Effect of UV-B radiation on the population dynamics of the rotifer Brachionus urceus     

WANG Jinhe  FENG Lei  TANG Xuexi 《海洋学报(英文版)》2011,30(2):113-119

The effect of UV-B radiation enhancement at experimental doses of 0.00,0.24,0.48,0.72,0.96,and 1.20 kJ/m 2 on the population dynamics of the rotifer Brachionus urceus feeding on the alga Chlorella sp.was studied under controlled laboratory conditions using clonal culture and life-table techniques.The results show that UV-B radiation treatment significantly shortened the survival time of the rotifer (P <0.05): The longest survival time (336 h) occurred in the control (0.00 kJ/m 2 ) while the shortest (222 h) occurred when exposed to the highest UV-B radiation treatment (1.20 kJ/m 2 ).The fecundity of the rotifer B.urceus was enhanced by the lower UV-B radiation treatment (0.24 and 0.48 kJ/m 2 ) but inhibited by the higher treatments (0.96 and 1.20 kJ/m 2 ).Life expectancy also was obviously affected by UV-B radiation (P <0.05).The highest life expectancy occurred in the control (0.00 kJ/m 2 ),and it became shorter with increasing doses of UV-B radiation.The resutls in the present study indicate that the life expectancy of the rotifer B.urceus can be used as an indicator for UV-B radiation enhancement.  相似文献   

藏南地区晚白垩世岩相古地理初步研究          下载免费PDF全文

熊国庆  江新胜  伍皓 《古地理学报》2011,13(4):387-396

通过对藏南地区上白垩统沉积特征及沉积相进行综合分析,初步地恢复了该地区晚白垩世岩相古地理.该地区自南向北沉积水体逐步变深,沉积相带展布依次为滨海相、浅海陆棚相(外陆棚和内陆棚亚相)、大陆斜坡相及深海盆地相,局部地区浅海陆棚相之上发育碳酸盐岩礁滩相和孤立台地相等.盆地性质总体上仍然为被动大陆边缘海盆,但已具备周缘前陆盆地...  相似文献   

上海地学研究：从长江口到深海——中国科学院院士汪品先教授接受本刊专访     

《上海国土资源》2011,32(3):1-6

2011年8月30日下午,本刊主编、上海市地质调查研究院总工程师严学新教授,本刊编辑部主任、上海市地质调查研究院总工程师办公室副主任龚士良教授,在同济大学海洋与地球科学学院杨守业教授的陪同下,拜访了中国科学院院士、同济大学海洋与地球科学学院汪品先教授,并作了专题访谈。  相似文献   

Sedimentological criteria to differentiate submarine channel levee subenvironments: Exhumed examples from the Rosario Fm. (Upper Cretaceous) of Baja California, Mexico, and the Fort Brown Fm. (Permian), Karoo Basin, S. Africa     

Ian A. Kane  David M. Hodgson 《Marine and Petroleum Geology》2011,28(3):807-823

Two scales of levee confinement are commonly recognised from submarine channel-levee systems on the seafloor and in the subsurface. Large-scale external levees bound the entire system whilst smaller-scale internal levees bound individual thalweg channels within the channel-belt. Although thin beds are commonly identified in core and well logs, their origin, and consequently their stratigraphic significance is currently poorly understood. This knowledge gap stems, in part, from the lack of unambiguously identified outcrop analogues of channel-levees, and in particular the lack of identifiable internal and external levees. Here we report from two exhumed channel-levee systems where both scales of confinement can be recognised: the Rosario Fm. of Baja California, and the Fort Brown Fm. of South Africa. A suite of characteristic sedimentary features are recognised from internal and external levees respectively: internal levees are characterised by structures indicative of complexity in the waxing-waning style of overspill, interactions with topography and flow magnitude variability; in contrast, external levees are characterised by structures indicative of simple surge-like waning flows, relatively uniform flow directions, laterally extensive beds, and a lack of erosive events. Using these observations, together with published literature, we propose a simple nomenclatural scheme for levee sub-environments, and criteria to differentiate between levee sub-environments in core or outcrop.  相似文献   

The role of international environmental instruments in enhancing transboundary marine protected areas: An approach in East Africa     

