waters of Chaves (76 °C) and Vilarelho da Raia (17 °C) should be considered manifestations of similar but not the same geohydrological systems. Electronic Publication     

THE IMPACTS OF GLOBAL CHANGE ON DESERTIFICATION IN CHINA

ＩｎＣｈｉｎａ,ｄｅｓｅｒｔｓｍｏｖｉｎｇｎｏｒｔｈｗａｒｄｄｕｅｔｏｔｈｅｕｐｌｉｆｔｉｎｇｏｆｔｈｅＱｉｎｇｈａｉ-ＴｉｂｅｔＰｌａｔｅａｕａｒｅｄｉｓｔｒｉｂｕｔｅｄｉｎａｒｉｄ,ｓｅｍｉ-ａｒｉｄａｎｄｄｒｙｓｕｂ-ｈｕｍｉｄａｒｅａｓｏｆ35°-50°Ｎａｎｄ75°-125°Ｅ.Ｄｅｓｅｒｔｓ,ＧｏｂｉａｎｄｄｅｓｅｒｔｉｆｉｃａｔｉｏｎａｆｆｅｃｔｅｄａｒｅａｓｈｏｒｉｚｏｎｔａｌｌｙｃｒｏｓｓｅｄＮｏｒｔｈｗｅｓｔ,ＮｏｒｔｈａｎｄＮｏｒｔｈｅａｓｔＣｈｉｎａｉｎａｌｅｎｇｔｈｏｆ4,500ｋｍ.Ｔｈｅｖ…     

窑街三矿煤层高纯度二氧化碳运移和赋存模式

1.该矿高纯度CO₂的运移和赋存具有特殊的规律性。突出CO₂的通道是F₁₉断裂带及与之有联系的断层破碎带,还有煤系垫层J类磨拉石建造的砂砾岩孔隙和裂隙;2.该矿高纯度CO₂赋存的主要部位在煤层断裂带内及其周围的煤体下部,特别是下降盘的断裂带内。     

近百年来气候变化

根据当前气候变化研究中的新发现和新观点,综述了近百年来气候变化的属性成因和机制。阐述了气候是一个高度复杂的非线性系统,内部充满着错综复杂的耦合过程和反馈循环。重点介绍了CO_2含量在大气中的增加、火山喷发和海气异常等在近百年气候变化中所起的重要作用,并把气候变化与冷圈波动联系起来。     

陕西商州地区丹凤变质火山岩的地球化学特征

陕西商州地区丹凤变质火山岩具有洋内岛弧火山岩地球化学特征,它们是分别来自不同源区的拉斑玄武和钙碱性2个系列共存的一套变质火山岩。其Th/Ta比值高及Ni、Ta、Ti、Y和Yb含量低,表明岩石受到消减带组分的影响。种种证据表明,丹凤变质火山岩是早古生代华北地块南缘消减带之上洋内岛弧环境的产物。     

海洋表层流模式和月尺度海气耦合试验

本文第一部分设计了一个海洋表层流模式，较成功地模拟出冬夏季海表层中的大尺度洋流和海面高度第二部分是月时间尺度的海气耦合试验，将海表层洋流模式和球带范围的大气模式相耦合，用数值试验讨论了洋流和海气耦合方式对模拟结果的影响。     

A multi-methodological approach to determine CO2 and CH4 fluxes and concentrations in solid waste disposal

