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中国南方红壤生态系统面临的问题及对策 被引量:265
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作者 赵其国 黄国勤 马艳芹 《生态学报》 CAS CSCD 北大核心 2013年第24期7615-7622,共8页
南方红壤对于我国农业乃至整个国民经济的持续发展和人民生活水平的迅速提高发挥了重要作用,但由于红壤性质上的酸、瘦、粘等弱点,分布区域降水时空不均匀,以及不合理开发利用造成的水土流失、土壤退化、土壤污染等,导致红壤地区的生态... 南方红壤对于我国农业乃至整个国民经济的持续发展和人民生活水平的迅速提高发挥了重要作用,但由于红壤性质上的酸、瘦、粘等弱点,分布区域降水时空不均匀,以及不合理开发利用造成的水土流失、土壤退化、土壤污染等,导致红壤地区的生态环境恶化,红壤资源潜在的生产能力得不到应有的发挥,使整个地区农业及经济持续发展受到严重影响。目前,中国南方红壤生态系统面临水土流失、土壤酸化、肥力退化、季节性干旱、土壤污染、生物退化、石漠化及土地沙化、耕地面积缩减和系统功能衰减等问题。针对上述问题,在综合治理措施上必须提高认识,调整农业结构,优化耕作制度,大力发展立体农业,防治水土流失和土壤污染,改良土壤,培肥地力,重建红壤区植被生态系统,建立和完善红壤预警,从而保证南方红壤生态系统的持续稳定健康发展。 展开更多
关键词 红壤 生态系统 问题 对策 南方
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中国南方喀斯特生态系统面临的问题及对策 被引量:94
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作者 熊康宁 池永宽 《生态经济》 CSSCI 北大核心 2015年第1期23-30,共8页
中国南方喀斯特生态系统具有两个极端的景观形式,既有贵州荔波、重庆武隆等原始喀斯特生态系统,同时又存在遭受严重人为干扰的次生喀斯特生态系统。喀斯特地区受自然条件的影响和人类社会经济活动的干扰,生态系统十分脆弱,并有逐渐恶化... 中国南方喀斯特生态系统具有两个极端的景观形式,既有贵州荔波、重庆武隆等原始喀斯特生态系统,同时又存在遭受严重人为干扰的次生喀斯特生态系统。喀斯特地区受自然条件的影响和人类社会经济活动的干扰,生态系统十分脆弱,并有逐渐恶化的趋势。我国南方喀斯特生态系统的脆弱性集中体现在:土壤脆弱性、水文脆弱性、植被脆弱性、人文环境脆弱性等方面。对喀斯特生态系统利用不当将影响我国整个生态系统稳定和可持续发展。当前我国南方喀斯特生态系统面临的主要问题集中表现在:人口压力大,耕地问题,水土流失,土壤退化,石漠化,生物多样性退化,生态系统功能衰退,季节性干旱与洪涝,滑坡、泥石流等地质灾害频发,环境污染等问题。针对上述问题,采取控制人口数量、提高人口质量,保护与改良耕地,发展立体生态农业,优化产业结构与布局,划分石漠化等级、综合治理,水土流失综合防治,改善能源结构,治理环境污染,重建喀斯特生物多样性,建立灾害预警机制等对策,保证南方喀斯特生态系统的健康稳定可续发展。 展开更多
关键词 南方 喀斯特 生态系统 脆弱性 问题 对策
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中国妇女宫颈癌组织中人乳头瘤病毒感染及其地理分布的调查 被引量:67
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作者 李洁 刘宝印 +16 位作者 zur Hausen H 王宏 杨学志 李力 刘文 刘洪隐 陆克昭 刘旭 牛春燕 裴润芳 苏钟浦 王言贵 董继华 张桂宁 刘春杰 许吉林 林毓纯 《中华实验和临床病毒学杂志》 CAS CSCD 1996年第1期50-55,共6页
应用核酸印迹技术(Southern blot),对我国十四省市自治区的1455例来源宫颈癌、官颈不典型增生、宫颈湿疣和正常宫颈组织,进行人乳头瘤病毒(HPV)感染的型别检测,并分析了其型别地理分布特点。结果发现,815例宫颈癌组织 HPV 总检出率53.5%... 应用核酸印迹技术(Southern blot),对我国十四省市自治区的1455例来源宫颈癌、官颈不典型增生、宫颈湿疣和正常宫颈组织,进行人乳头瘤病毒(HPV)感染的型别检测,并分析了其型别地理分布特点。结果发现,815例宫颈癌组织 HPV 总检出率53.5%,其中 HPV16和58型检出率最高,分别是31.9%和7.6%,HPV6/11和18型的检出率为2.3%和1.0%。而在195例宫颈上皮不典型增生中,HPV 总检出率为25.1%,16/58型和6/11型的检出率分别为4.6%、15.9%。206例宫颈湿疣中,HPV 检出率40.8%,6/11型最高,达33.5%。239例正常宫颈组织中,仅检出1例 HPV16型,5例6/11型。提示:我国宫颈癌 HPV 感染以16、58型为主,18型少见。还发现,北方地区的宫颈癌组织中,HPV 感染以16型为主;南方省份长江中下游地区,HPV58 型检出率明显增高,几乎和 HPV16型持平;沿海地区不明的相关型呈上升趋势。提示我国宫颈癌 HPV 感染的型别,可能存在"移行"的地理分布特点。 展开更多
关键词 宫颈肿瘤 人乳头瘤病毒 印迹法 DNA
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Study of liver cirrhosis over ten consecutive years in Southern China 被引量:76
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作者 Xing Wang Shang-Xiong Lin +4 位作者 Jin Tao Xiu-Qing Wei Yuan-Ting Liu Yu-Ming Chen Bin Wu 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13546-13555,共10页
AIM: To investigate the etiology and complications of liver cirrhosis (LC) in Southern China.
