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21.
We used the global atmospheric chemical transport model,GEOS-Chem,to simulate the spatial distribution and seasonal variation of surface-layer methane (CH4) in 2004,and quantify the impacts of individual domestic sources and foreign transport on CH4 concentrations over China.Simulated surface-layer CH4 concentrations over China exhibit maximum concentrations in summer and minimum concentrations in spring.The annual mean CH4 concentrations range from 1800 ppb over western China to 2300 ppb over the more populated eastern China.Foreign emissions were found to have large impacts on CH4 concentrations over China,contributing to about 85% of the CH4 concentrations over western China and about 80% of those over eastern China.The tagged simulation results showed that coal mining,livestock,and waste are the dominant domestic contributors to CH4 concentrations over China,accounting for 36%,18%,and 16%,respectively,of the annual and national mean increase in CH4 concentration from all domestic emissions.Emissions from rice cultivation were found to make the largest contributions to CH4 concentrations over China in the summer,which is the key factor that leads to the maximum seasonal mean CH4 concentrations in summer.  相似文献   
22.
塔里木盆地石油地质研究新进展和油气勘探主攻方向   总被引:30,自引:18,他引:30  
“十五”以来,塔里木盆地石油地质攻关研究取得了多项新进展,主要表现在: 1)发现库车前陆盆地既富气也富油; 2)克拉通区下古生界碳酸盐岩油气富集受储层控制,斜坡带富油; 3)哈得逊周缘东河砂岩具有形成大型地层油气藏的地质条件; 4)塔中地区志留系发育岩性油气藏; 5)下白垩统克孜勒苏群是塔西南喀什凹陷北缘的主要目的层; 6)塔东地区原油裂解气勘探潜力颇大。近期的勘探思路是:以温宿凸起及周缘为重点,加强预探;积极评价轮南奥陶系潜山、塔中多目的层和哈得逊周缘石炭系3个有利区;准备塔西南西部、塔北西部英买力和塔东及塔东南地区3个新领域。  相似文献   
23.
在水资源趋紧和水需求增长的背景下,水成为经济发展的约束资源,亟待“以水定城、以水定地、以水定人、以水定产”,把水资源作为最大的刚性约束,推动用水方式由粗放向节约集约转变。为将“以水四定”与农业、生活、工业、城镇发展相对应,本文将“地、人、产、城”分别定义为耕地面积、人口规模、工业增加值总量、城镇建设用地面积。在此基础上,初步探索了水资源承载评价方法,引入了“综合定额”的概念,力求揭示耕地与主要农作物、工业与耗水行业的内在联系与计算规则。通过全国31个省区市的评价结果显示,浪费情景处于超载,节约情景有较大盈余,倒逼节水行动。在水资源承载最大规模下,全国仍有超载区,耕地超载呈中部“塌陷”,人口超载呈环状“倒塌”,工业超载呈区域性“沦陷”,城镇用地超载呈沿海少点“亏空”,该区域需要从水资源总量、结构、效率等方面提升承载规模。  相似文献   
24.
聚氨酯泡沫塑料富集——ICP-MS测定化探样中微量金的方法   总被引:3,自引:0,他引:3  
试样经王水分解,在10%的王水溶液介质中,加一定量的铁盐,用聚氨酯泡沫塑料吸附富集金,1%硫脲溶液解脱,ICP-MS进行测定。实验结果表明,这种方法精密度高、准确度好,检出限低。其测定范围为0.028~500ng/g。  相似文献   
25.
Understanding where people depend the most on natural resources for their basic human needs is crucial for planning conservation and development interventions. For some people, nature is a direct source of food, clean water, and energy through subsistence uses. However, a high direct dependency on nature for basic needs makes people particularly sensitive to changes in climate, land cover, and land tenure. Based on more than 5 million household interviews conducted in 85 tropical countries, we identified where people highly depend on nature for their basic needs. Our results show that 1.2 billion people, or 30% of the population across tropical countries, are highly dependent on nature. In places where people highly depend on nature for their basic needs, nature-based strategies that protect, restore or sustainably manage ecosystems must be carefully designed to promote inclusive human development alongside environmental benefits.  相似文献   
26.
