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Recently Discovered Basilosaurid, Baluchithere Rhinoceros, Horses, Sea Cow, Proboscidean, Eucrocodile, Pterosaurs, Plesiosaur, Fishes, Invertebrates and Wood Fossils, Tracks and Trackways of Dinosaurs from Pakistan;Comparison of Recognized Four Titanosaur Taxa of Indo-Pakistan with Madagascar 预览
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作者 Muhammad Sadiq Malkani 《地质学期刊(英文)》 2019年第12期919-955,共37页
Recent Geological and Paleontological exploration during the start of new/third millennium (from 2000 to 2019) yielded 45 taxa of vertebrates and invertebrates from Mesozoic and Tertiary (except a jawless fish from Ca... Recent Geological and Paleontological exploration during the start of new/third millennium (from 2000 to 2019) yielded 45 taxa of vertebrates and invertebrates from Mesozoic and Tertiary (except a jawless fish from Cambrian and a trilobite from Permo-Triassic boundary) strata of Pakistan like dinosaurs, mesoeucrocodiles, eucrocodiles, pterosaurs-light bodied flying reptiles, plesiosaurs-broad bodied and ichthyosaurs-streamlined bodied reptiles and fishes, basilosaurid whale, Baluchithere rhinoceroses and paleo-horses mammals, invertebrates (hippurites/rudists, oysters, mussels and other bivalves, ammonites, belemnites nautilides and gastropods Mollusca, starfish echinoids, nummulites, assilina and alveolina foraminifers, arthropods and corals), algae, sponge and wood fossils. Here described new fossil records would attract widespread interests. 展开更多
关键词 Recent Geological and Paleontological Exploration BIOTA Pakistan
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古近纪/新近纪之交青藏高原陆地生态系统的重大转折
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作者 邓涛 吴飞翔 +2 位作者 王世骐 苏涛 周浙昆 《科学通报》 EI CAS CSCD 北大核心 2019年第27期2894-2906,共13页
新生代古近纪/新近纪之交是地球生命环境演化史上的重要节点,生物界总体面貌更趋近现代.青藏高原的隆升对该地区的陆地生态系统产生了重大影响,最终形成现代高原冰冻圈环境与生态体系.通过研究近年来高原腹地伦坡拉、尼玛盆地古近纪-新... 新生代古近纪/新近纪之交是地球生命环境演化史上的重要节点,生物界总体面貌更趋近现代.青藏高原的隆升对该地区的陆地生态系统产生了重大影响,最终形成现代高原冰冻圈环境与生态体系.通过研究近年来高原腹地伦坡拉、尼玛盆地古近纪-新近纪沉积中产出的大量动植物化石,发现青藏高原生态系统在古近纪/新近纪之交经历了由热带、亚热带生态体系向高原型生物群落的重大转折.以上地点渐新世地层中的鱼类、植物和昆虫化石证据表明,高原腹地在26~24 Ma仍为温暖湿润的低地,来自印度洋的暖湿气流还可深入藏北.这一时期动植物以攀鲈和棕榈为代表,不仅反映热带、亚热带气候特征,并且表明当时盆地可能的最大海拔仅有2300 m左右.自中新世开始,高原陆地生态系统整体上向现代型过渡.裂腹鱼开始出现,并自此向特化等级演化,至上新世出现高度特化种类.早中新世植被以北温带落叶阔叶树种占优势,同时出现大量针叶树,草本植物进一步发展,反映气候已具温带特征.哺乳动物在早中新世出现适应温带森林的近无角犀等,而以披毛犀为代表的寒冷适应性冰期动物祖先出现于上新世.青藏高原生态系统这一重大转折与高原主体在早中新世隆升到接近3000 m高度所产生的降温效应相关,同时也受到全球气候转凉的影响. 展开更多
关键词 新生代 青藏高原 生物群 陆地生态系统 构造隆升 气候变化
Jurassic integrative stratigraphy and timescale of China
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作者 Diying HUANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第1期223-255,共33页
