优势种

In buffer zone, there were 14 invasive alien plant species out of 62 investigated plant species, accounted for 22.58%t of total plant species. The comprehensive values of dominance of Pliea microphylla, Ageratum conyzoides and Wedelia trilobata were larger than that of other plant species.

在缓冲区样方内共调查到62种杂草，其中外来入侵植物14种，占植物总数的22.58%，外来入侵植物小叶冷水花、胜红蓟和三裂蟛蜞菊Wedelia trilobata的优势度综合值最大。

There were only three invasive alien plant species out of 24 investigated plant species occurred in core zone, which were clearly lower than those of experimental and buffer zones. The invasive alien plant species accounted for 12.5% of total plant species. The invasive alien plant species with the largest comprehensive values of dominance were Peperomia pellucida and Ageratum conyzoides.

在核心区的样方内共调查到了24种植物，外来入侵植物有3种，占植物总数的12.50%，入侵植物数量明显低于实验区和缓冲区，优势度综合值最大的外来入侵植物是草胡椒Peperomia pellucida和胜红蓟。

Benthic species have been identified, among which Mollusca and Arthropoda are dominant socials. As a fauna nature, the eurythermous-eurytopic species and the subtropical species predomi-nate absolutely over the others.

初步鉴定，物种共有97种，以软体动物和节肢动物占优势，同时，生态类群以我国沿海广温广布性种和亚热带种占绝对优势。

1Niche construction can lead to stable coexistence of diverse genotypes in spatially structured population, which supports a stable polymorphism even without heterozygote superiority.(2)With habitat deterioration, niche construction accelerates the formation of steady polymorphism and hence impedes the harmful influences of environment on the population, which might embody a life-history strategy of organism under the unfavorable environment.(3)Niche construction results in the coexistence with alternative polymorphism through genotype-environment feedback and limited gene flow.(4)The niche-constructing organism is an active force to alter its environment and hence the direction of natural selection in order to better survival.(5)Spatial dynamics and distribution pattern of metapopulation are profoundly influenced by time-lagged niche construction.(6)Metapopulation size can reach a fixed level in the recency effect and equal weighting of time lag but is statistical stability in primacy effect, which implies the primacy effect is most remarkable.(7)The increment in the relative weightingof each generation\' niche construction and the length of time lag are significant factors for system destabilization.(8)Moderate capacity of positive niche construction benefits the metapopulation persistence.(9)The narrowing of niche breadth can decrease the metapopulation size and thereby increase the extinction risk.(10)The coupled function of time lag and niche construction make the system oscillation and generate the spiral wave, spiral-broken and circular wave in heterogeneous habitat.The spatial distributions of metapopulation and resource content are complementary due to a phase lag of their both frequencies.(12)Metapopulation persistence with niche construction depends not only on the balance between colonization and extinction, but also on the balance between the ability of niche construction and natural dissipation of habitat.(13)Metapopula-tion can survive under certain condition when the percent of suitable patches in habitat is lower than the ration of extinction to colonization.(14)Two thresholds exist in the process of transition of habitat quality dynamics from unsuitable to suitable, which include the intensity of niche construction and the initial condition of system.(15)Metapopulation size is positive correlated with the ability of positive niche construction, which means that organism or population who has strongly positive influences on their environment plays an important role to maintain the available habitat.

通过上述几个方面的研究，主要得出以下15条结论：(1)生态位构建可使空间结构种群，甚至是在没有杂合子优势的条件下，形成多种可能的稳定基因型分布模式；(2)随着环境的破坏与恶化，种群的生态位构建作用加速其较早形成稳定多态以阻碍环境对种群的不利影响，解释了有机体在不利环境下的一种生活史对策；(3)生态位构建作用通过基因型—环境反馈机制及有限的基因交流导致基因型多态的稳定共存；(4)有机体的生态位构建作用是一种积极的动力改变环境进而改变其自然选择的方向；(5)生态位构建的时滞作用对集合种群动态和空间分布产生深刻影响；(6)集合种群大小在时滞的崭新效应和等权重效应下达到一固定值，而在首位效应下达到统计稳定，表明首位效应的影响最显著；(7)首位效应下生态位构建相对权重的增量和时滞的长度是影响系统不稳定性动态的关键因素；(8)适中的生态位构建强度有利于集合种群的续存；(9)生态位宽度变窄会减少集合种群的数量从而增加其灭绝风险；(10)时滞和生态位构建的双重作用使系统产生周期振荡，并在异质性环境中产生稳定的螺旋波，破碎的螺旋波和环形波三种分布模式；(11)集合种群与资源含量的空间分布因为相滞而互补；(12)具有生态位构建的集合种群续存不仅取决于侵占率与灭绝率之间的平衡，而且依赖于生态位构建能力同其生境的自然消耗速率之间的妥协；(13)当生境中适合侵占的斑块比例小于其侵占率与灭绝率之比时，生态位构建作用促使集合种群在一定条件下续存：(14)生境斑块的状态从不适合到适合转变过程中存在生态位构建强度和系统初始条件这两个阈值；(15)集合种群的大小同正生态位构建能力正相关，意味着对环境具有较强正作用的有机体对维持有效生境起积极作用。

In history and reality, the contradiction between needs and limited resource always exists. From the view point of system-science, it can be concluded that:①The interaction among need-contradiction-ability is the perpetual force for enterprise evolution (and the evolution of other living systems). The improvement of "ability"is the process and result of evolution.②The competition and coordination among systems is the direct power for enterprise evolution. Competition produces various system actions. Coordination makes systems complement their functions with each other. The interactions of competition and coordination push enterprise into the flow of evolution and optimization.③The"stochastic fluctuation"of the system, which is accidental finding, is another force for enterprise evolution. It is a deterministic element in the process of the self-organization of enterprise.