The municipal solid waste （MSW） landfills are the significant sources of atmospheric contamination, due to biogas production by anaerobic decomposition of organic matter via bacterial activity. Biogas released from landfills is commonly composed of a mixture of methane （55%-60%） and carbon dioxide （40%-45%）, with minor contents of N2, H2, CO and traces of toxic and bad smelling inorganic and organic compounds. Particular attention has to be paid to CH4 and CO2 because of their liability for the greenhouse effect. Presently, the U.S. methane emission from landfills is considered to be about 25% of the total methane released to the atmosphere. Accordingly, field measurements should be planned in order to verify and, eventually, optimize the amount of gases released from waste disposals to the atmosphere. Simultaneous measurements of methane and carbon dioxide fluxes are an effective tool to better evaluate： （1） the amount of biogas released, （2） the real efficiency of the impervious cover, and （3） the presence of anomalous degassing zones or of newly formed fractures. Static closed-chamber methods for CH4 and CO2 flux measurements have been developed and used in both natural and artificial systems. Furthermore, portable gas-chromatographers equipped with flame ionization detector （FID） and accumulation chamber connected to infrared detectors （IR） .have been utilized for measuring CH4 and CO2 fluxes, respectively. This paper deals with a detailed investigation that combines （1） CH4 and CO2 flux measurements from solid waste disposal and surrounding areas （determined by an accumulation chamber equipped with two IR detectors, respectively）, （2） chemical composition of soil and piezometer gases （collected in pre-evacuated glass tubes and analyzed by gas-chromatography）, and （3） CO2 linear concentration measurements on optical air paths with IR laser devices. This multi-methodological approach was successfully applied to an active MSW in Tuscany （Central Italy）. The analytical results have shown that the CO2/CH4 ratios of the piezometer gases have large variations, likely related to the different stage of decomposition processes affecting the heterogeneous solid material of the waste landfill. Significant contents of light hydrocarbons and BTX were also detected.     

俯冲洋岛玄武岩脱水释放的水流体成分：来自西天山榴辉岩相高压脉的约束

俯冲洋壳的脱水作用对于岛弧火山岩的成因具有重要意义。西天山高压低温变质带中切割主岩蓝片岩/榴辉岩的榴辉岩相脉体记录了古生代俯冲带中的脱水过程。脉体具有典型高压矿物组合：石榴石(＞8%)+绿辉石(15%)+石英(＞55%)+蓝闪石(5%)+冻蓝闪石(10%)±黝帘石±方解石。高压脉及其主岩的岩相学与矿物化学研究表明流体是在俯冲过程中蓝片岩向榴辉岩进变质条件下释放。脉的主量元素成分显示流体富Si。主岩的稀土元素和微量元素表明其原岩为洋岛玄武岩(OIB)。脉和主岩具有相似的微量元素配分模式,并且相对N-MORB都显示富Li、Be、Cs、Rb、Ba、Pb、La的特点。通过模拟计算,在高压脉、与脉平衡的流体以及模拟的原生流体中都富集流体活动性元素(Li、Be、Pb)和LILE(Cs、Rb、Ba),贫HFSE(Nb)和REE(Nd、Sm)。证实了在古生代南天山洋俯冲时洋岛玄武岩脱水释放出富Li、Be、LILE、La和Pb,贫HFSE和HREE的流体。     

济阳坳陷断裂活动和CO2气藏的关系研究

济阳坳陷在惠民凹陷和东营凹陷的地壳中各存在1个低速体,位于惠民凹陷上地壳底部的低速体是坳陷内已经发现火成岩的岩浆房以及CO₂的气体库。凹陷的边界断层在10~12km±的深度其倾角变得平缓,并以韧性剪切方式沿拆离带向下延伸。拆离带内岩石多为糜棱岩,在岩石圈上部巨大的压力作用下,呈现韧性状态的拆离带是良好的封盖层。由于拆离带的作用,沿岩石圈下部裂缝上升的岩浆和气体等在拆离带下部聚集而形成低速体。在地壳相对较稳定期,拆离带也处于较稳定阶段并起分隔作用;如果地壳发生拉分作用,则低速体也会随之发生暂时性破裂,从而导致低速体内的岩浆和气体运移、聚集和成藏。郯庐断裂是间接的成气断裂,埕南断裂及惠民凹陷内地幔隆起区上地幔及下地壳张性断裂是直接的成气断裂;高青—平南断层以及商店—平方王断层等为输气断裂;临邑—商河断层、林樊家断层和齐河—广饶断层等是有利的输气断裂。