关键词 Liver cirrhosis EPIDEMIOLOGY ETIOLOGY COMPLICATION Hepatocellular carcinoma southern China
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SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications 被引量:57
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作者 PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China +1 位作者 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, Beijing 100037, China 4. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 《Science China Earth Sciences》 SCIE EI CAS 2006年第10期1032-1042,共11页
The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, weste... The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province. 展开更多
关键词 SHRIMP zircon U-Pb dating Middle Triassic Lincang GRANITIC batholith Manghuai Formation rhyolite southern Lancangjiang.
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新生儿肺炎死亡病例中B族链球菌的检测 被引量:53
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作者 邓江红 姚开虎 +6 位作者 胡惠丽 俞桑洁 高薇 伏利兵 何乐健 Alexander Dmitriev 杨永弘 《中华儿科杂志》 CAS CSCD 北大核心 2006年第11期850-854,共5页
目的对北京儿童医院新生儿肺炎死亡病例进行B族链球菌(GBS)回顾性检测,旨在初步揭示GBS感染在新生儿重症肺炎中的地位。方法收集200例1953年到2004年间新生儿肺炎死亡病例(研究组)和34例非感染性疾病新生儿死亡病例(对照组)的尸检病理标... 目的对北京儿童医院新生儿肺炎死亡病例进行B族链球菌(GBS)回顾性检测,旨在初步揭示GBS感染在新生儿重症肺炎中的地位。方法收集200例1953年到2004年间新生儿肺炎死亡病例(研究组)和34例非感染性疾病新生儿死亡病例(对照组)的尸检病理标本,提取石蜡组织DNA,通过PCR和Southernblot技术检测GBS特异性基因片断cfb基因。同时对所选病例的临床资料进行复习。结果(1)研究组200例中,PCR对GBS检出率为26%,Southernblot检出率为65%,检出率均明显高于对照组(PCR3%,χ2=8.82,P<0.01;Southernblot,18%,χ2=26.77,P<0.01)。(2)研究组中,年龄小于7d的病例(早发型)103例,年龄大于7d的病例(晚发型)97例,小于7d的患儿GBS检出率明显高于大于7d的患儿,其中PCR检出率在前者为37%,后者为13%(χ2=15.537,P<0.01),Southernblot检出率在前者为72%,后者为52%(χ2=4.37,P<0.05)。早发型阳性病例中,39%为早产儿(29/74)。(3)研究组中,75例有完整临床资料,其中35例可查到一项或多项与GBS感染有关的危险因素,如早产,低体重,胎膜早破,羊水异常等,GBS检测结果均为阳性。阳性病例中,早发型最常见的表现有青紫、窒息,呼吸困难,晚发型最常见的表现有咳喘,呼吸困难。对照组中,1例PCR检测阳性者患恶性畸胎瘤,其他5例仅Southernblot检测阳性者分别为核黄疸、肝癌、先天性无肛合并膀胱尿道瘘、新生儿自然出血、先天性低位无肛合并直肠会阴瘘患者。结论GBS是新生儿肺炎死亡病例中的重要病原,尤其在早发型肺炎病例中GBS感染占很大比重。Southernblot是在石蜡标本中检测GBS的较为敏感方法。 展开更多
关键词 链球菌 天乳 婴儿 新生 肺炎 细菌性 聚合酶链反应 ET迹法 DNA
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藏南也拉香波早渐新世富钠过铝质淡色花岗岩的成因机制及其构造动力学意义 被引量:53
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作者 高利娥 曾令森 +1 位作者 刘静 谢克家 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第9期2289-2302,共14页
藏南也拉香波穹隆位于近东西向展布的北喜马拉雅片麻岩穹隆(NHGD)最东端,主要由石榴角闪岩、石榴石云母片麻岩、二云母花岗岩和淡色花岗岩组成。SHRIMP锆石U/Pb定年结果表明也拉淡色花岗岩的结晶年龄为35.3±1.1Ma,明显老于位于该... 藏南也拉香波穹隆位于近东西向展布的北喜马拉雅片麻岩穹隆(NHGD)最东端,主要由石榴角闪岩、石榴石云母片麻岩、二云母花岗岩和淡色花岗岩组成。SHRIMP锆石U/Pb定年结果表明也拉淡色花岗岩的结晶年龄为35.3±1.1Ma,明显老于位于该穹隆以西类似的淡色花岗岩(年龄普遍<25Ma)。全岩元素和Sr-Nd同位素测试结果揭示:(1)也拉香波淡色花岗岩为过铝质富钠花岗岩;(2)与片麻岩相似,也拉香波淡色花岗岩富集大离子亲石元素(LILE,如K,Sr,Rb和Ba),但亏损Ti,Y,Yb,Sc和Cr;(3)和片麻岩或角闪岩相比,也拉香波淡色花岗岩同时亏损LREE和HREE,但与HREE相比,LREE相对富集;(4)在Sr-Nd同位素系统特征上,淡色花岗岩初始Sr同位素比值与角闪岩的相当,在0.711949~0.719344之间;但远小于片麻岩。而Nd同位素组成在片麻岩和角闪岩之间,在-8.9~-15.0之间。以石榴角闪岩和片麻岩为瑞元,简单混合计算表明:由石榴角闪岩为主和片麻岩为辅组成的混合源区发生部分熔融作用,各自产生的熔体进行不同程度的混合,可形成类似于也拉香波淡色花岗岩成分的岩浆,其中角闪岩的部分熔融起主要作用。使用Zr在岩浆中的饱和浓度温度计得出岩浆的平均温度为673℃,在此温度下,变泥质片麻岩在高压(~10kbar)条件下的水致部分熔融和角闪岩部分熔融都可形成也拉过铝质富钠淡色花岗岩,但角闪岩的脱水部分熔融起主导作用。在地壳增厚条件下,下地壳角闪岩的部分熔融可能是导致喜玛拉雅造山带从缩短增厚向伸展垮塌转换的主要因素之一。 展开更多
关键词 藏南 香波 渐新世 铝质 淡色花岗岩 成因机制 构造动力学 southern 石榴角闪岩 片麻岩穹隆 部分熔融 partial melting extensional deformation Sr-Nd同位素 HOWEVER 岩浆 温度 混合 SHRIMP 云母花岗岩
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转几丁质酶和β-1,3-葡聚糖酶基因提高棉花对枯萎病和黄萎病的抗性 被引量:44
