《世界地震工程》被引特征的统计分析

以清华同方全文数据库为信息载体,统计分析了1999～2004年《世界地震工程》被我同期刊、学位论文与会议论文的引用状况。结果表明,该刊共被引981次,在同类期刊中被引次数名列前茅;引用期刊主要足近200种高等学校学报;引用期刊论文主要归类于建筑科学和地震学;引用学位论文的作者单位都是具有招收博士、硕士研究生的高等学校和科学研究机构;《世界地震工程》作为建筑科学类核心期刊有较高的学术影响力和较强的理论性与实用性。     

大数据环境下地震观测数据存储方案研究

大数据技术为处理海量地震观测数据提供了一种新的数据存储与计算模式。为了解决现有基于关系数据库存储方案的读写速度低、用户并发度低和可扩展性差等问题,以地震前兆观测数据为例,在详细分析业务需求的基础上,提出了基于HBase和Open TSDB的地震大数据存储方案,搭建了大数据测试平台,完成了不同存储方案下查询、插入性能实验和并发性实验。实验结果表明,与关系数据库存储方案相比,基于HBase和Open TSDB的存储方案具有很好的可扩展性和并发性,经过优化后的HBase存储方案具有更高的读取和存储性能。     

中国冰雪旅游研究：内涵辨析、脉络梳理与体系构建

推动冰雪旅游高质量发展践行了“冰天雪地也是金山银山”发展理念,助推着体育强国、健康中国建设,满足了人民日益增长的美好生活需要。中国冰雪旅游历经三十多年的发展,已形成规模化、整体化发展格局;北京冬奥会的筹办更是给冰雪旅游带来重大发展契机,利好政策陆续出台,消费热情不断高涨。与此同时,冰雪旅游相关研究也持续涌现,取得了丰厚研究成果。文章以“内涵辨析-脉络梳理-体系构建”为逻辑主线,从冰雪旅游基础概念、发展脉络演进、研究内容、研究方法及区域等方面对中国冰雪旅游展开分析和评述。研究表明：冰雪旅游内涵丰富,学者们从资源、动机以及季候等视角展开了概念界定;冰雪旅游研究历经4个阶段,研究与实践联系日益紧密,产业发展受资源、政策、市场等因素驱动;研究内容已形成一定体系,与国家、产业发展战略的结合有待加强;以定性研究为主,缺乏定量、纵深研究;研究区域高度集中在东北、华北地区,且视角较为宏观。最后提出从理论构建及研究视角、研究内容、研究方法、区域等方面进行未来研究的创新。以期推动中国冰雪旅游研究的理论化和体系构建,引领和指导未来冰雪旅游领域研究,推进中国后冬奥时代冰雪旅游高质量发展。     

莱州湾沉积物粒度与重金属分布特征

作者依据2019年8月份莱州湾海洋沉积物调查资料,分析了该海域表层沉积物粒径组成、重金属时空分布特征并评价了其生态风险。结果显示,莱州湾沉积物分为砂质粉砂、粉砂、粉砂质砂和砂4种类型,以砂质粉砂为主,其次为粉砂与粉砂质砂,再次为砂,中值粒径平均58.956μm;表层沉积物中Cr、Zn、Pb、Cu、As、Cd、Hg和TOC平均含量分别为57.6、52.6、18.7、15.3、9.14、0.130、0.0234 mg/kg和0.222%;由于河流排海物质和莱州湾内潮流运动,导致Cu、Pb、Zn、As、Cr和Cd基本呈现中部海域含量较高,西部海域高于东部海域的特征,东南部海域Cd、Hg与矿产资源的开发相关;14.3%的站位综合潜在生态风险属于中生态风险,Cd对综合潜在生态风险指数的贡献率最高,为主要潜在生态风险因子;研究区域中重金属Cu、Zn含量的分布与沉积物粒径和有机碳的含量密切相关。     

Spatial distribution and behavior of dissolved selenium speciation in the South China Sea and Malacca Straits during spring inter-monsoon period

