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111.
112.
Environmental significance of snowpit chemistry in the typical monsoonal temperate glacier region,Baishui glacier no. 1, Mt Yulong,China 总被引:1,自引:0,他引:1
Li Zongxing He Yuanqing Pang Hongxi Wilfred H. Theakstone Zhang Ningning He Xianzhong Wang Shijing Pu Tao Du Jiankuo 《Environmental Geology》2009,58(6):1319-1328
Samples were collected from two snowpits in Baishui glacier no. 1, Mt Yulong, China, in May 2006. Snowpit chemistry was studied,
using ion tracer techniques, HYSPLIT model, factor analysis, correlation and trend analysis. It indicated that total cation
concentration is higher in 4,900-m snowpit than in 4,750-m snowpit, whereas total anion concentration is higher in 4,750-m
snowpit. Cations, especially Ca2+, dominate ionic concentrations in Baishui glacier no. 1. According to correlation analysis and factor analysis, ions can
be categorized as follows: Cl− and NO3
− as Group 1, SO4
2− as Group 2, Mg2+ and Ca2+ as Group 3, Na+ as Group 4, K+ as Group 5. Contribution made by terrestrial dust to ionic concentration accounts for 52.27, 100, 99.36, 98.91, 96.16 and
99.97% of Cl−, NO3
−, SO4
2−, K+, Mg2+ and Ca2+, respectively, in 4,900-m snowpit, and for 64.00, 100, 99.57, 98.63, 96.25 and 99.97% in 4,750-m snowpit. Local dust is the
principal source of snowpit chemical components. Pollutants brought from industrial areas of South Asia, Southeast Asia and
South China by monsoonal circulation also makes some contribution to anion concentrations, but pollution associated with human
activities makes a very slight contribution in study area. The chemical characteristics of two snowpits are different owing
to the difference of deposition mechanism and local environment in different altitudes. 相似文献
113.
通过对内蒙古额济纳盆地小狐山剖面沉积物中酸溶组分稀土元素含量及其相关指标、分布模式的分析,讨论了剖面中稀土元素指标δCe-ΣREE与沉积相、沉积环境之间的关系。分析结果表明剖面沉积物酸溶组分中稀土元素丰度均值为7.24μg/g(不包括Y),其中LREE含量占稀土总量的88.67%; 且各层的稀土分布模式均为轻稀土适度富集缓右倾斜型、Eu呈负异常模式,但各相位地层的LREE富集程度与分配模式存在差异。由于小狐山剖面中沉积地层的自身岩性、沉积粒径、矿物结构组成以及气候环境变化等因素均可能会引起REE分异。因此,通过δCe-ΣREE图并结合三次回归曲线,可以很好地将不同沉积相得物质有效的区分开来。小狐山剖面除极少数的几个样品(水下沉积砂)之外,其余的均落在三次多项式回归曲线上部; 而风成砂层则几乎全部落在回归曲线之下; 此外,对于风沙-河流作用下的混合样品也有较好识别,河流过渡相的样品则分布在曲线上或与之相邻近。此研究结果得到了柴达木贝壳堤沉积物的REE数据的验证,运用此方法可以为直观的判别剖面中的不同沉积相,并为定量化划分地层提供依据。 相似文献
114.
Wu Xiangjie Pang Xiong Shi Hesheng He Min Shen Jan Zhang Xiangtao Hu Dengke 《中国地质大学学报(英文版)》2009,20(1)
To study the deep dynamic mechanism leading to the difference in rifting pattern and basin structure from shelf to oceanic basin in passive continental margin,we constructed long geological sections across the shelf,slope and oceanic basin using new seismic data.Integrated gravity-magnetic inversion and interpretation of these sections were made with the advanced dissection method.Results show that the basement composition changes from intermediate-acid intrusive rocks in the sheff to intermediate-basic rocks in the slope.The Moho surface shoals gradually from 31 km in the sheff to 22.5 km in the uplift and then 19 km in the slope and finally to 13 km in the oceanic basin.The crust thickness also decreases gradually from 30 km in the northern fault belt to 9 km in the oceanic basin.The crustal stretching factor increases from the shelf toward the oceanic basin,with the strongest extension under the sags and the oceanic basin.The intensity of mantle upwelling controlled the style of basin structures from sheff to oceanic basin.In the Zhu 1 depression on the shelf,the crust is nearly normal,the brittle and cold upper crust mainly controlled the fault development;so the combinative grabens with single symmetric graben are characteristic.In the slope,the crust thinned with a large stretching factor,affected by the mantle upwelling.The ductile deformation controlled the faults,so there developed an asymmetric complex graben in the Baiyun (白云) sag. 相似文献
115.
