空间分布型的形成过程研究

具合影个研究了广义空间分布型和复合空间分布型的形成问题,解释了空间分布型的形成机理,并给出了１１种广义空间分布型和９种复事空间分布型;同时提出了空间分布型的３种判定方法：扩散系数法、空间相关法和参数变动法,它们以可用于区分常见的空间分布型,也可以用于判定分布型的形成过程;为研究空间分布型的形成机理和变化规模提供了有力的手段。以马尾松毛虫的空间分布型的研究结果表明,马尾松毛虫幼虫的空间分布型是复合负     

k-长DNA子序列频数分布研究

在详细阐述了生成DNA序列分形图像的Hao方法后,提出一种能够直观显示k-长DNA子序列频数分布差异性的三维频数分布图生成方法。把3D频数分布图转化为1D对数频谱图,突出显示了频数分布的局部特征,提出k-长DNA子序列频数区划分准则,并详细研究了甚高频数区的n阶零间隔现象,指出n阶零间隔分布就是基因组进化过程所留痕迹的假设,并给出对数频谱图特征的生物学解释。实验发现许多DNA序列频数概率分布近似服从非中心F分布,对于分布呈多峰现象的基因组序列,可采用多个非中心F分布的叠加来拟合。在比较非中心F分布与Gamma分布后,提出一种结合二者在拟合方面具有互补优势的新分布,实验证明这种新分布能够更好地吻合实际DNA序列的频数分布。最后研究了两种特异出现频数(最高出现频数与出现频数为1的k-长子序列个数)与k值的关系,发现不同物种的这两种关系具有良好的一致性。     

Retention function of all segments of IUD usage: a compound distribution.

The distribution of the all segments of IUD use consists of two components: the distribution of the length of each segment and the distribution of the number of segments. In this article, a compound distribution of all segments of IUD, developed by the authors is described. The distribution assumes that each segment of IUD use is a mixed exponential distribution and the number of segments experienced by women is a truncated Poisson distribution. This distribution is useful in estimating the demographic impact of an IUD and IUD program.     

公平视角下护理人员绩效工资分配的改善策略

描述了医疗机构护理人员绩效工资分配办法的现状,在提出基本工资发放存在显性不公平的基础上,进一步揭露了绩效工资分配中的隐性不公平问题,即基本工资较高一方侵占了工资较低一方的部分绩效工资。同时,提出绩效工资分配中隐性不公平程度与护理人员的工资差距和低工资护理人员的数量密切相关。针对传统分配办法的隐性不公平现象,提出了改善绩效工资分配不公平的策略并对改进的效果进行了验证。最后,指出了新型绩效工资分配办法的主要功能主要在于改进公平,而不是提高效率,并应用利益相关者分析方法,对新型分配制度的可行性进行了分析和讨论。     

酵母基因组中ORF数目与长度的关系

根据NCBI数据库中基因注释序列及相关注释文件,统计了酿酒酵母基因组中不同长度的开阅读框架(Open ReadingFrame,ORF)的数目,分析了开阅读框架的数目随长度的分布关系,结果发现有明显的规律性。根据分布的特点用各种分布模型进行拟合比较,提出这类分布是Г(α,β)分布的假设。进一步根据Г(α,β)分布估算了酵母基因组蛋白质编码序列的数目为5870个。该结果对于基因注释具有一定的参考价值。     

Mathematical model of auxin distribution in the plant root

Auxin regulation of plant growth and development is mediated by controlled distribution of this hormone and dose-dependent mechanisms of its action. A mathematical model is proposed, which describes auxin distribution in the cell array along the root longitudinal axis in Arabidopsis thaliana. The model qualitatively simulates auxin distribution over the longitudinal axis in intact roots, changes in this distribution at decreased auxin transport rates, and restoration of the auxin distribution pattern with subsequent establishment of new root meristem in the course of root regeneration after the ablation of its tip. The model shows the presence of different auxin distribution patterns over the longitudinal root axis and suggests possible scenarios for root growth and lateral root formation. Biological interpretation of different regimes of model behavior is presented.     

