南京市降水化学特征及其来源研究   总被引：4，自引：0，他引：4       下载免费PDF全文

张泽锋  沈利娟  朱彬  岳江  王红磊  张秋晨 《大气科学学报》2015,38(4):473-482

为了解南京江北地区降水化学特征,分析了2011年3—6月共25个降水日的109个降水样品中的主要水溶性离子,并利用后向轨迹模式探讨了降水气团来源.结果表明:1)南京地区3—6月降水主要受南、北2种气团影响,北方气团降水的主要离子浓度高于南方气团降水.2)海盐示踪法和相关性分析显示,降水中NO₃^-和SO₄^2-主要来自燃煤、工业排放和汽车尾气;Ca²⁺主要来自地壳源;Cl^-主要来自海洋;海洋源和陆源对Mg²⁺和K⁺都有贡献,Mg²⁺的陆源贡献大于海洋源贡献,K⁺受海洋源的影响程度要低于Mg²⁺.3)南、北气团初期降水的各离子浓度高于总降水的各离子浓度,且初期降水的主要离子的富集系数高于总降水.这说明在降水初始阶段,雨水对南京大气中污染物(气态污染物和颗粒物)的云下冲刷去除作用较强,降水的离子浓度最高,局地源对降水离子的贡献较明显.  相似文献   

Deep convective clouds over the northern Pacific and their relationship with oceanic cyclones     

Mingjian Yi  Yunfei Fu  Peng Liu  Zhixia Zheng 《大气科学进展》2015,32(6):821-830

Based on combined Cloud Sat/CALIPSO detections, the seasonal occurrence of deep convective clouds(DCCs) over the midlatitude North Pacific(NP) and cyclonic activity in winter were compared. In winter, DCCs are more frequent over the central NP, from approximately 30°N to 45°N, than over other regions. The high frequencies are roughly equal to those occurring in this region in summer. Most of these DCCs have cloud tops above a 12 km altitude, and the highest top is approximately 15 km. These wintertime marine DCCs commonly occur during surface circulation conditions of low pressure, high temperature, strong meridional wind, and high relative humidity. Further, the maximum probability of DCCs,according to the high correlation coefficient, was found in the region 10°–20° east and 5°–10° south of the center of the cyclones. The potential relationship between DCCs and cyclones regarding their relative locations and circulation conditions was also identified by a case study. Deep clouds were generated in the warm conveyor belt by strong updrafts from baroclinic flows. The updrafts intensified when latent heat was released during the adjustment of the cyclone circulation current. This indicates that the dynamics of cyclones are the primary energy source for DCCs over the NP in winter.  相似文献   

Structures and characteristics of the windy atmospheric boundary layer in the South China Sea region during cold surges     

CHENG Xue-Ling  HUANG Jian  WU Lin  ZENG Qing-Cun 《大气科学进展》2015,32(6):772-782

An observational analysis of the structures and characteristics of a windy atmospheric boundary layer during a cold air outbreak in the South China Sea region is reported in this paper. It is found that the main structures and characteristics are the same as during strong wind episodes with cold air outbreaks on land. The high frequency turbulent fluctuations(period<1 min) are nearly random and isotropic with weak coherency, but the gusty wind disturbances(1 min相似文献   

Invasion and morphological variation of the non-indigenous barnacle Chthamalus challengeri (Hoek, 1883) in Yangshan Port and its surrounding areas     

Liu  Yan  Xue  Junzeng  Lin  Junda  Wu  Huixian 《中国海洋大学学报(英文版)》2015,14(3):575-583

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威海市环翠区地下水环境质量评价          下载免费PDF全文

衣伟虹  王松涛  吴振  宋委 《山东国土资源》2015,31(12)

在威海市环翠区地下水调查研究的基础上,选取10项因子,采用单项组分评价和综合评价相结合的方法对区内浅层地下水进行分析评价。结果显示,区内大部分地区水质较好,部分地区由于受人类活动等的影响,导致水质变差,其主要超标因子有硫酸盐、硝酸盐、氯化物、总硬度等。  相似文献   

海洋三维遥感与海洋剖面激光雷达     

唐军武  陈戈  陈卫标  赵朝方  贺岩  吴松华  刘秉义  毛志华  何惠馨  杨杰  陈树果  胡连波  何兴道  史久林  郑永超  刘建强  林明森  吴立新  郭华东  蒋兴伟  潘德炉  顾逸东 《遥感学报》2021,25(1):460-500