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作者 程红梅 简桂良 +7 位作者 倪万潮 杨红华 王志兴 孙文姬 张保龙 王晓峰 马存 贾士荣 《中国农业科学》 CAS CSCD 北大核心 2005年第6期1160-1166,共7页
枯、黄萎病是世界棉花生产中的两大重要病害。传统育种缺乏抗源,几丁质酶和β-1,3-葡聚糖酶是植物防御体系中的两种防卫因子,两者之间存在协同增效作用。据此构建了4个单价和2个双价基因(分别定位于细胞内或细胞外)的植物表达载体,通过... 枯、黄萎病是世界棉花生产中的两大重要病害。传统育种缺乏抗源,几丁质酶和β-1,3-葡聚糖酶是植物防御体系中的两种防卫因子,两者之间存在协同增效作用。据此构建了4个单价和2个双价基因(分别定位于细胞内或细胞外)的植物表达载体,通过花粉管通道法转化棉花,经PCR和Southern杂交检测以及1996~2000年温室及病圃多代筛选鉴定,已培育出对枯、黄萎病抗性提高的转基因棉花株系。将抗病基因导入国产抗虫棉品种GK19中,还获得了兼抗病、虫的转基因优系。 展开更多
关键词 几丁质酶 黄萎病 葡聚糖酶基因 β-1 抗性 枯萎病 southern 3-葡聚糖酶 协同增效作用 植物表达载体 花粉管通道法 2000年 转基因棉花 抗虫棉品种 棉花生产 传统育种 防御体系 双价基因 筛选鉴定 杂交检测 GK19 基因导入
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半夏凝集素基因(pta)导入水稻及其表达的初步研究 被引量:37
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作者 张红宇 吴先军 +3 位作者 唐克轩 汪旭东 孙小芬 周开达 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2003年第11期1013-1019,共7页
半夏凝集素基因是一种有重要价值的抗虫基因。利用RACE PCR技术克隆出半夏凝集素 (pta)基因 ,并将它构建到载体pCAMBIA1 30 5中形成双元载体 (含pta基因和hpt基因 )。利用农杆菌介导法将pta基因转入粳稻品种鄂宜 1 0 5、中花 1 2和籼稻... 半夏凝集素基因是一种有重要价值的抗虫基因。利用RACE PCR技术克隆出半夏凝集素 (pta)基因 ,并将它构建到载体pCAMBIA1 30 5中形成双元载体 (含pta基因和hpt基因 )。利用农杆菌介导法将pta基因转入粳稻品种鄂宜 1 0 5、中花 1 2和籼稻品种E优 5 32成熟胚诱导的愈伤组织中。通过PCR检测 ,从 1 1 7株T0 代再生植株中筛选出 36株 (其中鄂宜 1 0 5、中花 1 2、E优 5 32分别为 1 9株、7株、1 0株 )转基因植株。对这些转基因后代植株进行Southernblot分析和RT PCR分析表明 :pta基因已经整合到受体细胞基因组中 ,并在转录水平上得到了有效表达。通过对转基因后代的遗传分析 ,成功地从T1 代表现为 1∶2∶1孟德尔分离的分离群体中筛选出 7个独立转基因水稻纯系 (其中包括 4个鄂宜 1 0 5、1个中花 1 2和 2个E优 5 32转基因纯系 )。对这 7个独立转基因水稻T2 代纯系进行褐飞虱生物抗性鉴定和田间隔离喂养实验 ,结果显示 ,这些转基因纯系对褐飞虱的存活率和发育进度均有显著的抑制作用。同时 ,实验结果还表明 2~ 5mg L的 2 ,4 D是愈伤组织诱导和生长的必需条件 ,而且受体的基因型对愈伤组织诱导率和转化频率均有显著影响 ,在同等条件下 。 展开更多
关键词 半夏凝集素基因 抗虫 转基因水稻 southern BLOT RT-PCR
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单管多重PCR快速检测中国人三种常见缺失型α-地中海贫血基因 被引量:40
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作者 周玉球 张永良 +4 位作者 李莉艳 李文典 莫秋华 郑勤 徐湘民 《中华医学遗传学杂志》 CAS CSCD 北大核心 2005年第2期180-184,共5页
目的 建立一种简单快速、准确可靠、经济实用的检测常见缺失型α-地中海贫血(α-地贫)突变(- - SEA、- α3.7和- α4 .2 )的单管多重PCR技术以用于α-地贫的分子筛查和产前诊断。方法 采用gap- PCR方案设计4组PCR引物并对PCR反应条件... 目的 建立一种简单快速、准确可靠、经济实用的检测常见缺失型α-地中海贫血(α-地贫)突变(- - SEA、- α3.7和- α4 .2 )的单管多重PCR技术以用于α-地贫的分子筛查和产前诊断。方法 采用gap- PCR方案设计4组PCR引物并对PCR反应条件进行系统优化以扩增代表这3种地贫和α2 基因存在的特异性DNA片段。此外,还设计1对引物扩增L IS1基因3′-端非翻译区片段作为整个PCR体系扩增成功与否的内在对照。采用盲法分析对该技术的特异性、准确性和可靠性进行评价并应用于产前分子诊断中。结果 所建的单管多重PCR技术成功地检出这3种常见缺失型α-地贫突变的纯合子、杂合子和双重杂合子。正常人出现L IS1和α2 基因特异扩增片段,而- - SEA、- α3.7和- α4 .2杂合子除了出现正常人的2条扩增带外,还分别出现1条指示这些突变存在的特异性扩增片段。盲法分析结果显示,该技术对α-珠蛋白基因型经过Southern印迹法或DNA直接测序确证的DNA标本的诊断准确性达到10 0 % ,并被成功地应用于9个重症α-地贫高风险家庭的产前诊断中。结论 该技术可准确、快速地检测- - SEA、-α3.7和-α4 .2 3种常见缺失型α-地贫突变,且具有经济和实用的优点,非常适合于α-地贫的大人群分子筛查和临床样品的基因诊断。 展开更多
关键词 α-地中海贫血基因 快速检测 缺失型Α-地中海贫血 多重PCR技术 southern DNA直接测序 中国 产前分子诊断 产前诊断 分子筛查 扩增片段 DNA片段 PCR引物 双重杂合子 诊断准确性 DNA标本 特异性 经济实用 系统优化 反应条件
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太行山南段符山高镁闪长岩的成因——拆沉陆壳物质熔融的熔体与地幔橄榄岩反应的结果 被引量:40
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作者 许文良 杨德彬 +1 位作者 裴福萍 于洋 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期1947-1961,共15页
