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1.
李跃清 《成都信息工程学院学报》1999,(1)
应用ＳＶＤ技术，诊断分析了北半球１００ｈＰａ高度场与川渝地区夏季降水的关系。结果表明：高度场与降水场具有密切的时空相关性，第一模态反映了两场间的主要耦合特征；南亚高压活动地区前期１０～１２月、１～４月高度场变化，通过影响未来夏季南亚高压强度、位置，导致川渝地区夏季旱涝异常。高度场与降水场的这种非同步联系，物理意义明确，时空相关显著，是一种有价值的预测川渝地区夏季旱涝异常的强信号。 相似文献
2.
河口捕获平均全长２．５ｃｍ的天然花鲈苗种，分二阶段进行培育。第一阶段是流水淡化驯养：包括淡化、暂养和驯饵；第二阶段是分级培育，每隔４～６ｄ分筛分级一次，直至４～６ｃｍ的鱼种。试验总成活率是５５％。 相似文献
3.
采用室内水泥池及活饵培育配套技术进行尖吻鲈苗种阶段工厂化育苗。投放刚孵化出膜的仔鱼１６０万尾，经室内池８ｄ的培育，成活率为９０％；经１３ｄ的培育其规格超过１ｃｍ，成活率为５６．９％；经２４ｄ的培育平均规格达２ｃｍ左右，平均成活率为５０％，共育出８０万尾。苗种生长快，体质健壮，成活率高。关键技术是：基础设施配套；采用不同活饵，做到适口、及时转化、足量；定期过筛分级培育；水质控制良好；注意防病。２ｃｍ以上鱼种阶段采用多种方式培育，经１５～２０ｄ的饲养，规格达３～４ｃｍ，平均成活率为６５％～７５％。 相似文献
4.
利用１９８０～１９８２年的资料，揭示了夏季青藏高原上存在准１周、准半周和准１０ｄ的大气短周期振荡，而且这种振荡与高原东部有限区域的低涡活动及下游降水有较好的超前相关 相似文献
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针对目前大批低产老化虾池的改造和可持续生产的问题，设计了一个自然生态养虾新模式。利用长期不能清淤的低产老化虾池和已造成生态失衡的虾池，实行疏放苗，精管理，综合利用、立体开发，混养、轮养。试验结果表明，养殖周期为 ８０～９０ ｄ，对虾成活率６０．５％ ～７６％ ，体长达１０．１～１３．２ ｃｍ ，平均体重 １７．２～１９．２ ｇ／尾，饵料系数 ０．７７～０．８０，平均产量 ６４５～７８０ ｋｇ／ｈｍ ２，鲻鱼产量 ４２０～４６５ ｋｇ／ｈｍ ２ 。整个养殖过程虾池的各种水质理化因子基本符合要求，从而使对虾养殖在一种相对稳定的生态环境中进行 相似文献
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以主要鲜切花品种马蹄莲、香石竹为材料，用常规观测气象资料与其产量波动和质量进行相关分析。结果表明：日照时数和气温对笠年春季出花数有滞后作用。马蹄莲花茎高度与日平均气温１０～２５℃有效积温成对数关系，达优质花高度还需一定营养体大小。气温和日照时数对香石竹产量波动有一定影响 相似文献
7.
斑节对虾虾苗白斑综合症杆状病毒的检测和养殖跟踪 总被引：1，自引：0，他引：1
利用２步ＰＣＲ检测技术对湛江和阳西地区的虾苗进行白斑综合病杆状病毒（ＷＳＳＶ）检测。在仔虾２日龄最早检测得到病毒，有２５％的虾苗带有ＷＳＳＶ病毒。带病毒虾苗和不带病毒虾苗分别在不同养殖模式的养殖过程中跟踪。前者在湛江湖光镇普通虾塘跟踪养殖，它们在变化的环境中容易发病，ｐＨ、盐度和温度是重要的诱发因子，在养殖５０～６０ｄ时发病死亡；后者在高位池和普通池养殖跟踪，它们对变化的环境有较大的适应性，养殖时间为８０～１１０ｄ，在相对优良的养殖技术条件下大部分可望养殖成功。环境中有ＷＳＳＶ病原传入，不带病毒虾苗在养殖后期可以带有ＷＳＳＶ病毒，出现白斑虾。跟踪有普通池有爆发病害，但是时间延后，跟踪的高位池没有爆发病害。 相似文献
8.
