生物多样性熵值测度指标的应用与分析

以一般生物多样性指标为基础．对熵值测度指标进行了研究,用熵值及其他多样性指标分析评价了新疆克拉玛依荒漠植被的生物多样性。结果表明,熵值测度指标与一般生物多样性指标在机理上有对应性,不仅可作为物种多样性、生态优势度、物种丰富度的优良评价指标,而且可以说明系统的物种对系统的贡献大小及其演化方向。     

食物网与物种多样性和系统稳定性研究

围绕生物多样性主要问题——物种多样性和系统稳定性之间的关系从食物网的角度究，（1）生物多样性与系统稳定性之间的关系：本世纪70年代以前，生态学家普遍认为，生态系统的稳定性随生物多样性的增加而提高；自70年代后期一些理论学家普遍向这一看法提出挑战以来，在这一问题上出现了两大阵营；（2）生物多样性——稳定性和食物网的关系：从食物网的角度综述了近半个世纪来生物多样性对系统稳定性的影响的研究结果，随着两大阵营的出现，食物网理论也从当初的营养级越多系统越稳定的观点转变为食物网随着食物链复杂性的增加而降低，但仍有许多科学家坚持以往的观点；（3）生物多样性——稳定性关系和物种作用强度的关系：把食物网量化后提出了物种阃的相互作用强度的概念，研究发现一个生态系统是由这些强相互作用决定的，而大部分的弱相互作用对一个生态系统的稳定起影响作用；弱相互作用对系统的影响程度具有时空特异性。     

食物网与物种多样性和系统稳定性研究

围绕生物多样性主要问题——物种多样性和系统稳定性之间的关系从食物网的角度究,(1)生物多样性与系统稳定性之间的关系:本世纪70年代以前,生态学家普遍认为,生态系统的稳定性随生物多样性的增加而提高;自70年代后期一些理论学家普遍向这一看法提出挑战以来,在这一问题上出现了两大阵营;(2)生物多样性——稳定性和食物网的关系:从食物网的角度综述了近半个世纪来生物多样性对系统稳定性的影响的研究结果,随着两大阵营的出现,食物网理论也从当初的营养级越多系统越稳定的观点转变为食物网随着食物链复杂性的增加而降低,但仍有许多科学家坚持以往的观点;(3)生物多样性——稳定性关系和物种作用强度的关系:把食物网量化后提出了物种间的相互作用强度的概念,研究发现一个生态系统是由这些强相互作用决定的,而大部分的弱相互作用对一个生态系统的稳定起影响作用;弱相互作用对系统的影响程度具有时空特异性。     

食物网与物种多样性和系统稳定性研究

围绕生物多样性主要问题--物种多样性和系统稳定性之间的关系从食物网的角度究,(1)生物多样性与系统稳定性之间的关系本世纪70年代以前,生态学家普遍认为,生态系统的稳定性随生物多样性的增加而提高;自70年代后期一些理论学家普遍向这一看法提出挑战以来,在这一问题上出现了两大阵营;(2)生物多样性--稳定性和食物网的关系从食物网的角度综述了近半个世纪来生物多样性对系统稳定性的影响的研究结果,随着两大阵营的出现,食物网理论也从当初的营养级越多系统越稳定的观点转变为食物网随着食物链复杂性的增加而降低,但仍有许多科学家坚持以往的观点;(3)生物多样性--稳定性关系和物种作用强度的关系把食物网量化后提出了物种间的相互作用强度的概念,研究发现一个生态系统是由这些强相互作用决定的,而大部分的弱相互作用对一个生态系统的稳定起影响作用;弱相互作用对系统的影响程度具有时空特异性.     

