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1.
利用2009年9-10月及2010年5-6月在绥芬河干、支流采集标本,初步研究了高体鮈、拉氏和湖3种鱼类的生物学特性.结果表明:(1)高体鮈渔获物体长范围是48.0-137.0mm,体重范围是1.8-36.8g;拉氏标本渔获物体长范围是24.0-138.0 mm,体重范围是0.3-40.1g;湖渔获物体长范围是32.0-88.0 mm,体重范围是0.4-10.5 g;(2)高体鮈丰满度范围为0.96-2.45;拉氏丰满度范围为0.84-3.00;湖的丰满度则在1.16-2.23之间;(3)高体鮈和拉氏均由三个龄组组成,其中1龄和2龄为优势龄组,其相对多度分别为92.64%和97.44%;湖仅含两个年龄组;(4)三种鱼类均在1龄时生长速度最快,其体长的绝对生长速度分别为64.33mm/y(高体鮈)、41.46 mm/y(拉氏)和52.56 mm/y(湖);(2)体长与体重的关系式为:W=11.06×10-5L2.57(高体鮈),W=3.67×10-5L2.81(拉氏)和W=7.91×10-5L2.65(湖);(5)雌:雄性比分别为1.1◇1(高体鮈),0.75◇1(拉氏),0.48◇1(湖);最小性成熟年龄均为2龄;(6)高体鮈、拉氏的绝对繁殖力分别为4,270-7,200粒、1,679-2,610粒和2,264-2,871粒;相对繁殖力分别为514-1,019粒/g、156-193粒/g和282-485粒/g。  相似文献   

2.
本文报道了湘西棘腹蛙人工饲养的初步结果.试验结果表明,成蛙的日食量平均为体重的4.47%;幼蛙的日食量平均为体重的4.86%.成蛙和幼蛙的饵料系数平均为4.1±0.1;蝌蚪的饵料系数平均为3.66.40~50克体重的幼蛙,平均日增重为2%.使用多成分混合性饵料饲养蝌蚪,其体长和体重增长显著.  相似文献   

3.
上海地区淡剑夜蛾发生规律及其防治   总被引:1,自引:0,他引:1       下载免费PDF全文
淡剑夜蛾一年发生4—5代,以老龄幼虫在草坪根部表面层越冬.1龄、2龄、3龄、4龄、5龄、6龄幼虫头壳宽分别为0.33±0.13mm,0.60±0.07mm,0.93±0.10mm,1.28±0.20mm,1.66±0.10mm,1.92±0.13mm.幼虫期总食叶量为52.17cm^2.雌雄性比1:1.24.在室外喷雾2000倍20%杀灭菊脂、2000倍20%米满、4000倍20%除虫脲、2000倍10%除尽、4000倍5%氯氰菊酯、1000倍25%灭幼脲三号和6000倍1%阿维菌素7d后的校正死亡率分别在85.60%-96.20%.  相似文献   

4.
西施舌稚贝对3种微藻选择性及摄食率研究   总被引:7,自引:0,他引:7  
对西施舌稚贝的摄食率及藻类选择性变化进行研究.结果表明,西施舌稚贝对直径11.2 μm四爿藻具有较高的选择性,而对云霄微型藻和牟氏角毛藻的摄食率均偏低.西施舌稚贝对四爿藻的摄食率在第5 h时达到最高值(174.928×10-5mg·h-1).当西施舌稚贝分别摄食3种藻类时,在适宜的藻类密度范围内,摄食率均随着藻类密度的增大而迅速增加,当藻类密度达到一定值后,摄食率呈下降趋势.西施舌稚贝摄食率与藻类密度之间关系适用二次多项式表示.  相似文献   

