华北克拉通西北缘中元古代火山岩特征与成矿作用   总被引：1，自引：1，他引：0  

徐贵忠  王艺芬  佘宏全  边千韬  周瑞  罗小全 《地质论评》1999,45(7):495-502

华北克拉通西北缘中元古代火山岩分布在狼山和渣尔泰山地区,并产在中元古界渣尔泰山群中,主要属正常岩石系列的基性岩石。其岩石化学和地球化学特征表明该套火山岩为低钾—中钾玄武岩,并与大洋拉斑玄武岩类似。反映了中元古代火山活动是发生在狼山—渣尔泰山南、北两支裂陷槽发育的强烈裂陷阶段。岩石、矿石和矿物的稳定同位素、稀土和微量元素特征揭示,本区大型—超大型铜多金属矿床的形成与中元古代岩浆活动密切相关。  相似文献   

A potential source of recruitment of Acartia pacifica nauplii: viable benthic resting eggs   总被引：4，自引：0，他引：4  

WANG Guizhong  JIANG Xiaodong  LI Shaojing  WU Lisheng  WU Dingxun 《海洋学报(英文版)》2005,24(2)

1 Introduction M any estuarine and coastal copepods that havepreviously been classified as holoplankton m ightbestbe described as adultm eroplankton since they actuallyspend a portion oftheir life cycle in the seabed as rest-ing eggs [review ed by G rice and M arcus (1981) andM arcus (1996)]. R esting eggs can be extrem ely abun-dant (106 m ) in bays and estuaries especially w here -2w aterdepths are less than 20 m (M arcus,1989).Theyare likely to profoundly influence the dynam ics ofpel…  相似文献   

The experimental studies on the carbon and nitrogen budgets of Pseudeuphausia sinica     

Guo Donghui  Li Shaqjing  Chen Feng  Wang Guizhong  Chen Gang 《海洋学报(英文版)》2003,22(2):265-272

Abstract-The carbon and nitrogen budgets were estimated on the adult females, juveniles and post-furcilia larvae of Pseudeuphausia sinica fed on newly hatching nauplii of Artemia salina in the laborato-ry. It was found that the ingestion rate was linearly related to the food concentration, suggesting highfeeding potential. The linear correlation could be established between the respirating rate (carbon con-sumption rate) and carbon ingestion rate, as well as carbon assimilation rate. The regression coefficients(i.e.specific dynamic action coefficients) were in the range from 9% to 16% (ingested C) or 10% to17% (assimilated C) respectively, with lower in the post-furcilia larvae. There also existed a linearcorrelation equation between estimated total nitrogen excretion rate and the rates of nitrogen ingestionand assimilation separately, except for the juveniles. The defecation rates increased with the increase ofthe ingestion rate; as a result, assimilation efficiency was not related to the ingestion rat  相似文献   

海洋浮游甲壳类分子系统学研究进展     

谭树华  曹文清  林元烧  王桂忠  李少菁 《海洋通报》2003,22(5):71-77

回顾海洋浮游甲壳类系统学研究的基础上，综述了生化水平和DNA(mtDNA和核DNA)水平的分子系统学研究现状。分子标记中DNA序列分析最为常用，其次是RFLP和RAPD分析，mtDNA主要应用于分类学、群体遗传学、种间分子进化和系统发育重建研究，而核DNA则应用于科以上较高阶元的系统发育和种内、近缘种间的遗传结构和遗传分化研究。最后对存在的问题和应用前景进行了展望。  相似文献   

The progress in the study of Arctic pack ice ecology     

何剑锋  王桂忠  蔡明红  李少菁 《极地研究(英文版)》2004,15(1):55-65

The sea ice community plays an important role in the Arctic marine ecosystem. Because of the predicted environmental changes in the Arctic environment and specifically related to sea ice, the Arctic pack ice biota has received more attention in recent years using modem ice-breaking research vessels. Studies show that the Arctic pack ice contains a diverse biota and besides ice algae, the bacterial and protozoan biomasses can be high. Surprisingly high primary production values were observed in the pack ice of the central Arctic Ocean. Occasionally biomass maximum were discovered in the interior of the ice floes, a habitat that had been ignored in most Arctic studies. Many scientific questions, which deserve special attention, remained unsolved due to logistic limitations and the sea ice characteristics. Little is know about the pack ice community in the central Arctic Ocean. Almost no data exists from the pack ice zone for the winter season. Concerning the abundance of bacteria and protozoa, more studies are needed to understand the microbial network within the ice and its role in material and energy flows. The response of the sea ice biota to global change will impact the entire Arctic marine ecosystem and a long-term monitoring program is needed. The techniques, that are applied to study the sea ice biota and the sea ice ecology, should be improved.  相似文献   

Impacts of CO₂-driven seawater acidification on survival, egg production rate and hatching success of four marine copepods   总被引：1，自引：0，他引：1  

ZHANG Dajuan  LI Shaojing  WANG Guizhong  GUO Donghui 《海洋学报(英文版)》2011,30(6):86-94