本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。... 本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。含橄榄岩包体的寄主岩——角闪闪长岩中的锆石可划分为两种:一是代表寄主岩浆结晶的锆石:内部结构均匀、呈条带状吸收、自形-半自形晶形,具有较高的Th/U比值(1.10~4.08),其^(206)Pb/^(238)U年龄介于123~128Ma之间,12个点的加权平均值为125±1Ma,这表明岩体的形成时代为早白垩世;二是捕获或继承锆石:具有核边结构、吸收程度不均匀、呈浑圆状和自形-半自形两种,它们的Th/U比值介于0.32~2.03之间,构成了3组^(207)Pb/^(206)Pb加权平均年龄:2503±11Ma、2181±26Ma和1778±36Ma。该类岩石的SiO_2和MgO含量分别介于56.69%~59.21%和3.60%~6.33%之间;且以高Mg~#(0.51~0.64)、富Na(Na_2O/K_2O大于1)、高Cr(93.1×10^(-6)~420×10^(-6))、Ni(35.1×10^(-6)~137×10^(-6))为特征。该类岩石强烈富集轻稀土元素和大离子亲石元素、明显亏损高场强元素,(^(87)Sr/^(86)Sr)_i、ε_(Nd)(t)值和(^(206)Pb/^(204)Pb)_i分别变化于0.70581~0.70641、-8.30~-16.56和17.052~17.512之间。综合上述特征,同时结合地慢橄榄岩包体的特征和古元古代捕获锆石的大量存在,认为符山高镁闪长岩的原始岩浆起源于拆沉陆壳物质的部分熔融,其后经历了与地幔橄榄岩的反应过程。 展开更多
关键词 山南 高镁闪长岩 成因 物质 熔融 熔体 地幔橄榄岩 橄榄岩包体 岩反应 结果 North China Craton central southern continental crust partial melting peridotite XENOLITHS high field strength rare earth elements crystallization time lithospheric mantle
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Variational iteration method for solving the mechanism of the Equatorial Eastern Pacific El Nino-Southern Oscillation 被引量:35
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作者 莫嘉祺 王辉 +1 位作者 林万涛 林一骅 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第4期671-675,共5页
A class of coupled system for the E1 Nifio-Southern Oscillation (ENSO) mechanism is studied. Using the method of variational iteration for perturbation theory, the asymptotic expansions of the solution for ENSO mode... A class of coupled system for the E1 Nifio-Southern Oscillation (ENSO) mechanism is studied. Using the method of variational iteration for perturbation theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic behaviour of solution for corresponding problem is considered. 展开更多
关键词 nonlinear method of variational iteration perturbation theory El Nino- southern Oscillation model
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How many sutures in the southern Central Asian Orogenic Belt:Insights from East Xinjiang-West Gansu(NW China)? 被引量:33
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作者 Wenjiao Xiao Chunming Han +7 位作者 Wei Liu Bo Wan Ji'en Zhang Songjian Ao Zhiyong Zhang Dongfang Song Zhonghua Tian Jun Luo 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第4期525-536,共12页
How ophiolitic mèlanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth.The Chinese Altay,East junggar,Tianshan,and Beishan belts of the southern Central A... How ophiolitic mèlanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth.The Chinese Altay,East junggar,Tianshan,and Beishan belts of the southern Central Asian Orogenic Belt(CAOB) in Northwest China,offer a special natural laboratory to resolve this puzzle.In the Chinese Altay,the Erqis unit consists of ophiolitic melanges and coherent assemblages,forming a Paleozoic accretionary complex.At least two ophiolitic melanges(Armantai,and Kelameili) in East Junggar,characterized by imbricated ophiolitic melanges,Nb-enriched basalts,adakitic rocks and volcanic rocks,belong to a Devonian-Carboniferous intra-oceanic island arc with some Paleozoic ophiolites,superimposed by Permian arc volcanism.In the Tianshan,ophiolitic melanges like Kanggurtag,North Tianshan,and South Tianshan occur as part of some Paleozoic accretionary complexes related to amalgamation of arc terranes.In the Beishan there are also several ophiolitic melanges,including the Hongshishan,Xingxingxia-Shibangjing,Hongliuhe-Xichangjing,and Liuyuan ophiolitic units.Most ophiolitic melanges in the study area are characterized by ultramafic,mafic and other components,which are