采用MAP-CGE模型,模拟了我国水泥行业实施低碳水泥标准对不同生产工艺产出、能耗及污染排放的影响,测算了对其边际减排成本和均衡价格的影响,分析了对不同污染物的协同减排效果。模拟结果表明:实施低碳水泥标准有利于水泥生产工艺的升级换代,并有助于水泥行业节能减排;在现有技术水平下,水泥行业在减排1 t CO2的同时将带来约1.17 kg的SO2减排量和4.44 kg的NOx减排量;实施低碳水泥标准对于水泥行业控制NOx排放很有利;但水泥行业也需承担减排成本并导致其均衡价格的小幅上升。 相似文献
116.
Slope aspect has significant effect on the development and distribution of montane forest,especially in arid and semiarid regions.This paper,using SPOT5 images and 1:50,000 DEM,digitally extracts and analyzes the spatial information of montane coniferous forest(mainly Qinghai spruce),and thereby explores how the upper and lower limits and the altitudinal range of coniferous forest vary and how the area of coniferous forest is related with annual insolation with all aspects in the Helan Mountains.The results show that: 1) In the eastern flank,the lower limit of coniferous forest is between 1,600 m and 2,000 m a.s.l.,and the upper limit between 2,800 m and 3,000 m a.s.l.;in the western flank,the lower limit of coniferous forest is between 2,000 m and 2,300 m a.s.l.,and the upper limit between 2,800 m and 3,100 m a.s.l.2) The altitudinal ranges of coniferous forest are 806~1,435 m,438~1,140 m for eastern flank and western flank,respectively.3) The area of coniferous forest takes on a normal distribution with aspect,and it has a close relationship with annual insolation.This distribution model developed in this paper quantitatively reveals the significant effect of slope aspect on the distribution of coniferous forest in arid and semi-arid land. 相似文献
117.
Six new chrysophycean stomatocysts ornamented with reticulum from the Great Xing’an Mountains, China
Six new chrysophycean stomatocysts ornamented with reticulum were illustrated based on SEM observation. They were described following the guidelines of the International Statospore Working Group (ISWG). All samples were collected from the Great Xing’an Mountains, China. Their taxonomic characteristics and habitats were described to provide new information on the biodiversity of chrysophycean stomatocysts. As is common with many morphotypes, their biological affinities remain unknown. 相似文献
118.
利用LA-ICP-MS锆石U-Pb法,测得与成矿有关的青海祁漫塔格地区虎头崖矿床Ⅵ矿带花岗岩的成岩年龄为(233.6±1.8) Ma(MSWD=1.2,n=17)。地球化学特征显示:花岗岩属高钾钙碱性、弱过铝质花岗岩;样品的稀土元素组成以总体右倾,轻、重稀土分异明显和具明显的负铕异常为特征;微量元素具有富集Rb、Th、U、La、Nd等大离子亲石元素,亏损Ba、Sr、Nb、P、Ti等元素的特点。Sr-Nd同位素组成特征显示,花岗岩的源区可能是富集岩石圈地幔。初步研究认为,虎头崖矿床Ⅵ矿带花岗岩可能形成于中、晚三叠世碰撞后碰撞的构造背景下。 相似文献
119.
Nowadays, the Fe-C coprecipitate mechanism is recognized by more and more scholars and becomes the hot topic in the environmental science. On the basis of discussing the interaction between iron oxide and organic matter, and the adsorption research progress of Fe-C complexes on heavy metals, the immobilization potential of Fe-C complexes on heavy metals in polluted soil were illustrated. The surface properties and physical characterizations of iron oxide are changed regularly with the interaction of organic matter, which lead to the higher adsorption capacity of Fe-C complexes in contrast to single iron oxide. Besides, the influences of pH values, organic matter types and surface properties of iron oxides on the adsorption capacity of Fe-C complexes on heavy metals were discussed. The excellent adsorption performance of Fe-C complexes in certain conditions will provide important theoretical basis for contaminated soil remediation. 相似文献
120.
全面分析了气候变化给企业带来的机遇与挑战。全球契约的"关注气候"倡议为企业响应全球号召应对气候变化带来了机遇,全球契约是全球企业共同应对气候变化、实现企业社会责任和树立企业形象的良好平台。另外,通过调查研究分析了中国民营企业应对气候变化的现状,并提出了相关政策建议。 相似文献