在历史和现实中，需要和满足需要资源稀缺之间的"问题"是恒久存在的，从系统科学的角度可以演绎出：①需要一问题一能力三种异质要素的相互作用是企业进化（其它一切有生命系统进化）的永恒动力，"能力"的提高正是进化的过程和结果；②各系统间的竞争与协同是企业进化的直接动力，竞争产生多样化的系统行为，协同则使各系统间优势互补，竞争与协同交互作用推动企业呈现出进化与优化的趋势：③系统的"随机涨落力"即意料之外的发现与创新是推动企业进化的又一种动力，它是企业自组织过程中带有必然性的力量：④在解决"问题"中创新者的作用不可低估，但更为根本地说创新者只是"需要一问题一能力"这三种要素相互作用的载体，个体的创新是企业自组织过程的必然结果。

Chain-grate bed temperature field is a large inertial, nonlinear and time delays controlled system.Its math model is not easy to figure out.Three Fuzzy-PID controllers are presented in this paper based on the dynamic character of fuzzy control and the static character of PID control.They are simulated via combining fuzzy logic toolbox with Simulink.The simulation result shows that they have better characters both in dynamic and static than general PID controller.At the same time, they have better robustness...

链篦机篦床温度场是大惯量、非线性、纯滞后的系统，其数学模型具有较大的不确定性；为实现其精确控制，结合模糊控制和PID控制各自在动态响应和稳态精度上的优势，提出了三种模糊PID控制器；利用Matlab的模糊工具箱和Simulink对三种控制器和常规PID控制进行了仿真比较；仿真结果表明，三种模糊PID控制器与常规PID控制相比具有良好的控制品质和较好的适应性。

First this paper analyzes and clarifies the statistical investigating data of winter migrant birds in Poyang lake in many years, and selects 44 samples on behalf of the main lake, this paper analyzes the birds community characteristic of abundant, variety, even, dominant and the meeting rate among the plant; this paper selects 10 environmental elements according to the reality of Poyang lake and selects the characteristic bird among rare plant, normal plant, wading bird, swimming bird etc, and.

本文首先通过对环鄱阳湖地区越冬候鸟多年调查统计数据的梳理和分析，筛选44个具有代表性主要湖泊作为样本，分析了各湖候鸟群落的丰富度、多样性、均匀性、优势度和种间相遇机率等特征；根据鄱阳湖实际选取10个环境因子，从稀有种、常见种、涉禽、游禽等方面结合选择具有代表性候鸟，进行了候鸟与湿地环境因子的相关关系分析。

There are 73 families, 139 genera and 179 species distributed in 0 1 ha of different land Use Stages of Daka and 70 families 146 genera and 166 species distributed in 0 08 ha different land use stages of Baka, Xishuangbanna.

与热带雨林相比较，广布种由 1 0 %分别上升为 2 0 %，而且排位由第 9位分别上升到第 3位和第 3位，表明热带山地不同土地利用阶段造成植物区系成份中热带种和亚热带种优势减小。

This review discusses the international development status of biodiesel fuels in terms of 5 potential oil plants (Jatropha curcas, Cornus wilsoniana, Xanthoceras sorbifolia, Pistacia chinensis and Cerasus humilis) and 1 wild oil plant species mainly introduced according to the situation in China. The advantage of improving the content of oil plants by transgenic technology is discussed, and 4 techniques of biodiesel fuel production are summarized.

本文介绍了极具潜力的5种木本油料植物麻疯树、光皮树、文冠果、黄连木和欧李和1种野生草本油料植物海篷子，进而提出运用转基因技术提高燃料油植物种子含油量的优势，归纳总结了生产生物柴油的4种不同工艺。

In this region, there are 204 kindsof wild fruit plants that belong to 57 families and 101 genera are recorded,Occuping the 73 families and 173 genera and 1157 kindsof national wild fruit plants is 78.1%,58.4%,17.7%.4 families including Rosaceae,Fagaceae,Rutaceae and Moraceae are dominant ones,each of them has more than 15 species growing there.

摘 要 本文报道了粤东地区野生水果植物资源的调查结果，记录到该地区野生水果植物有57科、101属、205种，分别占全国野生果树73科、173属、1157种的78.1%、58.4%、17.7%，含15种以上的科有蔷薇科、壳斗科、芸香科、桑科4个科，为本地区野生水果的优势科。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。