juxtaposed,or even emplaced as lenses and knockers in a matrix of some coherent units.The tectonic settings of various components are different,and some adjacent units in the same melange show contrasting different tectonic settings.The formation ages of these various components are in a wide spectrum,varying from Neoproterozoic to Permian.Therefore we cannot assume that these ophiolitic melanges always form in linear sutures as a result of the closure of specific oceans.Often the ophiolitic components formed either as the substrate of intra-oceanic arcs,or were accreted as lenses or knockers in subduction-accretion complexes.Using published age and paleogeographic constraints,we propose the presence of (1) a major early Paleozoic tectonic boundary that separates the Chinese Altay-East Junggar multiple subduction system 展开更多
关键词 Major suture Paleogeographic separation Accretionary complex Intra-oceanic arc southern CAOB
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Re-Os isotope dating of molybdenites in the Huang-shaping Pb-Zn-W-Mo polymetallic deposit, Hunan Province, South China and its geological significance 被引量:30
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作者 YAO JunMing HUA RenMin +3 位作者 QU WenJun QI HuaWen LIN JinFu DU AnDao 《Science China Earth Sciences》 SCIE EI CAS 2007年第4期519-526,共8页
The large-scale Huangshaping Pb-Zn-W-Mo polymetallic deposit is located in the central Nanling min- eralization zone, South China. Six molybdenite samples from the Huangshaping deposit were selected for Re-Os isotope ... The large-scale Huangshaping Pb-Zn-W-Mo polymetallic deposit is located in the central Nanling min- eralization zone, South China. Six molybdenite samples from the Huangshaping deposit were selected for Re-Os isotope measurement in order to define the mineralization age of the deposit. It yields a Re-Os isochron age of 154.8±1.9 Ma (2σ ), which is in accordance with the Re-Os model ages of 150.9― 156.9 Ma. This age is about 7 Ma younger than their host granite porphyry, which was dated as 161.6±1.1 Ma by zircon U-Pb method using LA-ICPMS. All these ages demonstrate that the Huang- shaping granite and related Pb-Zn-W-Mo deposit occurred in the middle Yanshanian period, when many other granitoid and related ore deposits emplaced and formed, e.g. the Qitianling granite and Furong tin deposit, the Qianlishan granite and giant Shizhuyuan W-Sn-Mo-Bi deposit and Jinchuantang Sn-Bi deposit in the nearby area. They constitute the main part of the magmatic-metallogenic belt of southern Hunan, and represent the large-scale metallogeny in middle Yanshanian in the area. The lower rhenium content in molybdenite of Huangshaping deposit suggests that the ore-forming material was mainly of crust origin. 展开更多
关键词 RE-OS isotope DATING MOLYBDENITE Huangshaping deposit granite southern HUNAN Province
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Abundance and biomass of meiobenthos in the spawning ground of anchovy (Engraulis japanicus) in the southern Huanghai Sea 被引量:29
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作者 LIUXiaoshou ZHANGZhinan HUANGYong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第3期94-104,共11页