The Jurassic stratigraphy in China is dominated by continental sediments. Marine facies and marine-terrigenous facies sediment have developed locally in the Qinghai-Tibet area, southern South China, and northeast Chin... The Jurassic stratigraphy in China is dominated by continental sediments. Marine facies and marine-terrigenous facies sediment have developed locally in the Qinghai-Tibet area, southern South China, and northeast China. The division of terrestrial Jurassic strata has been argued, and the conclusions of biostratigraphy and isotope chronology have been inconsistent.During the Jurassic period, the North China Plate, South China Plate, and Tarim Plate were spliced and formed the prototype of ancient China. The Yanshan Movement has had a profound influence on the eastern and northern regions of China and has formed an important regional unconformity. The Triassic-Jurassic boundary(201.3 Ma) is located roughly between the Haojiagou Formation and the Badaowan Formation in the Junggar Basin, and between the Xujiahe Formation and the Ziliujing Formation in the Sichuan Basin. The early Early Jurassic sediments generally were lacking in the eastern and central regions north of the ancient Dabie Mountains, suggesting that a clear uplift occurred in the eastern part of China during the Late Triassic period when it formed vast mountains and plateaus. A series of molasse-volcanic rock-coal strata developed in the northern margin of North China Craton in the Early Jurassic and are found in the Xingshikou Formation, Nandailing Formation, and Yaopo Formation in the West Beijing Basin. The geological age and markers of the boundary between the Yongfeng Stage and Liuhuanggou Stage are unclear. About 170 Ma ago, the Yanshan Movement began to affect China. The structural system of China changed from the near east-west Tethys or the Ancient Asia Ocean tectonic domain to the north-north-east Pacific tectonic domain since 170–135 Ma. A set of syngenetic conglomerate at the bottom of the Haifanggou or Longmen Fms. represented another set of molasse-volcanic rock-coal strata formed in the Yanliao region during the Middle Jurassic Yanshan Movement(Curtain A1). The bottom of the conglomerate is approximately equivalent to the boundary of t 展开更多
关键词 Continental JURASSIC BIOSTRATIGRAPHY Isotope CHRONOLOGY Age frame Yanshan Movement Yanliao BIOTA
First report on Guanshan Biota(Cambrian Stage 4)at the stratotype area of Wulongqing Formation in Malong County,Eastern Yunnan,China 预览
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作者 Feiyang Chen Zhifei Zhang +2 位作者 Marissa J. Betts Zhiliang Zhang Fan Liu 《地学前缘:英文版》 CAS CSCD 2019年第4期1459-1476,共18页
Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological exp... Exceptionally preserved fossils,such as those from Cambrian Burgess Shale-type fossil-Lagerstatten are critical because of their unique contributions to knowledge of the phylogenetic radiation and palaeoecological expansion of metazoans during the Cambrian explosion.Critically,these deposits provide information that is usually unobtainable from shelly and skeletonized fossils alone.The Guanshan Biota(Cambrian Series 2,Stage 4)in the Yunnan Province of South China,has produced abundant and diverse,exquisitely preserved fossils that often retain soft tissues and organs.To date,most fossils from the Guanshan Biota have been collected from localities such as Gaoloufang and Gangtoucun,which have become inaccessible due to new urban expansions and constructions of residential buildings.Here we present the first report of soft bodied fossils from a new section at Kanfuqing,close to the Wulongqing village in Malong County,approximately 3 km east of the Wulongqing Formation stratotype section.Fossils retain soft morphology,and include brachiopods with delicate marginal setae,priapulids with well-preserved sclerites and vetulicolians with entire sections of body.In addition,this fauna includes rare occurrences of trilobites preserved with soft tissues replicated as pyrite pseudomorphs after weathering.This discovery represents an important palaeogeographical extension of soft-bodied fossils of the Guanshan fauna to the east of the Xiaojiang Fault(related to Tsinning tectonic movements ca.700 Ma).The fauna from the new Kanfuqing section is similar to that reported from the Wulongqing Formation west of the Xiaojiang Fault,and thus has significant implications for early Cambrian palaeogeography,faunal successions and palaeoenvironments of eastern Yunnan. 展开更多
关键词 Guanshan BIOTA Early CAMBRIAN Xiaojiang Fault EASTERN YUNNAN PALAEOENVIRONMENT PALAEOGEOGRAPHY
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珠江口生物中多氯萘、六氯丁二烯和五氯苯酚的含量水平和分布特征 被引量:1
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作者 黄玉妹 陈来国 +3 位作者 任璐 冯倩华 卢清 刘明 《环境化学》 CSCD 北大核心 2018年第8期1755-1762,共8页
为了解珠江口生物中新增持久性有机污染物多氯萘(PCNs)、六氯丁二烯(HCBD)和五氯苯酚(PCP)及其醚类(五氯苯甲醚,PCA)和酯类(月桂酸五氯苯酯,PCPL)的污染特征,本研究采集了珠江口鱼类、甲壳类(虾和蟹)和贝类(牡蛎)等生物样... 为了解珠江口生物中新增持久性有机污染物多氯萘(PCNs)、六氯丁二烯(HCBD)和五氯苯酚(PCP)及其醚类(五氯苯甲醚,PCA)和酯类(月桂酸五氯苯酯,PCPL)的污染特征,本研究采集了珠江口鱼类、甲壳类(虾和蟹)和贝类(牡蛎)等生物样品,并分析了这些样品中PCNs、HCBD、PCP、PCA和PCPL的含量.珠江口牡蛎样品中PCNs的浓度(32—77 ng·g^(-1)脂重(lw))显著高于鱼类样品(3.0—27 ng·g^(-1)lw)和甲壳类的虾蟹样品(2.7—29 ng·g^(-1)lw)(P〈0.01).低氯代的PCN2—PCN28是珠江口生物样品中PCNs的主要成分,其贡献率为76%—99%.牡蛎样品中PCNs的毒性当量为0.03—4.4 pg·g^(-1)lw,平均值为1.8±1.4 pg·g^(-1)lw,高于鱼类和虾蟹样品;PCN73是珠江口生物样品毒性当量的主要贡献者(60.8%—99.8%).珠江口生物样品中HCBD的浓度为n.d.—0.99 ng·g^(-1)lw,不同生物样品中HCBD的浓度没有显著性差异(P〉0.05).PCA在生物样品中检出率高于PCP和PCPL.与其他研究相比,珠江口生物样品中PCP的浓度(n.d.—100 ng·g^(-1)lw)处于中等偏低水平. 展开更多
关键词 多氯萘 六氯丁二烯 五氯苯酚 持久性有机污染物 生物 珠江口
不同生物群解脲支原体感染导致输卵管性不孕的相关性研究 预览
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作者 何静 刘彩红 +2 位作者 张宝慧 高彩凤 纪妍 《齐齐哈尔医学院学报》 2018年第7期782-784,共3页