Selenium(Se) has been recognized as a key trace element that is associated with growth of primary producers in oceans. During March and May 2018, surface water(67 samples) was collected and measured by HG-ICP-MS to investigate the distribution and behavior of selenite [Se(IV)], selenate [Se(VI)] and dissolved organic selenides(DOSe) concentrations in the Zhujiang River Estuary(ZRE), South China Sea(SCS) and Malacca Straits(MS). It showed that Se(IV)(0.14–3.44 nmol/L) was the dominant chemical species in the ZRE, related to intensive manufacture in the watershed; while the major species shifted to DOSe(0.05–0.79 nmol/L) in the MS, associated with the wide coverage of peatland and intensive agriculture activities in the Malaysian Peninsula. The SCS was identified as the northern and southern sections(NSCS and SSCS) based on the variations of surface circulation.The insignificant variation of Se(IV) in the NSCS and SSCS was obtained in March, potentially resulting from the high chemical activity and related preferential assimilation by phytoplankton communities. Contrastively, the lower DOSe concentrations in the SSCS likely resulted from higher primary production and utilization during March. During May, the concentration of Se(IV) remained low in the NSCS and SSCS, while DOSe concentrations increased notably in the SSCS, likely due to the impact of terrestrial inputs from surface current reversal and subsequent accumulation. On a global scale, DOSe is the dominant Se species in tropical oceans, while Se(IV) and Se(VI) are major fractions in high-latitude oceans, resulting from changes in predominated phytoplankton and related biological assimilation.     

Using triple oxygen isotopes and oxygen-argon ratio to quantify ecosystem production in the mixed layer of northern South China Sea slope region

Quantifying the gross and net production is an essential component of carbon cycling and marine ecosystem studies.Triple oxygen isotope measurements and the O_2/Ar ratio are powerful indices in quantifying the gross primary production and net community production of the mixed layer zone,respectively.Although there is a substantial advantage in refining the gas exchange term and water column vertical mixing calibration,application of mixed layer depth history to the gas exchange term and its contribution to reducing indices error are unclear.Therefore,two cruises were conducted in the slope regions of the northern South China Sea in October 2014(autumn) and June 2015(spring).Discrete water samples at Station L07 in the upper 150 m depth were collected for the determination of δ~(17)0,δ~(18)O,and the O_2/Ar ratio of dissolved gases.Gross oxygen production(GOP) was estimated using the triple oxygen isotopes of the dissolved O_2,and net oxygen production(NOP) was calculated using O_2/Ar ratio and O_2 concentration.The vertical mixing effect in NOP was calibrated via a N_2O based approach.GOP for autumn and spring was(169±23) mmol/(m~2·d)(by O_2) and(189±26) mmol/(m~2·d)(by O_2),respectively.While NOP was 1.5 mmol/(m~2·d)(by O_2) in autumn and 8.2 mmol/(m~2·d)(by O_2) in spring.Application of mixed layer depth history in the gas flux parametrization reduced up to 9.5% error in the GOP and NOP estimations.A comparison with an independent O_2 budget calculation in the diel observation indicated a26% overestimation in the current GOP,likely due to the vertical mixing effect.Both GOP and NOP in June were higher than those in October.Potential explanations for this include the occurrence of an eddy process in June,which may have exerted a submesoscale upwelling at the sampling station,and also the markedly higher terrestrial impact in June.     

赤峰托河盆地流纹岩年代学、地球化学特征及其地质意义

赤峰托河火山盆地位于大兴安岭南端内蒙古赤峰市克什克腾旗境内,处于西拉木伦河-长春缝合带以南、康宝-围场-赤 峰-开源断裂带以北的辽源地块,盆地中的长英质火山岩系角度不整合于下二叠统额里图组、于家北沟组之上,并被新近系汉诺 坝组玄武岩不整合覆盖。SHRIMP 锆石U-Pb年龄表明,盆地火山岩系中流纹岩锆石的206Pb/238U年龄为158.5±1.3 Ma,属晚侏罗 世早期岩浆活动的产物,应归入新民组。托河流纹岩具有较高的SiO2含量（68.6%~72.6%）,A/CNK值<1.1,标准矿物刚玉的含量< 1%;ΣREE含量较高,轻稀土富集,负铕异常显著;(87Sr/86Sr)i= 0.709244~0.713168,εNd(t)=-8.76~-8.42,TDM2=1656~1629Ma,(206Pb/ 204Pb)i=17.271~17.326,(207Pb/204Pb)i=15.401~15.413,(208Pb/204Pb)i=37.614~37.696,δ18OV-SMOW=4.1‰~4.5‰。经对比托河盆地流纹岩与 红山子盆地、芝瑞盆地流纹岩、流纹斑岩,它们主量元素、微量元素和Sr-Nd-Pb-O同位素地球化学特征基本一致,指示各盆地的 物质来源相同。文章证实赞同前人提出的物质来源既与地壳（特别是下地壳）有关,也与地幔特别是EMI型地幔有关的观点。在 (Yb+Ta)-Rb和Y-Nb图解上,托河盆地流纹岩均显示板內拉张的构造环境。类比红山子盆地的岩石组合、地质时代、同位素组 成、铀矿化特征等,提出托河盆地条件更优越,认为今后盆地内的铀矿勘查工作可参照红山子铀钼矿床的模式开展。     

