空青山次生阔叶林群落类型及物种多样性研究

空青山次生阔叶林可划分为两个植被类型;落叶阔叶林和落叶－常绿阔叶混交林;６个群系;栓皮栎林,麻栎林,白栎林,黄连木白蜡树－白花龙林,栓皮栎－冬青林,白栎－冬青林,８个群丛。由于人为干扰较大,常绿成分残存较少,外貌上近似落叶阔叶林。笔者对各个群丛的结构特征进行了研究并加以描述。对群落物种多样笥的研究结果表明,物种多样性指数表现为满足木层－草本层－乔木层;不同群落类型不同层次的物种多样性的大小与立地条     

贵州省务川县鹿坪乡和牛塘乡古森林残存群落中的银杏

本文系“贵州省古森林残存群落”系列调查之二。着重对务川县鹿坪村白果园及务川县丰乐镇大院子川王庙两处古森林残存群落中的银杏种群进行了定量研究,相应介绍了森林群落的结构、成分、数量及立木的物侯型级。根据现有资料证明：两处森林仍具有常绿阔叶林的典型的群落特征。白果园森林群落应属“针阔叶混交的古森林残存群落”;川王庙森林群落则属于“常绿与落叶阔叶混交的古森林残存群落”。在上述群落中,银杏种群同森林中其它种     

王二包自然保护区森林植被的数量分类

以森林植被样地中乔木层树种的重要值为指标,采用纸条排队法、群落相似系数分类法、最近邻体法、组平均法对王二包自然保护区森林植被样地进行数量分类．结果表明：①4种分类结果基本相似,所调查的15个样地分为4个植被型8个群系;②区内常绿阔叶林类型基本处于稳定的顶极阶段,仅有少数样地受到人为干扰,群落表现出次生性质,如加强管理,群落将会恢复其原生稳定状态．     

鄂西狮子关电站库区主要森林植被类型的数量分类

在对鄂西狮子关电站库区森林的群落样方调查的基础上,研究其森林典型植物群系的特点及演替动态,并结合数量分类,将该地区主要森林植被类型－常绿阔叶林和针阔混北林划分为13个群系。     

天门山地理成分与植被类型分析研究

通过对天门山的地理成分和植被类型进行分析,统计植物区系,研究天门山科、属的结构组成。将天门山划分为山顶矮阔叶林、落叶阔叶林、常绿落叶阔叶混交林、常绿阔叶林、暖性针阔叶混交林五个植被类型,分别对主要植被类型的群落外貌、结构及物种多样性进行调查研究,为天门山的植被及植被保护工作提供科学依据。从生活型、叶的性质和季相出发对天门山植被类型进行比较,分析群落优势种重要值、垂直结构和径级结构以及不同径级和高度级物种多样性,进一步明确了天门山的空间排列和群落演替趋势,为更好地开发利用天门山植物资源提供帮助。     

大别山植物区系的特点和森林植被的研究

大别山植物种类丰富，古老，孑遗植物较多，植物区系地理成分复杂、联系广泛、特有现象明显。森林植被的主要类型有：常绿阔叶林，常绿落叶混交林，落叶阔叶林，山地矮林和针叶林。本文对大别山森林植被现状进行了生态评价，并对其合理开发利用提出了一系列建议。     

浙江省珊溪水库库区森林植被类型的研究

珊溪库区森林植被类型主要有：中亚热带常绿阔叶林、中亚热带常绿-落叶阔叶混交林、中亚热带落叶阉叶林、中亚热带针叶林、中亚热带针阔混交林、竹林、灌丛和灌草丛。其中,中亚热带常绿阔叶林为地带性森林植被类型。     

海南岛三指山与台湾岛南仁山森林比较研究

比较研究了海南岛五指山自然保护区与台湾岛南仁山垦丁森林公园的植物区系成分，森林结构，森林类型和群落特征。结果表明，海南岛五指山森林是中国热带雨林植被的一个重要组成部分，而台湾岛南仁山森林则是中国南亚热带常绿阔叶林的代表类型之一。     

粤西黑石顶自然保护区杉木林与次生常绿阔叶林群落特征比较

研究了粤西黑石顶相近年龄的杉木(Cunninghamia lanceolata)林与次生性常绿阔叶林的物种多样性及群落结构特征，并与中生性常绿阔叶林进行比较．结果表明，杉木人工林在16龄及24龄时物种多样性水平均较低，而次生性常绿阔叶林在演替过程中物种数目迅速增加并超过中生性常绿阔叶林，物种多样性在16龄及26龄时均达到较高水平．杉木林在16龄至24龄期间群落密度变化不大，始终稍低于中生性常绿阔叶林，群落始终以杉木占据优势，生物量与基面积逐渐积累增加．次生林在演替初期，群落密度远高于中生性常绿阔叶林，但随演替的进程而逐渐下降并趋于稳定，在16龄到26龄的10a间优势种的组成发生很大变化，而生物量与基面积增加很少，群落演替发生迟滞．在生物量分配方面，次生林地下生物量所占比例最高，杉木林最低，中生性常绿阔叶林居于两者之间。     

祁门县查湾两种主要植被类型的初步研究

通过群落外貌、结构、种类成分、重要值、动态与演替等特征，分别对查湾两种主要植被类型常绿阔叶林和常绿－落叶阔叶混交林进行初步分析．地带性常绿阔叶林主要是甜储林；非地带性常绿－落叶阔叶混交林种类丰富，结构复杂，藤本植物粗壮、高大．     

An Index mechanism for multi-scale view in spatial databases

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

A computer generator for randomly layered structures

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

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

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     

Advances in broadband wireless communications under high-mobility scenarios

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.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

Scale-based spatial data model for GIS

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.     

Exciton Seebeck in Molecular Systems

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     

Achieving Unusual States of Matter Under High Pressure

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