目的探讨不同生物群解脲支原体(UU)与输卵管性不孕(TFI)的相关性。方法选取496例TFI患者和426例正常受孕受试者,取其泌尿生殖道分泌物,采用培养法鉴别UU阳性感染,实时荧光定量PCR分析UU生物群。结果 TFI组UU阳性检出率为60.69%(301... 目的探讨不同生物群解脲支原体(UU)与输卵管性不孕(TFI)的相关性。方法选取496例TFI患者和426例正常受孕受试者,取其泌尿生殖道分泌物,采用培养法鉴别UU阳性感染,实时荧光定量PCR分析UU生物群。结果 TFI组UU阳性检出率为60.69%(301/496),正常受孕组UU阳性检出率为34.5%(147/426),TFI组显著高于正常受孕组,差异有统计学意义(χ2=62.871,P〈0.05);TFI组中Upa阳性检出率为18.35%(91/496),正常受孕组Upa阳性检出率为16.43%(70/426),两组比较差异无统计学意义(χ~2=0.583,P〉0.05);TFI组中Uur阳性检出率为27.22%(135/496),正常受孕组Uur阳性检出率为9.86%(42/426),TFI组显著高于正常受孕组,差异有统计学意义(χ~2=44.517,P〈0.05);TFI组中Uur+Upa混合感染阳性检出率为15.12%(75/496),正常受孕组Uur+Upa混合感染阳性检出率为8.22%(35/426),TFI组显著高于正常受孕组,差异有统计学意义(χ~2=19.054,P〈0.05)。结论 Upa生物群和TFI的相关性并不明显,Uur生物群可能是导致TFI的主要生物群。 展开更多
关键词 解脲支原体 输卵管性不孕 生物群
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超高效液相色谱-串联质谱多目标分析生物样品中的微量内分泌干扰污染物 预览 被引量:1
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作者 刘珺 唐才明 +3 位作者 熊松松 凡玉娟 郑可 彭先芝 《分析化学》 SCIE EI CAS CSCD 北大核心 2017年第3期434-440,共7页
建立了生物样品中9种微量内分泌干扰物(EDCs)的多目标分析方法。采用旋涡振荡-超声波辅助萃取,结合凝胶渗透色谱(GPC)除去大分子有机物干扰,再经硅胶柱层析进一步净化,最后应用超高效液相色谱-串联质谱(UHPLC-MS/MS)检测。GPC采... 建立了生物样品中9种微量内分泌干扰物(EDCs)的多目标分析方法。采用旋涡振荡-超声波辅助萃取,结合凝胶渗透色谱(GPC)除去大分子有机物干扰,再经硅胶柱层析进一步净化,最后应用超高效液相色谱-串联质谱(UHPLC-MS/MS)检测。GPC采用乙酸乙酯-环己烷混合溶液(1:1,V/V)为流动相,选择12-28 mL为目标化合物馏分的收集段;质谱采用电喷雾离子源正离子模式和大气压化学电离源负离子模式,数据采集为多重反应监测模式。方法回收率为65.2%-118.0%,定量限为0.1-9.7 ng/g dw(干重)。采用本方法初步分析了珠江水系鲤鱼脊肉中的内分泌干扰污染物,结果表明,除均二苯脲和三氯卡班未被检出外,其它内分泌干扰污染物的含量为0.1-22.6 ng/g dw。 展开更多
关键词 内分泌干扰物 超高效液相色谱-串联质谱 生物样品
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Biogeology. Biosphere from the Archean to Technogene 预览
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作者 Rudko G. 《地质资源与工程:英文版》 2016年第1期12-28,共17页
关键词 地质资源 地质工程 地质学 内力作用 外力作用
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Estimation of Annual Effective Dose Due to Ingestion of Natural Radionuclides in Cattle in Tin Mining Areas of Jos Plateau, Nigeria: Are Large Mammals Really Affected? 预览
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作者 A. S. Aliyu T. A. Mousseau +2 位作者 N. N. Garba H. T. Abba A. T. Ramli 《自然科学期刊(英文)》 2015年第4期190-196,共7页
We have read with great interest the paper which was published in Natural Science, 2014 issue number 6 titled “Estimation of annual effective dose due to ingestion of natural radionuclides in cattle in tin mining are... We have read with great interest the paper which was published in Natural Science, 2014 issue number 6 titled “Estimation of annual effective dose due to ingestion of natural radionuclides in cattle in tin mining area of Jos Plateau, Nigeria” [1]. The paper motivated us to use state-of-the-art computational technique to investigate the risks of the tin mining activity in Jos-Plateau, Nigeria on large mammals (e.g. cattle). The Tier 2 Erica Tool assessment was used to estimate the total dose rate and risk quotients of these reference terrestrial animals. Our investigation revealed that the expected and conservative risk quotients of large mammals due to internal and external exposure to enhanced level of radioactivity are 0.05 and 0.16, respectively. Since the risk quotients are less than unity, this indicates that there is less than 5% probability that the screen dose rate (10 μGy&bull;h–1) is exceeded. The estimated total dose rate to large mammals is 0.52 μGy&bull;h–1 which is not statistically significant. A critical analysis of [1] is presented in the introductory part of this paper. 展开更多