基于模型约束的Kirchhoff积分法叠前深度成像

与时间域偏移方法比较,叠前深度偏移成像方法能够适应剧烈横向速度变化、陡倾角反射的地震资料。本文通过研究Kirchhoff叠前深度偏移方法成像原理,首先建立初始速度模型;然后在初始速度模型中加入了目标地质体--盐丘作为层位,对初始速度模型进行优化,在层位的约束下通过多次迭代计算,对优化前后的两个速度模型求取旅行时差更新初始速度模型;最后利用更新后的初始速度模型进行Kirchhoff积分法叠前成像。叠前时间偏移和模型约束下的Kirchhoff积分法叠前深度偏移成像结果显示,后者成像具有更高的信噪比和分辨率。     

曼氏血吸虫宿主藁杆双脐螺与几种扁蜷螺形态解剖学比较

曼氏血吸虫中间宿主螺藁杆双脐螺和其他3种隶属扁蜷螺科的吸虫及线虫中间宿主螺,其形态极为相似,缺乏分类学资料,比较几种扁蜷螺的形态及生殖系统构造,明确其分类学特征,能为监测及防控部门准确鉴定物种提供依据。电子数显卡尺测量所有样本螺壳参数;解剖4种扁蜷螺生殖系统并绘图;扫描电镜观察齿舌形态。方差分析表明,4种扁蜷螺壳高(H)和直径(D)比值差异显著(F=64.171,P0.01)。4种扁蜷螺齿舌均为中央齿1列,双齿型,但中央齿齿尖形态、侧齿及缘齿列数、齿尖数量及形态等依种类不同均有差异。研究结果表明不同种的齿舌形态是重要鉴别特征之一。生殖系统阴茎复合体构造在属间差异明显,种间较为相似(旋螺属的凸旋螺、小旋螺)。尽管4种扁蜷螺贝壳形态较为相似,但壳高(H)和直径(D)比值、齿舌列数、齿尖以及生殖系统的阴茎复合体构造等特征,对入侵物种藁杆双脐螺和中国几种常见扁蜷螺的准确鉴定有重要价值。     

The influence of increased iron concentration on survival and growth of seedlings and young plants of eelgrass Zostera marina

Iron (Fe) is an essential nutrient for plants but toxic at high concentrations. We subjected seedlings and young plants of eelgrass Zostera marina to different seawater iron concentrations (500, 600, 700, 800, 1,000 and 1,500 μg/L) for 30 days under controlled laboratory conditions. Natural seawater without added iron (500 μg/L) was used as reference seawater. No sediments were provided to avoid iron scavenging by particle surfaces in the sediment. We measured plant response in terms of survivorship, morphology, growth rate and productivity. Survival analysis combined with morphological, dynamic and productive assessment suggested that the optimum seawater iron concentration for the establishment of Z. marina seedlings and young plants is 700 μg/L. The no observed effect concentration, lowest observed effect concentration, lethal concentration that caused an increase in mortality to 10% of that of the control, and the effect concentration that caused a decrease in growth to 10% of that of the control values of young plants were significantly lower than those of seedlings, implying an increased sensitivity to high Fe concentrations (>1,000 μg/L). This study further develops our understanding of the physiological ecology of the early life stages of Z. marina and provides data that could prove helpful in the development of successful eelgrass restoration and conservation.