本文从海洋与气候变化等重大前沿科学与应用对空间海洋观测系统的需求出发,基于当前国内外空间激光技术水平与前期海洋激光遥感的探索,提出了海洋遥感从二维向三维发展的紧迫性,并将海洋剖面探测激光雷达作为未来“海洋三维遥感”的主要技术手段。本文对近50年国内外激光海洋剖面探测技术的理论与应用、基础性关键探测机理问题,尤其是近10年来的试验性探索及其在多个海洋科学问题中的应用进行了综述。结合中国自主“观澜号”海洋科学卫星计划中海洋剖面探测激光雷达的系统论证与指标要求,提出了未来海洋剖面探测激光雷达发展路线图建议以及中国有望率先在空间海洋剖面激光探测领域取得突破的设想。  相似文献   

长江口外海域表层沉积物微量元素地球化学特征   总被引：1，自引：1，他引：0  

蓝先洪  张志殉  李日辉  王中波  陈晓辉  侯方辉 《现代地质》2011,25(6)

对采自长江口外海域187个表层沉积物的25个微量元素含量进行了标准差系数、相关分析及R型因子分析,探讨了微量元素的来源和分布特征。长江口外海域沉积物微量元素Li、V、Cr、Co、Ni、Ga、Cu、Zn、Th和Rb分布基本相似;Sr分布与Li、Cu、Pb、Zn、Th和Rb相反;研究区东南部Sr分布与生物作用有明显关系;Cd和Mo分布与粒度之间的相关性较差,主要受氧化还原环境的控制;Zr分布反映了长江物源的影响。相关分析和R型因子分析结果表明,沉积作用、粒度控制效应、海洋生物作用、氧化还原环境和源区地质背景等对长江口外海域表层沉积物中微量元素分布起着主要控制作用。  相似文献   

Geochemical Stratigraphy and Microvertebrate Assemblage Sequences across the Silurian/Devonian Transition in South China     

ZHAO Wenjin  WANG Nianzhong  ZHU Min  Ulrich MANN  Ulrich HERTEN  Andreas LüCKE 《《地质学报》英文版》2011,85(2):340-353

Carbon isotope (δ13Corg) analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and Lower Devonian and reaching peak values as heavy as ?25.2‰ (Xishancun) and ?19.9‰ (Putonggou) in the lowermost Lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti (only in Putonggou Section and together with Protathyris-Lanceomyonia brachiopod fauna). These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary (SDB) at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point (GSSP) in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the Liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation (between sample QX-20 and sample QX-21) in the Xishancun Section and the lower part of the Xiaputonggou Formation (between sample ZP-09 and sample ZP-10) in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with non-marine deposits.  相似文献   

江西武山花岗闪长斑岩中黑云母成分特征及其成岩成矿意义   总被引：4，自引：0，他引：4  

东前  杜杨松  曹毅  庞振山  宋林旭  郑震 《矿物岩石》2011,31(2)

江西武山花岗闪长斑岩与矽卡岩铜矿在成因上密切相关,通过对其中的黑云母进行的岩相学观察和详细的矿物化学分析来探讨黑云母的形成条件及其成岩成矿意义。电子探针分析结果表明,武山花岗闪长斑岩中的黑云母富镁贫铁低铝高钛,属镁质黑云母。其AlⅥ为0.03~0.19,w(ΣFeO)/w(ΣFeO+MgO)为0.531~0.567,w(MgO)为12.80%~14.06%,指示武山花岗闪长斑岩属壳幔混源的I型花岗岩。黑云母结晶的温度为720℃~750℃,logfO2为-11.6~-12.5,压力为86 MPa~103 MPa,对应的侵位深度为2.84 km~3.39 km,表明该岩体形成于相对高温较浅环境,具有较大成矿潜力,有利于武山铜矿的形成。  相似文献   

川东北地区海相烃源岩中单质硫的定性与定量分析     

张中宁  刘文汇  夏燕青  腾格尔  王作栋  高波  张殿伟  邱军利 《矿物岩石》2011,31(3)

利用定性与定量分析手段,研究了川东北地区各类海相烃源岩中的单质硫及其地球化学特征。定性分析表明,该区海相烃源岩中的单质硫具有八硫环状结构和六硫状环结构两种晶体构型,由S8和S6两种同素异形体组成,其中S8具有相对较高的丰度。定量分析表明,该区海相烃源岩中的单质硫含量为0.91×10-6～375.88×10-6,具有很宽的分布范围,并且随着烃源岩分布区域、地层时代以及岩性的不同而发生明显变化,表现出强烈的非均质性分布特征。该区海相烃源岩中单质硫含量与有机碳含量之间存在正相关关系,说明单质硫主要发育在富有机质沉积的层段中。通过单质硫含量与总硫含量对比分析,间接证明了川东北地区各类海相烃源岩中赋存有丰富的有机含硫化合物。  相似文献