本文从大气能量平衡方程和海温变化方程出发,得到海～气耦合的多频振荡系统,分析此多频系统的特殊频率方程得到: 1)当大气视为非定常,海洋视为定常的情况下,得到的波动本质上是非绝热的Rossby波。 2)当大气定常,海洋非定常的情况下,得到两类性质相异的波动;一类是周期为准半年(4～9月)的非绝热慢波,另一类是周期为准两年(2～3年)的非绝热慢波;两类慢波的传播方向完全相反,准两年波比准半年波传播得更慢(两者几乎相差一个量级)。 相似文献
9.
利用MHAT小波变换分析和灰色拓扑预测方法对海南琼海1953—2007年55年的暴雨频次的变化特征进行分析，结果表明，暴雨频次分别存在2a、6a、8a的准周期变化，8a准周期在20世纪70年代初期和80年代初期的信号最强，但1990年代后，暴雨频次较降水量出现了更多的小尺度周期波动扰动，表明极端降水事件有频繁出现的趋势。暴雨频次的季节变化主要体现在夏秋两季的暴雨多发季节，夏季主要存在2a、6a、12—13a、18a左右的准周期，秋季主要存在2—3a、8—9a、12a、17—18a左右的准周期，并且在各个季节表现出多时间尺度交替的复杂结构变化的非周期性特征，能在一定程度上解释暴雨频次较为异常的状况。琼海大暴雨和特大暴雨主要发生在秋季原因，可能与西行热带气旋和南下弱冷空气共同影响海南岛，同时配合偏东回流的环流背景有很大关系。文中基于小波分析和灰色预测方法的研究结果，提供了琼海地区暴雨预报和防灾减灾的一定科学依据。 相似文献
10.
极地平流层位势高度变化与中国冬季气温的关系 总被引：1，自引：0，他引：1
平流层异常对于对流层的影响研究,尤其是将平流层的异常信号加入中长期天气预报已成为近年来的研究热点。首先利用NCEP/NCAR再分析资料和国家气候中心提供的160站气温资料,采用SVD方法深入分析平流层位势高度场与中国冬季气温的关系。结果表明,极涡与中国东北地区温度有着非常密切的联系。即当中高纬地区位势高度场减弱时(极涡增强),东北地区的温度上升;中高纬地区位势高度场增强时(极涡减弱),东北地区的温度下降。进一步通过挑选出的6个东北亚型强极涡年,6个北美型强极涡年和8个弱极涡年,分别对冬季位势高度场和温度场进行合成分析、小波分析和交叉谱分析。结果发现,东北亚型强极涡和中国东北地区冬季气温的关系最为密切,平流层关键区位势高度场和东北地区地面温度场都有着50天左右的振荡周期,并且关键区位势高度场的季节内振荡有着超前于温度场的特征;北美型强极涡和东北地区温度的联系较小;弱极涡与东北地区温度的关系也不太明显。 相似文献
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12.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature. 相似文献
13.
《极地研究(英文版)》2014,(4)
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose 相似文献
14.
《中国海洋大学学报(英文版)》2014,(4)
<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail 相似文献
15.
《中国海洋大学学报(英文版)》2014,(6)
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo- 相似文献
16.
Massimo GRECO 《山地科学学报》2014,(6):1383-1384
<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a 相似文献
17.
As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m. 相似文献
18.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area. 相似文献
19.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter. 相似文献
20.
《极地研究(英文版)》2014,(3)
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied 相似文献