德国是近代自然地理学的发源地,也是人文地理学的故乡。近代德国地理学不仅助推了德国社会经济的发展,还为世界各国地理学的发展奠定了理论基础,推动了地理学的科学化、系统化与全球化。本文运用文献计量法综述国内外1975—2019年关于近代德国地理学的539篇文献,从年度载文量、研究者国别、研究方向和研究方法四方面入手,突出时间顺序与空间差异,系统梳理与凝练近代德国地理学家的理论与重要贡献,结果表明:近代德国自然地理学与人文地理学的经典理论,尤其是地质地貌、地学革命,以及区域、景观与环境三大学派、区位理论、地缘政治等领域对人类做出了卓越的贡献,近代德国地理学的理论与研究方法值得我们借鉴与思考。  相似文献   
27.
量化湖泊与邻近陆地的表面温度差异,拆分生物物理因子对其贡献是明确湖泊气候效应的基础。本文基于耦合CLM4.5的CESM模式模拟的1991—2010年全球气候数据,分析了全球湖泊表面温度效应(湖泊与邻近陆地的表面温度差异)的时空格局,利用IBPM因子拆分理论量化了生物物理因子对其贡献。结果表明:① 湖泊表面温度效应的季节变化明显,但年际变化不显著,北半球湖泊最强增温(4.37 K)和降温效应(-0.99 K)分别出现在9月和4月。② 除干旱区湖泊呈降温效应外,其他气候区的湖泊以增温效应为主,热带湖泊增温效应最强。③ 湖泊表面温度效应的生物物理主控因子随气候区改变,湖陆之间的蒸发差异是干旱区湖泊呈降温效应的主控因子,较低的对流散热效率是热带和温带湖泊呈增温效应的主控因子,反照率差异和冰雪融化潜热分别对寒带、极地湖泊表面温度效应的正贡献和负贡献最大。全球尺度上,湖陆之间的对流效率差异(3.77±0.13 K)和蒸发差异(-2.01±0.1 K)对湖泊表面温度效应的正、负贡献最大。  相似文献   
28.
正Dear Authors and Readers:First of all,on behalf of the new Editorial Board,I would like to express our sincere appreciation for your continuing support of our journal.This journal,founded in 1922,is the oldest geological journal in China.As the flagship journal of the  相似文献   
29.
The 2015 Paris Agreement was adopted in a geopolitical context that is very different from the post-Cold War era when the Climate Convention was negotiated. This new global climate deal responds to a more fragmented and multipolar world signified by the rise of major economies in the South. This paper examines the geopolitical landscape in which the Paris Agreement is enacted and implemented. We conduct a discursive analysis of the Nationally Determined Contributions submitted by parties to the Paris Agreement. We ask what policy discourses emerge in these national climate plans, which states cluster around them and how they compare to UNFCCC annex, geographical location, income group, and negotiation coalitions. Our findings suggest that liberal environmentalism retains a strong hold over the political imagination in the post-Paris landscape. However, we see points of diffraction and tensions that might give rise to conflict. While liberal environmentalism is only challenged in Nationally Determined Contributions from the global South, we conclude that conventional geopolitical patterns only partly explain the formation of discourse coalitions. In the Paris Agreement’s implementation stage discursive struggles are likely to become increasingly prominent. Discourse analysis facilitates understanding of disagreements on the Paris rulebook and the global stocktake.  相似文献   
30.
Cyclic climatic changes, as well as the press of anthropogenic impact, affect ecosystems of the river Argun basin. Specialization of basin management is industrial and agricultural. The main impact is connected with the development of mining companies (including the mining of ore and placer gold), energy facilities, and the formation of reservoirs in the basin of rivers: the Argun — the Hailar. As a result of natural and anthropogenic pressure, the limiting factor for ecosystem exploitation in this basin is water resources (water deficiency and its quality).  相似文献   
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