天目山自然保护区生物多样性的熵值测度研究

说明了生态系统是典型的热力学开放系统,并具有耗散结构的特征,阐述了生物多样性的热力学熵机理.在此基础上提出了生物多样性的两个熵值测度指标,并分析了各指标的含义、两指标间的相互关系及其与传统测度指标机理上的对应性.用天目山自然保护区典型样地调查数据进行了验证,验证结果与生物多样性的熵值分析机理相一致.通过对比分析,笔者认为传统生物多样性测度指标没有考虑群落中各种群在个体数量上的绝对差异对生物多样性的影响,从而提出了生物多样性的熵值改进方法,并分析了与熵值测度指标密切相关的几个关键性问题及影响天目山群落生物多样性的主要原因.     

物种多样性与干扰

随着近年来温室效应、环境污染、世界性缺水的加剧,荒漠化、沙尘暴、洪水、干旱、疾病的肆虐,可耕地、环境的退化,濒危物种的增多,生态系统的破坏及生物多样性的丧失等等,环保、生态系统的恢复与重建、生物多样性的保护日益成为人们关注的焦点。生物多样性不仅为人类提供了食品、医药保健及多种多样的工业原料,而且在调节气候、涵养水源、保护土壤、固定能量、促进生物能源循环等生态系统功能方面的作用,是任何活动都无法替代的。物种丰富的植物群落为生物多样性及日益减少的资源撑起了储存的仓库(Jonathan Silvertown等,1999)。生物多样性是生物及其环境形成的生态复合体及与其相关的各种生态过程的总和,它包括物种多样性、基因多样性、生态系统多样性(孙儒泳),近年来又提出了景观多样性。就生物多样性及其与干扰的关系进行初步探讨。     

生态系统的可靠性及其稳定性的维持

 生态系统的营养结构是由营养级组成的.可靠性模型实验表明,营养级的可靠性取决于物种的失效率大小,物种丢失对物种丰富、失效率高的营养级的可靠性影响甚微,而对物种贫乏、失效率低的营养级略大,换言之,营养级的可靠性与物种的丰富度无紧密关系.其次,在营养级可靠性相同的条件下,简单系统的可靠性普遍略高于营养级多或食物链长的复杂生态系统.生物多样性与生态系统的稳定性没有必然联系,只要营养级还存在(无论剩下几个物种),那么按串并联方式组合成的生态系统就不会崩溃.生态系统的稳定性是冗余结构的稳定性.生态系统经常遭受干扰,但物种和个体的丢失可以通过来自其内外源源不断的冗余补充,以维持生态系统营养结构的稳定性.     

CONSERVATION OF BIODIVERSITIY AND SUSTAINABLE DEVELOPMENT IN CHINA

生物多样性是生命系统的基本特征,也是生物有机体及其与环境之间复合而成的生态系统和各种有关生态过程的总和.生物多样性主要包括三个层次基因多样性、物种多样性，生态系统多样性.中国的幅员辽阔,生境复杂,气候多变,历史悠久,拥有丰富的植物、动物和微生物种类及不同的生态系统类型.多年来,我国采取了一系列措施和行动,旨在保护生物多样性,促进国家经济、人类社会和自然生态系统的持续发展.     

保护生态环境对于生物多样性的重要意义

生物多样性是指一定范围内多种多样活的有机体（动物、植物、微生物）有规律地结合所构成稳定的生态综合体。这种多样包括动物、植物、微生物的物种多样性,物种的遗传与变异的多样性及生态系统的多样性。生物多样性是生物及其与环境形成的生态复合体以及与此相关的各种生态过程的总和,包括数以百万计的动物、植物、微生物和它们所拥有的基因以及它们与其生存环境形成的复杂的生态系统,是生命系统的基本特征。     

保护生物多样性的措施

生物多样性的含义,包括植物、动物、微生物的所有物种和物种所在生境的生态系统及其生态系统中的生态过程.生物多样性通常被认为有三个水平,即遗传多样性、物种多样性和生态系统多样性.遗传多样性即基因多样性,是遗传信息的总和,存在于植物、动物和微生物个体的基因内;物种多样性是指动、植物及微生物种类的丰富程度;而生态系统多样性是指生物圈中的生境、生物群落和生态过程差异的多样化.因此,保护生物多样性就是在基因、物种和生态系统三个水平上采取保护措施和保护战略.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

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

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-