关键词 TIN Mining RADIOECOLOGY BIOTA Jos Dose Rate
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Concerning the Original Viewpoint of Biogeologic Accumulation of the Old Bedded Phosphorites in the Khubsugul and Zavkhan Basins of Mongolia 预览
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作者 Dorj Dorjnamjaa Gundsambuu Altanshagai 《地质学期刊(英文)》 2015年第9期666-675,共10页
This paper concerns deals with?biogeologic?accumulation and their peculiarities, lithological unites of the phosphorite-bearing formations of these basins and an evolution of the old biota. Old bedded phosphorites are... This paper concerns deals with?biogeologic?accumulation and their peculiarities, lithological unites of the phosphorite-bearing formations of these basins and an evolution of the old biota. Old bedded phosphorites are believed to be connected with specific biogeological events happening in the Neoproterozoic glaciation, which was followed by rapid deglaciation,?Ediacaran bioradiation and the “great” postglacial transgression bearing phosphorites at its initial phase. The Mongolian phosphate basins give evidence of this phenomenon. Khubsugul basin is located in the northern Mongolia. The Neoproterozoic-Cambrian phosphorite-bearing khubsugul group is subdivided into 3 formations as ongolik, kheseen and erkhelnuur which are rich in organic fossils (a group of cyanobacterial mats, archaeocyaths, trilobites) in the ascending order. The Zavkhan basin lies in the western Mongolia. The Ediacaran-lower Cambrian sediments are divided into five formations: Maikhanuul (diamictites), Tsagaanolom (phosphorite-bearing carbonate), Bayangol, Salaanygol and Khairkhan. All the formations contain the paleontological fossils (algae, sponges, cyanobacterial mats, ichnocoenosis, soft-bodied fauna, archaeocyaths, etc.). Bedded phosphorites are the object for comprehensive research of bacterial paleontology. It is shown at example of the Mongolian Khubsugul and Zavkhan sea shelf phosphate basins. The expounded actual material clearly shows that the heterogeneous biologic activity, suitable geologic (transgressive systems tracts) and paleogeographic (glaciations, warm climate, etc.) conditions played an important role in the formation and accumulation of the biogenic bedded phosphorites. 展开更多
关键词 Khubsugul Zavkhan Basin PHOSPHORITE FOSSILS BIOTA ACCUMULATION
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有机磷酸酯类阻燃剂在环境中的最新残留现状研究 预览 被引量:3
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作者 隋强男 翟玮 耿存珍 《环境科学与管理》 CAS 2015年第10期31-34,共4页
随着卤系阻燃剂的逐步被禁用,有机磷酸酯类(OPEs)阻燃剂的使用量剧增,在环境中的残留量也随之增加。而环境残留的大部分OPEs对生态系统和人类健康表现出一定的毒理学作用,因此,调查OPEs类阻燃剂在环境中的最新残留是很有必要的。文章主... 随着卤系阻燃剂的逐步被禁用,有机磷酸酯类(OPEs)阻燃剂的使用量剧增,在环境中的残留量也随之增加。而环境残留的大部分OPEs对生态系统和人类健康表现出一定的毒理学作用,因此,调查OPEs类阻燃剂在环境中的最新残留是很有必要的。文章主要从大气环境、水环境、土壤环境和生物介质几个方面对有机磷酸酯的环境残留进行了详细的调查,并提出了研究的方向和建议。 展开更多