A grid of 22 stations, giving a broad coverage of the spawning ground of anchovy in the southern Huanghai Sea was selected. Undis- turbed sediments were taken from sampling stations during the cruise in June 2003. The... A grid of 22 stations, giving a broad coverage of the spawning ground of anchovy in the southern Huanghai Sea was selected. Undis- turbed sediments were taken from sampling stations during the cruise in June 2003. The average abundance of meiofauna is (1 584± 686) ind./10cm2, with corresponding biomass (dwt) of (1 086±425)!μg/10cm2. The pattern of abundance of meiofauna is similar to the pattern of biomass. There are 65.88% meiofauna in 0 ̄2 cm sediments, 27.66% in 2 ̄5 cm sediments and 6.47% in 5 ̄8 cm sediments. The Spearman correlation analysis between meiofauna and environmental factors shows that abundance of meiofauna, free living ma- rine nematodes, benthic copepods has significant positive correlations with Chl-a. And the abundance of copepods has significant posi- tive correlations with several factors such as Chl-a, Pha-a, Chl-a plus Pha-a and organic matter. A total of 18 meiofauna groups are i- dentified. Nematode is the most dominant group, average abundance (1 404±670) ind/10cm2, accounting for 88.65%, and the follow- ing groups are also important: benthic copepods (5.48%), kinorhyncha (1.26%), polychaeta (1.07%). By biomass, dominant groups are nematodes (51.72%), polychaeta (21.84%), copepods (14.87%), ostracoda (4.92%), kinorhyncha (3.67%). A total of 90 species of ne- matodes are identified. The species composition of nematodes is listed based on selected two stations 7794 (coastal area) and 10694 (cold water mass in deep waters). 展开更多
关键词 meiofauna free living marine nematodes benthic copepods ABUNDANCE BIOMASS southern Huanghai Sea
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华北克拉通东北缘岩石圈深部物质组成的不均一性:来自吉林南部中生代火山岩元素及Sr-Nd同位素地球化学的证据 被引量:28
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作者 裴福萍 许文良 +2 位作者 杨德彬 于洋 孟恩 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期1962-1974,共13页
本文报导了吉林南部果松组和三棵榆树组火山岩的全岩K-Ar和角闪石^(40)Ar/^(39)Ar定年结果和岩石地球化学资料,并讨论了吉林南部早白垩世火山岩岩浆源区性质以及空间变异。定年结果显示,果松组和三棵榆树纽火山岩的形成时代分别为130.2&... 本文报导了吉林南部果松组和三棵榆树组火山岩的全岩K-Ar和角闪石^(40)Ar/^(39)Ar定年结果和岩石地球化学资料,并讨论了吉林南部早白垩世火山岩岩浆源区性质以及空间变异。定年结果显示,果松组和三棵榆树纽火山岩的形成时代分别为130.2±0.3Ma和118.3±1.9Ma。果松组火山岩主要由玄武岩-玄武质粗面安山岩-粗面安山岩-英安岩组成;它们的SiO_2含量介于46%~64%,Mg~#介于31~50之间,Al_2O_3含量介于14.9%~18.9%之间,全碱含量(Na_2O+K_2O)介于4.61%~9.23%之间,属于亚碱性系列,具钙碱性演化趋势;并以富集大离子亲石元素(LILEs)和轻稀土元素(LREEs),亏损重稀土元素(HREEs)和Nb、Ta、Ti等高场强元素(HFSEs)为特征;(^(87)Sr/^(86)Sr)_i值和ε_(Nd)(t)值分别介于0.7065~0.7077和-2.67~ -19.71之间。果松组火山岩的成分具有较好的空间变异趋势,由东向西,火山岩的基性程度增高,东部果松组火山岩具有较高的(^(87)Sr/^(86)Sr)。值,而西部具有较低的ε_(Nd)(t)值。三棵榆树组火山岩由粗面安山岩和粗面英安岩组成;三棵榆树组火山岩的SiO_2含量介于55.5%~65.8%之间,Mg~#介于42~50,Al_2O_3含量介于15.0%~15.7%,全碱含量偏高(Na_2O+K_2O=6.93%~9.24%),主体属于亚碱性系列,具钙碱性系列的演化趋势;并以较高的Th/U(5.36~5.82)、Ba/Nh(50.2~120.0)、(La/Yh)_N(32.9~47.9)和Sr/Y(50.0~72.4)比值为特征;它们的(^(87)Sr/^(86)Sr)_i值和ε_(Nd)(t)值分别变化于0.7056~0.7057和-8.99~-19.71之间。上述特征揭示,果松组火山岩(130Ma)的形成主要与古太平洋板块的俯冲作用有关,岩浆来源于受流体/熔体交代的地幔楔,东西部受到不同程度陆壳物质的混染。与果松组火山岩相比,三棵榆树组火山岩(118Ma)形成于俯冲背景下的相对引张环境,岩浆来源于受交代的岩石圈地幔,但受到深部陆壳物质的混染。 展开更多
关键词 华北克拉通 东北缘 岩石圈 物质组成 不均一性 吉林 南部 中生代火山岩 元素 Sr-Nd同位素 岩石地球化学 证据 North China CRATON deep Late Mesozoic Jilin Province southern volcanic rocks rare earth elements spatial variation