Ecological experiments were conducted to examine the effects of seawater containing elevated par- tial pressure of carbon dioxide (p CO2 800 × 10 -6 , 2 000 × 10 -6 , 5 000 × 10 -6 and 10 000 × 10 -6 ) on the survival and reproduction of female Acartia pacifica, Acartia spinicauda, Calanus sinicus and Centropages tenuiremis, which are the dominant copepods in the southern coastal waters of China. The results show that the effects of elevated p CO2 on the survival rates of copepods were species-specific. C. sinicus, which was a macro-copepod, had a higher survival rate (62.01%-71.96%) than the other three species (5.00%-26.67%) during the eight day exposure. The egg production rates of C. sinicus, A. spinicauda and C. tenuiremis were significantly inhibited by the increased p CO2 and the exposure time duration. There were significantly negative impacts on the egg hatching success of A. spinicauda and C. tenuiremis in the p CO2 2 000 × 10 -6 and 10 000 × 10 -6 groups, and, in addition, the exposure time had noticeably impacts on these rates too. This study indicates that the reproductive performances of copepods were sensitive to elevated p CO2 , and that the response of different copepod species to acidified seawater was different. Furthermore, the synergistic effects of seawater acidification and climate change or other pollutant stresses on organisms should be given more attention.  相似文献   

Abundance, biomass and composition of spring ice algal and phytoplankton communities of the Laptev Sea （Arctic）     

郑淑娴  何剑锋  王桂忠  李少菁 《极地研究(英文版)》2005,16(2):70-80

Abundance,biomass and composition of the ice algal and phytoplank-ton communities were investigated in the southeastern Laptev Sea in spring 1999.Diatoms dominated the algal communities and pennate diatoms dominated the dia-tom population.12 dominant algal species occurred within sea ice and underlyingwater column,including Fragilariopsis oceanica,F.cylindrus,Nitzschiafrigida,N.promare,Achnanthes taeniata,Nitzschia neofrigida,Naviculapelagica,N.vanhoef fenii,N.septentrionalis,Melosira arctica,Clindrothecaclosterium and Pyrarnimonas sp.The algal abundance of bottom 10 cm sea icevaried between 14.6 and 1562.2×10~4 ceils l~(-1)with an average of 639.0×10~4cells l~(-1),and the algal biomass ranged from 7.89 to 2093.5μg C l~(-1)with an av-erage of 886.9μg C l~(-1),which were generally one order of magnitude higherthan those of sub-bottom ice and two orders of magnitude higher than those ofunderlying surface water.The integrated algal abundance and biomass of lower-most 20 cm ice column were averagely 7.7 and 12.2 times as those of upper 20 mwater column,respectively,suggesting that the ice algae might play an importantrole in maintaining the coastal marine ecosystem before the thawing of sea ice.Icealgae influenced the phytoplankton community of the underlying water column.However,the“seeding”of ice algae for phytoplankton bloom was negligible be-cause of the iow phytoplankton biomass within the underlying water column.  相似文献   

快速升温后极地甲藻Polarella glacialis的生理响应          下载免费PDF全文

郑淑娴  何剑锋  王桂忠  林森杰  张芳 《极地研究》2013,25(1):61-70

Polarella glacialis最早发现于南极固定冰和北冰洋水层,最近在温带海域也发现其相关基因。专抗甲藻的Rubisco、PCNA抗体在该藻细胞内各检测到~53 kDa和~55 kDa的特异性条带。对该藻的梯度温度培养实验显示,4℃生长的P. glacialis细胞密度为1.1×105 cells/ml时仍能继续增殖,一天中藻细胞内Rubisco的表达量基本保持恒定,PCNA的表达量峰值与%S峰值相对应,当温度迅速上升至15、20℃时,藻株处于胁迫状态,细胞密度迅速减少,正常的细胞周期被干扰,大多数细胞分裂活动不活跃或停止分裂,Rubisco、PCNA的表达量大幅减少甚至消失,昼夜表达特征改变,其中20℃对藻株的胁迫作用更加显著。15℃培养下的P. glacialis细胞密度并不立即减少,细胞周期与两种指示蛋白表达特征显示仍有部分细胞完成分裂。本研究为该藻的相关基因在温带水域的出现提供了可能的解释,并推测在相对长期渐进的极地增温过程中,P. glacialis可能继续存在。  相似文献   

靖西县高山广播电视转播发射台防雷浅探     

乃远程  苏贵中 《气象研究与应用》2010,31(4)

对靖西县高山广播电视转播发射台发生雷灾事故的原因进行分析,提出高山广播电视转播发射台应该采取的防雷措施。  相似文献   

中国含煤盆地浅—中深部现今地应力特点和分布规律     

文卓  康永尚  邓泽  孙良忠  李贵中  王红岩 《地质论评》2019,65(3):729-742

在煤炭开采和煤层气勘探开发过程以及其他地质工程活动中,现今地应力是一个不可忽略的地质因素。本文收集和估算了中国六个不同含煤盆地1300 m以浅的现今地应力数据,对中国含煤盆地的浅—中深部的地应力特点和地应力分布规律展开研究。研究表明:①东部地区走滑应力场(σ_Hσ_Vσ_h)占比高,向西北地区逐渐降低;中—高应力场占比在中国各含煤盆地差异比较小;②地应力场类型和地应力量级与埋深有关,随着中国含煤盆地开采深度的增加,正常应力场(σ_Vσ_Hσ_h)逐渐占据主导作用,地应力量级也逐渐加大;③通过侧压系数对比,将现今中国含煤盆地浅—中深部地应力强度分为:东北地区高应力区、两淮地区中—高应力区、滇东黔西和沁水盆地中应力区以及鄂尔多斯盆地(东缘)和准噶尔盆地(南部)低应力区;④板块俯冲形成了中国含煤盆地地应力强度东强西弱的分布格局,南北走向的吕梁山是中国北部东西应力强度的分界线;⑤地应力强度向着远离应力源的方向减弱,这种变化规律在中国大陆以及在某个应力分区内(如在沁水盆地和滇东黔西地区)皆有表现。  相似文献