关键词 有机磷酸酯 大气 水体 土壤 生物体 残留量
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影响银淡水生物水质基准的环境因素分析 预览 被引量:4
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作者 马燕 吴丰昌 +4 位作者 谭伟强 冯承莲 张瑞卿 王颖 白英臣 《生态毒理学报》 CAS CSCD 北大核心 2015年第1期235-244,共10页
水质基准是制定水环境质量标准,以及评价、预测和控制与治理水体污染的重要依据.为了系统分析水体硬度、物种门类和地域条件对水质基准的影响,本研究筛选了6门20科25种水生生物的毒性数据,用毒性百分数排序法推导了中国银的淡水生物水... 水质基准是制定水环境质量标准,以及评价、预测和控制与治理水体污染的重要依据.为了系统分析水体硬度、物种门类和地域条件对水质基准的影响,本研究筛选了6门20科25种水生生物的毒性数据,用毒性百分数排序法推导了中国银的淡水生物水质基准.研究结果表明,银的基准最大浓度(CMC)与水体硬度呈幂函数关系,等式为CMC=0.85&#215;e[0.62ln(水体硬度)-4.28]μg·L-1,基准连续浓度为0.02 μg·L-1.中国和美国2个不同生物区系研究都表明低等生物(无脊椎动物)比高等生物(脊椎动物)对银离子的毒性更为敏感.由地域条件引起的生物区系和敏感物种差异及基准推导方法的不同也会影响水质基准值. 展开更多
关键词 淡水生物 水质基准 硬度校正 物种门类 生物区系 毒性百分数排序法
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核电厂生物辐射影响评价参数研究 预览
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作者 杜红燕 魏其铭 +1 位作者 白晓平 王晓亮 《南方能源建设》 2015年第4期151-154,101共5页
对ERICA程序及其计算参数进行了简要介绍,推荐了水生生态系统和陆生生态系统的不同生态系统类型以及滨海厂址和内陆厂址的不同厂址类型中计算参数的选取方法,研究成果对后续核电厂的生物辐射影响评价工作具有借鉴意义。
关键词 核电厂 ERICA程序 生物 辐射影响评价 参数 分配系数 浓集因子 剂量率转换因子
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太湖梅梁湾沉积物和水生生物中有机氯农药分布特征及风险评估 预览 被引量:7
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作者 许妍 周亚子 +3 位作者 陈曦 缪蜀江 林汉华 秦庆东 《东南大学学报:自然科学版》 EI CAS CSCD 北大核心 2015年第2期328-335,共8页
根据太湖梅梁湾有机氯农药(OCPs)污染情况,采用GC/ECD分析了梅梁湾沉积物,并对4种鱼及螺狮为代表的水生生物中有机氯农药的残留现状进行了风险评估.结果表明:沉积物(干重)中OCPs浓度范围在8.45-48.54 ng/g之间,生物样品(湿重)中... 根据太湖梅梁湾有机氯农药(OCPs)污染情况,采用GC/ECD分析了梅梁湾沉积物,并对4种鱼及螺狮为代表的水生生物中有机氯农药的残留现状进行了风险评估.结果表明:沉积物(干重)中OCPs浓度范围在8.45-48.54 ng/g之间,生物样品(湿重)中的浓度范围在2.68-31.34 ng/g之间.人类食用OCPs污染的水产品的潜在健康风险评估显示,从非致癌风险角度滴滴涕(DDTs)、六氯苯(HCB)、氯丹(CHL)和七氯环氧的危险商RHQ均小于1;从致癌风险角度,除CHL外,DDTs、HCB、六六六(HCHs)、七氯环氧的危险比RHR均大于1,长期癌症风险不容忽视.根据淡水沉积物质量导则标准估算,太湖梅梁湾沉积物中OCPs残留对水生生态系统的影响较小. 展开更多
关键词 有机氯农药 沉积物 水生生物 风险评估
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International Recommendations on Calculation of Absorbed Dose in Biota: A Comprehensive Revue 预览
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作者 Wagner de S. Pereira Alphonse Kelecom 《环境保护(英文)》 2014年第9期751-759,共9页
Since the early times, radioprotection has been focused on the human being. Currently this approach has changed, being now also necessary to take care of the protection of the environment from unwanted effects of ioni... Since the early times, radioprotection has been focused on the human being. Currently this approach has changed, being now also necessary to take care of the protection of the environment from unwanted effects of ionizing radiation. To this end, several institutions (UNSCEAR, ICRP, IAEA, DOE, ACRP) and consortia of institutions (FASSET, ERICA) have established procedures in order to protect the biota of such effects. Developed procedures are based on the calculation of the absorbed dose in biota (ICRP, DOE, IAEA), or