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Evolution of Intraseasonal Oscillation over the Tropica lWestern Pacific/South China Sea and Its Effect to the Summer Precipitation in Southern China 被引量:27
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作者 李崇银 李桂龙 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1997年第2期123-131,共9页
In this paper, the evolution of intraseasonal oscillation over the South China Sea and tropical western Pacific area and its effect to the summer rainfall in the southern China are studied based on the ECMWF data and ... In this paper, the evolution of intraseasonal oscillation over the South China Sea and tropical western Pacific area and its effect to the summer rainfall in the southern China are studied based on the ECMWF data and TBB data) analyses. A very low-frequency waves exist in the tropics and play an important role in dominating intraseasonal oscillation and lead to special seasonal variation of intraseasonal oscillation over the South China Sea/tropical western Pacific area. The intraseasonal oscillation (convection) over the South China Sea and tropical western Pacific area is closely related to the summer rainfall (convection) in the southern China. Their relationship seems to be a seesaw feature, and this relationship resulting from the different pattern of convection in those two regions is caused by the differnt type of local meridional circulation. 展开更多
关键词 EVOLUTION Intraseasonal oscillation Precipitation in southern China Local meridional circulation
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The pathway of the interdecadal variability in the Pacific Ocean 被引量:24
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作者 WANG Dongxiao & LIU Zhengyu1. South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China 2. Department of Atmospheric & Oceanic Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA Correspondence should be addressed to Wang Dongxiao 《Chinese Science Bulletin》 SCIE EI CAS 2000年第17期1555-1561,共7页
Cases of the interdecadal variability in the Pacific Ocean and their evolution were examined in the paper with the statistic methods (CEOF and composite analysis) over the period of 1950-1993. Observations of oceanic ... Cases of the interdecadal variability in the Pacific Ocean and their evolution were examined in the paper with the statistic methods (CEOF and composite analysis) over the period of 1950-1993. Observations of oceanic temperatures in the upper 400 m revealed an obvious region of the interdecadal signals in the central North Pacific. Such signals propagated south westward, then subducted to the subtropics. The hypothesized link for interdecadal oceanic variability between the subtropics and the tropics, especially with the western tropical Pacific was unraveled in order to detect the cause of decadal signals in the tropics. The thermal anomalies subducted in the central North Pacific east to the dateline only reach 18°N. There has been no further southward propagation since then due to a certain barrier. The origin of the interdecadal signals in the western tropical Pacific was traced to the southern tropical Pacific. There is a meridional pathway around the dateline where the signals were loaded. 展开更多
关键词 INTERDECADAL OCEANIC variability southern TROPICAL PACIFIC signal pathway.