5.
西施舌稚贝与仿刺参幼参混养的研究   总被引:1,自引:0,他引:1  
在控制水温25℃下,设置5组壳长(4.83±0.14)mm,质量(0.041±0.004)g的西施舌稚贝,每组249粒,分别混养湿质量(0.524±0.010)g的仿刺参5,10,15,20头,设无刺参的西施舌单养组作为对照.经30d的饲养,各组西施舌成活率均较高,在89%以上.混养西施舌壳长的生长较单养有显著差异(P<0.05),混养组间西施舌壳长差异不显著(P>0.05).H15西施舌壳长增长最多为(9.03±0.21)mm,西施舌的质量生长方面,单养和混养以及混养组间都差异极显著(P<0.01).H15西施舌增重最大为(0.490±0.107)g,混养的刺参成活率为100%,至实验结束,H05和H10组刺参质量呈先增长后下降的趋势;H15则持续增长;H20一直呈现负增长.  相似文献   

6.
报道了湘西地区棘腹蛙(R.bouLengeri G.)幼蛙人工试养的研究,结果表明:各龄幼蛙的日食量平均为体重的3.07%,饵料系数随着年龄增加而加大,平均为3.66;试验中幼蛙的年龄与饲养密度对其体重的增长及成活率的影响明显;不同饲养密度的幼蛙成活率为77.50%~100%;刚变态的幼蛙体长平均为1.98厘米,体重平均为0.95克;经过两周年饲养,体重平均为20.50克,体长平均为5.81厘米,体长与体重的增长曲线呈“S”型。  相似文献   

7.
为确定鸡球虫病的发病规律 ,进行了人工感染试验 ,将 78只 1 4日龄公雏随机分成 6组 ,第 1组为对照组 ,第 2~ 6组分别按 6× 1 0 4 、1 2× 1 0 4 、1 8× 1 0 4 、2 4× 1 0 4 、30× 1 0 4 个 /只人工感染孢子化混合卵囊 ,观察其临床症状和病理变化 ,并测定O P G值和Hb含量。结果表明 ,感染后第 3天 ,感染组均开始食欲下降 ;第 4天排出血便 ,高峰期在感染后 5~ 6d ;感染后第 4天有卵囊排出 ,O P G值在第 7天达高峰 ;病变出现在十二指肠和盲肠 ;感染后 4~ 6d的Hb含量显著下降。其中以第 5、第 6组临床表现最为严重 ,死亡率均为 2 3 0 8%。  相似文献   

8.
经过3a实践研究,重点突破了青蛤亲贝强化培育与人工催产技术,幼虫饵料单胞藻培育技术,青蛤苗种中间培育与清涂除害技术,系统掌握生产性育苗及中间培育技术,实现了青蛤苗种的规模化生产。2003 ̄2005年累计培育平均壳高2 mm的稚贝74.574亿粒,经中间培育后出池商品仔贝49.842亿粒,中间培育成活率达到66.84%。生产性育苗净利润163.82万元,中间培育总利润776万元,获利15 089元/km2。  相似文献   

9.
2011年5月和2016年5月份在烟威渔场采集了320尾和248尾小黄鱼标本,研究了小黄鱼产卵群体生物学特征,主要包括:体长组成、体重组成、性比和绝对繁殖力.结果表明:2011年小黄鱼产卵群体体长106~230 mm,体重13~114 g,绝对繁殖力F3 211~23543粒,平均(12 636±1 210)粒/尾;2016年小黄鱼产卵群体体长102~207 mm,体重12~110 g,绝对繁殖力F4 960~19 697粒,平均(10 705±855)粒/尾.与历史资料相比较,小黄鱼的繁殖力水平有减小的趋势.  相似文献   

10.
闽江口及附近海域棘头梅童鱼的生物学特征   总被引:4,自引:0,他引:4  
利用2006年8月至2007年10月4个季度月的底拖网调查数据,初步分析了闽江口及附近海域底拖网渔获物中棘头梅童鱼的生物学特性.结果表明:1)棘头梅童鱼体长与体重的关系式为:W=1.228 4×10-5L3.102 3(R2=0.973 0,n=736),体长生长方程为:Lt=183.75[1-e-0.60(t+0.27)],体重生长方程为:Wt=125.90[1-e-0.60(t+0.27)]3.102 3;2)优势体长组为100~120 mm,优势体重组有两个,分别为0~5 g和25~30 g,体重生长拐点为1.62龄;3)性腺分化和性成熟时间在冬季、春季,摄食强度在春季、夏季较强.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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