on environmental risk assessment―ERA (DOE, ACRP, FASSET, ERICA);but even in this latter approach the parameters used are related to the absorbed doses in biota. The calculation of dose is the standard procedure in human radioprotection, and this points such an approach as the most interesting for providing a convergence between human and nonhuman (= biota) radioprotections. On the other hand, the ERA approach is easier to apply, because this methodology is used in several countries for non-radioactive contamination assessments. Since the world radioprotection system follows a number of institutions (UNSCEAR, ICRP, IAEA and regulatory institutions of member countries) that use dose calculation, this appears to be the way for biota radioprotection. We here review and comment the evolution of the concepts and approaches of the recommendations for radioprotection of non-human biota. 展开更多
关键词 BIOTA Absorbed DOSE RADIOPROTECTION INTERNATIONAL RECOMMENDATIONS
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Middle Devonian-Tournaisian rocks and biota on Hainan Island, South China
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作者 ZHANG RenJie YAO HuaZhou +1 位作者 WANG JianXiong TU Bing 《中国科学:地球科学英文版》 SCIE EI CAS 2013年第11期1934-1941,共8页
On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first time.The Devonian rocks include the Middle Devonian ... On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first time.The Devonian rocks include the Middle Devonian Jinbo Formation and the Upper Devonian Changjiang Formation,which are distributed in northwestern Hainan Island.The Jinbo Formation is represented by631 m of littoral facies deposits,and was intruded by the Yanshanian granite in the base.The presence of chitinozoans Eisenackitina caster,Funsochitina pilosa,and Lagenochitina amottensis indicates the Givetian in age.The Changjiang Formation is made up of 140 m of neritic facies rocks,and contains the Famennian conodonts Palmatolepis gracilis sigmoidalis,Polygnathus germanus,and corals Cystophrentis kalaohoensis.The Devonian-Tournaisian transition beds,the lower part of the Jishi Formation,are composed of 61–129 m sandstone and siltstone,with gastropods Euomphalus spp.and brachiopods,and marked by conglomerate with the underlying Devonian rocks.The middle-upper part of the Tournaisian Jishi Formation consists of 100–251 m clastic and carbonate rocks,containing abundant corals Pseudoularinia irregularis,conodonts Siphonodella isosticha,trilobites Weberiphillipsia linguiformis,and brachiopods.On the basis of the occurrence of Xinanosprifer flabellum and Homotoma sp.,the Nanhao Formation in southern Hainan Island is now regarded as the Lower Silurian,instead of the previously designated Lower Carboniferous.It is confirmed that no Carboniferous rocks occurred in the area south to the Gancheng-Wanning Fault. 展开更多
关键词 中泥盆世 岩石包 海南岛 中国南方 生物群 燕山期花岗岩 滨海相沉积 古生物学
