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1.
渭河上游鱼类区系研究   总被引:3,自引:1,他引:2  
本文根据近年来所采标本,对渭河上游(甘肃境内)鱼类作了系统整理,录得鱼类23种,隶属于4目、6科、20属在区系成分上,属西北高原区的7种,占总数的30.4%;江河平原区的11种,占47.8%;北方区的2种,占8.7%:华南区的3种,占13.1%,文章在讨论了渭河上游鱼类区系分析后,并对该地区鱼类资源的开发利用提出了设想和建议。  相似文献   

2.
1987-1990年对广西淡水鱼类单殖吸虫进行了较系统的观察、记录、统计等工作,在所检的79种淡水鱼中,有50多种鱼鳃上寄生有单殖吸虫,共113种,隶属于3科11属。其中4种为新种,6种为特定种。  相似文献   

3.
于2010年9月和11月,对济源太行山猕猴国家级自然保护区的鱼类资源进行了调查.共记录鱼类22种,隶属于5目7科22属.其中,鲤形目17种(以鲤科鱼类为主,14种),鲇形目2种,鳗鲡目、合鳃目和鲈形目各1种.区系分析表明:保护区鱼类含中国平原区系复合体8种,占36.4%;晚第三纪早期区系复合体7种,占31.8%;北方平原区系复合体、北方山地区系复合体和南方平原区系复合体各2种,分别占9.1%;海水复合体鱼类1种,占4.5%.生态类型分析可见,保护区鱼类中静水定居性鱼类9种、溪流定居性鱼类11种、海淡水洄游性鱼类和江湖洄游性鱼类各1种.肉食性鱼类和杂食性鱼类各8种,植食性鱼类和碎屑食性鱼类各3种.  相似文献   

4.
铁布自然保护区的鱼类、两栖类和爬行类   总被引:1,自引:0,他引:1  
1986年至1999年对铁布自然保护区的鱼类、两栖类和爬行类调查结果显示,该保护区有鱼类3科7属10种,两栖类有4科6属6种,爬行类有3科4属4种.对它们的区系组成和生态分布进行了讨论.  相似文献   

5.
舟山海域鱼类名录新考   总被引:2,自引:0,他引:2  
根据2000年4月至2005年4月,作者在舟山各地采集的大量鱼类标本,结合对舟山市各标本馆、所、室等现有舟山鱼类标本的复查,以及核对有关文献资料,确认舟山海域鱼类的种数共为467种,分别隶属于2纲35目158科,其中6种为近年国内外引进种.本文所列出鱼类名录,将为研究舟山海域鱼类形态、分类、生态、物种多样性、鱼类资源保护及合理开发利用提供科学的基础资料.  相似文献   

6.
1986年至1999年对铁布自然保护区的鱼类、两栖类和爬行类调查结果显示,该保护区有鱼类3科7属10种,两栖类有4科6属6种,爬行类有3科4属4种.对它们的区系组成和生态分布进行了讨论.  相似文献   

7.
广东北江鱼类区系研究   总被引:7,自引:0,他引:7  
本文根据1981—1983年的调查结果报告了北江鱼类143种(包括亚种),分隶于11目,26科,93属,其中2个为新种,10个为广东省淡水鱼类新记录.本文详细地研究了北江鱼类的分布、起源、区系组成和北江鱼类区系与其它江河鱼类区系的比较及与毗邻地区鱼类区系的关系,同时对北江鱼类区系在鱼类地理区划上的地位作了分析与讨论.  相似文献   

8.
斗篷山自然保护区鱼类资源初步调查   总被引:3,自引:0,他引:3  
1991年至 1999年间共 4次考察斗篷山区鱼类 ,共采集标本 5 0 0余号 ,鉴定为 32种 ,分别隶属于 4目 9科30属。有 3种鱼类是首次在贵州的长江水系发现 ,即大鳍间吸鳅、越鲶、褐栉虾虎鱼。这 32种占贵州省鱼类总种数的 15 6 %。鲤科鱼类所占比例最大 ,有 18种 ,占斗篷山区鱼类总数的 5 6 2 5 % ;另 14种占 43 75 % ,其中鳅科 3种 ,平鳍鳅科 4种 ,科 2种、科、鲇科、合鳃鱼科、虾虎鱼科、鳢科各一种。该地区鱼类种类资源较丰富 ,但数量却在下降 ,主要原因是采取毒鱼和电鱼等不良捕捞方法导致的  相似文献   

9.
于2008年4月、7月、10月和2009年1月对钱塘江上游昌化溪流域的鱼类物种多样性进行调查.设7个采样点,共获鱼类2949尾,26.826 kg,经鉴定有43种,隶属于4目10科32属.采用多样性指数研究鱼类多样性,结果表明:夏季鱼类多样性指数最高,许联村和首益村的多样性指数较高,并根据优势度指数确定6个优势种;生境类型复杂程度和水温变化,是影响鱼类群落多样性的最主要环境因素.  相似文献   

10.
锡林郭勒高原东半部的乌拉盖盆地,有众多的内陆河流及沼泽、湿地,那里的鱼类,是内蒙古自治区鱼类资源的组成部分之一。在对两次采自该地区的鱼类标本分类鉴定的基础上,概述了该地区的土著鱼类2目3科11属11种,列出了分类检索表。对部分种进行了简略的记述,并提供了一些生态资料。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
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   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
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   

20.
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   

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