José Guerreiro  Aldo Chircop  David Dzidzornu  Catarina Grilo  Raquel Ribeiro  Rudy van der Elst  Ana Viras 《Marine Policy》2011

The increasing degradation of marine ecosystems has led to multiple calls for greater protection through the establishment of marine protected areas (MPAs). If created at the ecosystem or ecoregion level, MPAs will likely straddle maritime boundaries and therefore necessitate international cooperation. International environmental law and international law of the sea may facilitate cooperation between States in creating transboundary MPAs. The extent to which this body of law is actually or potentially useful for the establishment of transboundary MPAs is examined in the context of the East African Marine Ecoregion, focusing on Mozambique, South Africa, and Tanzania. A general survey and assessment of the applicable global, regional, and bilateral instruments in relation to the three States is conducted. Although some global instruments are relevant in the East African context, regional and bilateral instruments are more conducive to the establishment of transboundary MPAs. The article concludes that although a trilateral agreement between Mozambique, South Africa, and Tanzania would be an ideal vehicle for the establishment of a transboundary network of MPAs addressing both national and ecoregional conservation interests, a separate solution at each border will be the first step towards this goal.  相似文献   

温度对凡纳滨对虾幼体生长、变态和存活率的影响   总被引：1，自引：0，他引：1  

杨章武  卢小宁  郑雅友  李正良 《台湾海峡》2011,30(1):81-85

通过不同水温的比较实验,研究了凡纳滨对虾人工育苗的适宜水温,旨在了解33℃及其以上水温对凡纳滨对虾幼体生长、变态和存活率可能造成的不良影响.实验结果表明,在29、31、33、35℃这4种温度实验组中,33℃组幼体的生长最快.Z1—P15期幼体的存活率以31℃组的最高（为29.8%）,其次是33℃组（为20.9%）,35℃组的最低（为4.7%）.实验过程中31℃组幼体的活力状态最佳、最稳定.因此,31℃左右是凡纳滨对虾幼体生长、发育的适宜水温.考虑到33℃组幼体的总存活率虽然低于31℃组,但其具有生长较快的优势,因此可认为目前凡纳滨对虾人工育苗普遍采用的31～32℃水温是合适的.  相似文献   

0903号台风“莲花”的风结构分析     

张加春  饶灶鑫  陈煜  蔡巧晖 《台湾海峡》2011,30(4):507-511

通过对0903号台风“莲花”在登陆福建晋江并沿着海岸线北上过程中的沿海自动站逐时实况风场资料的分析,研究了该台风的风结构状况,得到以下结论：（1）台风近中心最大风速预报值比实测风速偏小,台风7级风半径则比实际的偏大．（2）实测2min平均风速最大值（Vmax）总体上呈减弱趋势,与时间（t）的回归方程式为：Vmax=28．9—0．61t（n=16,r=0．78,r005=0．50）．（3）台风最大风速半径（R）呈逐渐扩大的趋势,与时间（t）的回归方程式为：R=28．28—4．98t＋0．67t。（n=16,r=0．95,r0.05=0．50）．（4）台风最大风速区位于台风后部．认识台风风结构,有助于不断地提高预报的准确性．  相似文献   

孟加拉笛鲷与四带笛鲷的微卫星分析     

李培  王中铎  郭昱嵩  刘丽  刘楚吾 《台湾海峡》2011,30(4):517-521

采用聚丙烯酰胺凝胶电泳技术,从西大西洋笛鲷（Lutjanuscampechanus）和勒氏笛鲷（L．russel—lii）的微卫星引物中筛选出适用于孟加拉笛鲷（L．bengalensis）和四带笛鲷（三．kasmira）的微卫星引物,并应用于三亚和湛江群体的遗传结构分析．结果表明：25对引物中筛选出13对可以稳定扩增出特异片段的引物,其中12对可在孟加拉笛鲷基因组中扩增出重复性好的特异性条带;10对可在四带笛鲷中扩增出重复性好的特异性条带,并且全部呈现出种内多态;9对为两个种通用．孟加拉笛鲷的湛江群体（zMJ）和三亚群体（SMJ）、四带笛鲷的湛江群体（ZSD）和三亚群体（SSD）的平均等位基因数分别为：3．8889、4．1111、4．3333、4．2222;平均观测杂合度分别为：0．5833、0．6389、0．5944、0．6389;平均多态信息含量分别为：0．4720、0．4692、0．5474、0．5257．将本实验所得结果与笛鲷鱼其他研究结果进行比较分析,可以看出目前湛江海域野生笛鲷的遗传多样性整体比较丰富,但部分野生笛鲷已表现出杂合子缺失的趋势,这势必会引起将来遗传多样性的降低,所以要尽旱对野生群体进行摸底调查。并找出解决养殖群体污染野生群体这一问题的方法．  相似文献   