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An Important Spreading Event of the Neo-Tethys Ocean during the Late Jurassic and Early Cretaceous: Evidence from Zircon U-Pb SHRIMP Dating on Diabase in Nagarze, Southern Tibet 被引量:27
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作者 JIANG Sihong NIE Fengjun HU Peng LIU Yan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期522-527,共6页
Widely distributed in Gyangzê-Chigu area, southern Tibet, NW- and nearly E-W-trending diabase(gabbro)-gabbro diorite dykes are regarded as the product of the large-scale spreading of the late Neo-Tethys Ocean. ... Widely distributed in Gyangzê-Chigu area, southern Tibet, NW- and nearly E-W-trending diabase(gabbro)-gabbro diorite dykes are regarded as the product of the large-scale spreading of the late Neo-Tethys Ocean. In order to constrain the emplacement age of these dykes, zircons of two samples from diabases in Nagarzê were dated by using the U-Pb SHRIMP method. Two nearly the same weighted mean ^206pb/^23SU ages were obtained in this paper, which are 134.9±1.8 Ma (MSWD=0.65) and 135.5 ± 2.1 Ma (MSWD=1.40), respectively. They not only represent the crystallization age of the diabase, but also documented an important spreading event of the Neo-Tethys Ocean during the late Jurassic and early Cretaceous. This dating result is of great significance to reconstruct the temporal framework of the late Neo-Tethys Ocean in the Qinghai-Tibet Plateau. 展开更多
关键词 DIABASE zircon U-Pb SHRIMP dating spreading event NEO-TETHYS Nagarzê southern Tibet
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Molecular Characterization of Segments S7 to S10 of a Southern Rice Black-streaked Dwarf Virus Isolate from Maize in Northern China 被引量:28
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作者 Xiao Yin Fei-fei Xu +3 位作者 Fang-qiang Zheng Xiang-dong LI Bao-shen Liu Chun-qing Zhang 《Virologica Sinica》 SCIE CAS CSCD 2011年第1期47-53,共7页
Southern rice black-streaked dwarf virus (SRBSDV) is a novel Fijivirus prevalent in rice in southern and central China,and northern Vietnam. Its genome has 10 segments of double-stranded RNA named S1 to S10 according ... Southern rice black-streaked dwarf virus (SRBSDV) is a novel Fijivirus prevalent in rice in southern and central China,and northern Vietnam. Its genome has 10 segments of double-stranded RNA named S1 to S10 according to their size. An isolate of SRBSDV,JNi4,was obtained from naturally infected maize plants from Ji'ning,Shandong province,in the 2008 maize season. Segments S7 to S10 of JNi4 share nucleotide identities of 72.6%-73.1%,72.3%-73%,73.9%-74.5% and 77.3%-79%,respectively,with corresponding segments of Rice black-streaked dwarf virus isolates,and identities of 99.7%,99.1%-99.7%,98.9%-99.5%,and 98.6%-99.2% with those of SRBSDV isolates HN and GD. JNi4 forms a separate branch with GD and HN in the phylogenetic trees constructed with genomic sequences of S7 to S10. These results confirm the proposed taxonomic status of SRBSDV as a distinct species of the genus Fijivirus and indicate that JNi4 is an isolate of SRBSDV. Shandong is so far the northernmost region where SRBSDV is found in China. 展开更多
关键词 southern rice black-streaked dwarf virus (SRBSDV) Maize rough dwarf disease (MRD) Identity Phylogenetic analysis
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