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151.
中国不同区域能源消费碳足迹的时空变化(英文)   总被引:2,自引:2,他引:2  
Study on regional carbon emission is one of the hot topics under the background of global climate change and low-carbon economic development, and also help to establish different low-carbon strategies for different regions. On the basis of energy consumption and land use data of different regions in China from 1999 to 2008, this paper established carbon emission and carbon footprint models based on total energy consumption, and calculated the amount of carbon emissions and carbon footprint in different regions of China from 1999 to 2008. The author also analyzed carbon emission density and per unit area carbon footprint for each region. Finally, advices for decreasing carbon footprint were put forward. The main conclusions are as follows: (1) Carbon emissions from total energy consumption increased 129% from 1999 to 2008 in China, but its spatial distribution pattern among different regions just slightly changed, the sorting of carbon emission amount was: Eastern China > Northern China > Central and Southern China > Southwest China > Northwest China. (2) The sorting of carbon emission density was: Eastern China > Northeast China > Central and Southern China > Northern China > Southwest China > Northwest China from 1999 to 2003, but from 2004 Central and Southern China began to have higher carbon emission density than Northeast China, the order of other regions did not change. (3) Carbon footprint increased significantly since the rapid increasing of carbon emissions and less increasing area of pro-ductive land in different regions of China from 1999 to 2008. Northern China had the largest carbon footprint, and Northwest China, Eastern China, Northern China, Central and Southern China followed in turn, while Southwest China presented the lowest area of carbon footprint and the highest percentage of carbon absorption. (4) Mainly influenced by regional land area, Northern China presented the highest per unit area carbon footprint and followed by Eastern China, and Northeast China; Central and Southern China, and Northwest China had a similar medium per unit area carbon footprint; Southwest China always had the lowest per unit area carbon footprint. (5) China faced great ecological pressure brought by carbon emission. Some measures should be taken both from reducing carbon emission and increasing carbon absorption.  相似文献   
152.
The prominent types of Danxia landform in Fangyan include enclosed valleys, mesas, peaks, stone columns and grooves etc. Their spatial combinations have regular configurations along the northwest–southeast direction: typical grooves and caves are located in the northwestern Wufengshuyuan mainly; abundant fresh collapsed stones may be observed in central Jimingfeng and Taohuafeng; stone drums and stone columns are in the southeastern Shiguliao particularly; enclosed valleys are encircling joints of peaks and plains from three directions east, west, and south. Their spatial combinations reflect that the developments of Danxia landform have undergone stages of geomorphic cyclical erosion in the form of weathering, collapse, transportation, sedimentation and other processes, together with the “sculpture” of external forces mainly as tectonic uplift. The picturesque Danxia landform began its formation at that point. Danxia landform developed mainly in the strata of Fangyan Formation (K1f) caused by the alluvial fan-braided river phase of anterior fan in the late period of the Early Cretaceous. Regular patterns of weathering of stones and features of braided alluvial phase sediments may be verified by the analysis of three groups of experimental data. Danxia landform of Fangyan is a unique representative of the “adolescent” development type in the application of the World Natural Heritages status in China, by virtue of its outstanding universal aesthetic and scientific value.  相似文献   
153.
简单概括了镁资源研究开发的状况,评述镁水泥研究的主要理论成果。指出以镁水泥为途径开发盐湖资源的重要性。同时表述了镁水泥研究领域的最新动态,指出当前镁水泥研究需要考虑的几个重大问题。  相似文献   
154.
We augment our scenario for the formation of astronomical objects from macroscopic superstrings by the assumption that the central matter keeps its identity in the fragmentation. From the condition that the angular momentum per mass squared of this matter should be less than the Kerr limit G/c, we obtain upper limits for the ratio of the mass of central black holes M(BH) to the mass M of the host object. This limit is M(BH)/M ≈ 0.001, and, expressed in observed quantities, approximately M(BH)/Mσ2/(v · c) where σ is the r.m.s. velocity, v the rotational velocity and c the velocity of light. The valuesM(BH) agree with the observed behaviour both in order of magnitude and in the variation with velocity dispersion. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
155.
地磁低点位移异常类型特征与地震活动   总被引:2,自引:0,他引:2  
黄雪香  余素荣 《地震》2000,20(4):39-44
通过对大量的地磁低点位移异常震例研究,结果表明: ① 地磁低点位移异常的形态、空间展布有明显的地区特征。异常大致可分为: 大范围异常和区域性异常二大类, 还可细分为 5个类型 ; ② 地磁低点位移异常与我国的地质活动构造有较密切的联系。 异常范围的大小、形态与异常所在地区的活动构造的规模、展布形态特征,以及这一地区即将发生的地震强度有关。  相似文献   
156.
157.
Trace and RE element geochemistry and genesis have been studied with respect to ferromanganese nodules from the sediments of the Pacific, Atlantic and Indian oceans.  相似文献   
158.
利用2003~2010年吉林省春季土壤含水率数据及相关数据,采用常规统计方法、地统计学方法和基于地理信息系统的空间分析方法,讨论吉林省春季土壤水分分布特征,并对其影响因素进行初步分析。结果表明,吉林省春季0~30 cm土壤平均含水率总体上呈由西向东逐渐增加的趋势,空间差异性显著,其中10 cm深度土壤含水率空间差异最大;土壤层之间的距离越近,土壤含水率的相关性越好,东部10 cm深度与其他层次土壤含水率的相关性好于中西部,中部相比东部和西部而言,各层次之间土壤含水率相关性最差。研究还发现,田间持水量和降水量是影响吉林省土壤含水率分布的主要因素,受土壤、气候等自然要素的空间异质性影响,田间持水量对中部和东部的土壤含水率影响更大,而降水对中部和西部的土壤含水率影响更大。  相似文献   
159.
杆洞铜矿床赋存于广西桂北最老地层─—中元古界四堡群中,矿体呈脉状产于杆洞花岗斑岩体及其外接触带围岩中,受NNE向断裂裂隙构造控制明显,矿石具细脉浸染状、块状构造,矿石平均品位Cu0.785—1.748%,矿石矿物主要为黄铜矿、斑铜矿、辉铜矿、黄铁矿,局部伴生方铅矿、闪锌矿,脉石矿物有石英、绢云母、绿泥石、黑云母,围岩蚀变主要为石英绢云母化与绿泥石化、黄铁矿化、硅化,据此认为属岩浆热液交代充填脉型矿床。  相似文献   
160.
A thick (200 m) rock salt mass covering Late Archean granitoids was exposed for the first time in the Early Proterozoic volcanogenic-sedimentary formations in the Onega trough of the east Baltic Shield by the Onega parametric well. The mineral composition of salts, their geochemical features, and the isotopic composition of carbonate carbon and oxygen have been studied. After fluid inclusions present in salts, their metamorphism temperature and isotopic composition of helium and argon were determined. The obtained results give evidence of the fact that rock salts and magnesites associated with them were formed in an evaporate basin with participation of deep crustal processes. The age of the underlying granitoids (2.716 ± 9 Ma) is determined using the Pb—Pb method.  相似文献   
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