深海沉积物宏基因组文库中产蛋白酶克隆CAPRO2的筛选及酶学性质分析     

徐辉  赵晶  曾润颖 《台湾海峡》2011,30(4):522-527

利用选择性筛选培养基从所构建的深海沉积物宏基因组文库中筛选得到一株产蛋白酶的克隆（CAPR0002）,对其进行了酶学性质分析．结果表明该酶的最适作用温度为65cc,最适作用pH值为9．0．该蛋白酶具有较好的热稳定性,在40cC以下的温度中可长期保持稳定,在50℃中处理6h后仍能保持60％的活力,在60℃下保温30rain后仍能保持约60％的活力．Ca^2＋、Mg^2＋、sr^2＋、co^2＋对该蛋白酶有明显的促进作用,而且ca^2＋的存在可明显提高该蛋白酶的热稳定性,ca^2＋、sr^2＋、c0^2＋这3种离子均在3．0mmol／dm^3。浓度时具有最高的促进作用,当浓度高于3．0mmol／dm’时,这3种离子对酶活力的促进作用减弱．Hg^2＋、Fe^2＋、cu¨对酶有明显的抑制作用．CAPR02蛋白酶在pH值为7。5～9．5时活力较高,pH值为7。5时可保持约80％的活力,pH值为9．5时保持60％的活力,而在pH值高于9．5的条件下酶活力下降较快,pH值为10．0时活力降为约15％,表明CAPR02属于碱性蛋白酶．丝氨酸蛋白酶抑制剂PMSF、E一64和AEBSF对CAPR02蛋白酶均无抑制作用,显示该酶不属于丝氨酸蛋白酶,而EDTA对酶有明显的抑制作用,表明该酶属于金属蛋白酶．  相似文献   

盐度对日本鳗鲡生长及非特异性免疫酶活性的影响   总被引：2，自引：0，他引：2  

胡利华  闫茂仓  郑金和  李小勇  黄贤克  王侃  周朝生 《台湾海峡》2011,30(4):528-532

利用实验生态学和酶学方法,在浙江省海洋水产养殖研究所清江试验场研究了盐度对平均体长为25．1±5．6cm的日本鳗鲡（Anguillajaponica）生长及其血清溶茵酶（LZM）、超氧化物歧化酶（SOD）及碱性磷酸酶（AKP）活性的影响,实验持续60d．实验设置了5个盐度梯度（盐度5、10、15、20、25）和对照组（盐度0）,每梯度设3个平行组,各组盐度和pH值保持一致．日本鳗鲡血清中免疫酶活力指标：碱性磷酸酶、溶茵酶、超氧化物歧化酶在实验的第7天和第14天测定．实验结果表明,盐度5组相对增重率最高（279．78％±28．37％）,其次是盐度10组（278．74％±22．25％）,盐度15、20、25组相对增重率分别为234．39％±21．28％、230．28％±26．31％、228．01％±29．29％．对照组相对增重率为233．20％-4-25．18％,盐度5和10组与对照组差异显著（P〈0．05）,其余各组与对照组差异不显著．第7天和第14天,盐度10组碱性磷酸酶活性最高,分别为225．05U／dm。和251．11U／dm’,其次是盐度5组,分别为221．76U／dm。和236．01U／dm。,显著高于对照组（P〈0．05）．第7天和第14天盐度20、25组溶菌酶活性显著高于对照组（P〈0．01）．超氧化物歧化酶随着盐度的升高呈逐步上升趋势．第14天,盐度20、25纽溶菌酶活性仍保持较高水平,SOD回落至对照组水平,而各组AKP较第7天略有上升．  相似文献