电离辐射影响评价中的生物剂量率限值 预览 被引量:1
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作者 韩宝华 《辐射防护通讯》 2013年第5期1-5,40共6页
比较分析了近年来国际上主要研究机构/组织在生物剂量评估工作中剂量率限值的研究成果。欧洲ERICA项目和PROTECT项目使用FREDERICA效应数据库中的辐射效应数据估计单个生物物种的关键毒理数据EDR10,使用不同物种的EDR10与剂量率数据... 比较分析了近年来国际上主要研究机构/组织在生物剂量评估工作中剂量率限值的研究成果。欧洲ERICA项目和PROTECT项目使用FREDERICA效应数据库中的辐射效应数据估计单个生物物种的关键毒理数据EDR10,使用不同物种的EDR10与剂量率数据,建立物种敏感分布(SSD)曲线,采取物种敏感分布法推算出生物的筛选剂量率。在此基础上,结合我国放射生态学研究现状,提出了我国生物剂量率限值研究的相关建议。 展开更多
关键词 生物 剂量 筛选剂量率
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华北晚侏罗世-早白垩世风成砂沉积及其古地理和古生态学意义 预览 被引量:10
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作者 许欢 柳永清 +7 位作者 旷红伟 刘燕学 彭楠 董超 薛沛霖 徐加林 陈军 刘海 《古地理学报》 CAS CSCD 北大核心 2013年第1期11-30,共20页
华北晚侏罗世一早白垩世风成砂主要分布于鲁西蒙阴盆地上侏罗统三台组、辽西金一羊盆地上侏罗统一下白垩统土城子组、冀西北尚义盆地上侏罗统一下白垩统土城子组/后城组(原阎家窑组)、鄂尔多斯盆地下自垩统志丹群和甘肃下白垩统河口... 华北晚侏罗世一早白垩世风成砂主要分布于鲁西蒙阴盆地上侏罗统三台组、辽西金一羊盆地上侏罗统一下白垩统土城子组、冀西北尚义盆地上侏罗统一下白垩统土城子组/后城组(原阎家窑组)、鄂尔多斯盆地下自垩统志丹群和甘肃下白垩统河口群。各地风成砂岩均具高角度大型一巨型板状、楔状交错层理及平行层理,分选较好一好,磨圆次棱角状一次圆状等沉积特征。对华北晚侏罗世一早白垩世风成砂赋存层位以及风成砂岩形成时代进行了对比,将风成砂主要划分为3个时期,即基末利期一贝利阿斯期、凡兰吟期一欧特里夫期和欧特里夫期一阿普特期,且从鲁西到甘肃风成砂岩形成时代逐渐变新。通过上述5个地区风成砂的古风向研究发现,当时西北风盛行,古地磁研究显示风成砂岩发育于N25°-N45°之间区域。根据当前全球风带分布特征,认为华北晚侏罗世一早白垩世处于西风带上,为行星风系所控制。通过对比南半球同期风成砂岩古风向研究,提出全球南北半球中纬度地区均处于西风带上。结合风成砂及相应层位沉积特征、沉积环境的研究,初步推测晚侏罗世一早白垩世,华北N30°以北地区为干旱寒冷气候,而N30°以南地区则干旱炎热,华北北部整体处于海拔较高的山地环境,山间盆地发育,火山活动频发。燕辽生物群与热河生物群的演替过程与风成砂沉积相耦合,体现了古地理、古环境对生物群发展的制约作用。 展开更多
关键词 华北 晚侏罗世-早白垩世 风成砂岩 古风带 古地理 古生态 生物群
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辽宁太子河河岸带草本植物特征研究 预览 被引量:6
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作者 潘雪莲 张远 +2 位作者 孙建新 夏会娟 孔维静 《生态科学》 CSCD 北大核心 2013年第5期616-623,647共9页
应用样方法研究了辽宁太子河河岸带草本物种组成特征。结果表明:1)太子河河岸带共有草本植物207种,隶属于36科125属。其中菊科物种最多,水蓼出现的频率最高;2)太子河河岸带草本植物属级区系组成丰富,以温带分布区类型为主,其次... 应用样方法研究了辽宁太子河河岸带草本物种组成特征。结果表明:1)太子河河岸带共有草本植物207种,隶属于36科125属。其中菊科物种最多,水蓼出现的频率最高;2)太子河河岸带草本植物属级区系组成丰富,以温带分布区类型为主,其次为热带分布区类型;3)所有物种中,水生或湿生植物120种,旱生或中生植物87种,分别占总物种数的58.O%和42.0%;4)根据物种在样方中出现与否,将样点分为2类;一类分布于高海拔地区,物种以旱生或中生植物为主,物种数多,而另一类分布于低海拔地区,物种以水生或湿生植物为主,物种数较少;5)河岸带草本物种中有杂草和人类伴生种出现,且频率较高,表明太子河河岸带受到人类活动,如农田开发、挖沙和人类居住的影响。 展开更多
关键词 河岸带 区系 频度 水分生态型 人类干扰
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Water quality criteria research and progress 被引量:11
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作者 FENG ChengLian WU FengChang ZHAO XiaoLi LI HuiXian CHANG Hong 《中国科学:地球科学英文版》 SCIE EI CAS 2012年第6期 882-891,共10页
水质量标准(WQC ) 在周围的水环境是为污染物质或另外的危险因素的阀值限制,它基于科学实验和推测。直到现在,有关于在中国的水质量标准的学习可得到的有限信息。发射集中于中国的地区性的特征并且为水质量标准和环境管理的制订或修... 水质量标准(WQC ) 在周围的水环境是为污染物质或另外的危险因素的阀值限制,它基于科学实验和推测。直到现在,有关于在中国的水质量标准的学习可得到的有限信息。发射集中于中国的地区性的特征并且为水质量标准和环境管理的制订或修订提供科学支持的公民级的系统的 WQC 研究是必要的。这篇文章考察 WQC 的概念并且讨论方法论和 WQC 研究的全球进步。文章也在 WQC 研究总结关键科学问题,包括种类敏感分发,毒物学的端点选择,和模型选择。而且,我们能采用在 USA 使用的推导方法并且把 WQC 划分成尖锐、长期的标准。最后,在中国考虑 WQC 研究的当前的地位,我们为未来公民研究指出重要方向,包括本国的种类的选择和模型的全面使用。 展开更多
关键词 水质量标准 环境质量标准 科学实验 水质标准 危害因素 区域特点 环境管理 科学问题
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