Optimal nitrogen distribution within a leaf canopy under direct and diffuse light

Nitrogen distribution within a leaf canopy is an important determinant of canopy carbon gain. Previous theoretical studies have predicted that canopy photosynthesis is maximized when the amount of photosynthetic nitrogen is proportionally allocated to the absorbed light. However, most of such studies used a simple Beer's law for light extinction to calculate optimal distribution, and it is not known whether this holds true when direct and diffuse light are considered together. Here, using an analytical solution and model simulations, optimal nitrogen distribution is shown to be very different between models using Beer's law and direct–diffuse light. The presented results demonstrate that optimal nitrogen distribution under direct–diffuse light is steeper than that under diffuse light only. The whole‐canopy carbon gain is considerably increased by optimizing nitrogen distribution compared with that in actual canopies in which nitrogen distribution is not optimized. This suggests that optimization of nitrogen distribution can be an effective target trait for improving plant productivity.     

黑龙江省木本植物区系分析

黑龙江省有木本植物392种,隶属于42科90属。其中裸子植物4科8属34种,双子叶植物37科81属357种,单子叶植物1科1属1种。本省为大兴安岭植物区、东北植物区和蒙古草原植物区三区汇集之地,木本植物地理成分复杂,具有非常明显的温带性质：温带分布科虽然与热带分布科数目相同,但所含种数多,优势明显;温带分布属占75.86%,以北温带分布比例最高;温带分布种占80.43%,以东北分布居首位,其次是中国—日本分布。该区系木本植物起源古老,有珍稀濒危植物9种,特有植物14种及红松、黄檗等孑遗植物,为第三纪植物区系系统。     

Optimality of nitrogen distribution among leaves in plant canopies

The vertical gradient of the leaf nitrogen content in a plant canopy is one of the determinants of vegetation productivity. The ecological significance of the nitrogen distribution in plant canopies has been discussed in relation to its optimality; nitrogen distribution in actual plant canopies is close to but always less steep than the optimal distribution that maximizes canopy photosynthesis. In this paper, I review the optimality of nitrogen distribution within canopies focusing on recent advancements. Although the optimal nitrogen distribution has been believed to be proportional to the light gradient in the canopy, this rule holds only when diffuse light is considered; the optimal distribution is steeper when the direct light is considered. A recent meta-analysis has shown that the nitrogen gradient is similar between herbaceous and tree canopies when it is expressed as the function of the light gradient. Various hypotheses have been proposed to explain why nitrogen distribution is suboptimal. However, hypotheses explain patterns observed in some specific stands but not in others; there seems to be no general hypothesis that can explain the nitrogen distributions under different conditions. Therefore, how the nitrogen distribution in canopies is determined remains open for future studies; its understanding should contribute to the correct prediction and improvement of plant productivity under changing environments.     

中国蜡梅属种质资源的分布及其特点

根据对中国蜡梅属种质资源的调查,结合已有资料,重点阐述了中国蜡梅属植物的地理分布、水平和垂直分布特点及其生境特点。现知中国蜡梅属植物主要分布于我国的13个省,其水平分布很广,很连续,主要分布于秦岭以南、横断山脉以东的广大地区。垂直分布跨度很大,但垂直分布的上下限与经纬度无显著的相关性。蜡梅属植物对水热条件要求较严格,土壤基质多为沙壤土,在群系组成中,蜡梅属植物多为林木层和灌木层的优势成分。蜡梅属植物跨有5个植被类型,主要生长在常绿落叶阔叶混交林和常绿阔叶林地带。     

Sample-Based Vegetation Distribution Information Synthesis

In constructing and visualizing a virtual three-dimensional forest scene, we must first obtain the vegetation distribution, namely, the location of each plant in the forest. Because the forest contains a large number of plants, the distribution of each plant is difficult to obtain from actual measurement methods. Random approaches are used as common solutions to simulate a forest distribution but fail to reflect the specific biological arrangements among types of plants. Observations show that plants in the forest tend to generate particular distribution patterns due to growth competition and specific habitats. This pattern, which represents a local feature in the distribution and occurs repeatedly in the forest, is in line with the “locality” and “static” characteristics in the “texture data”, making it possible to use a sample-based texture synthesis strategy to build the distribution. We propose a vegetation distribution data generation method that uses sample-based vector pattern synthesis. A sample forest stand is obtained first and recorded as a two-dimensional vector-element distribution pattern. Next, the large-scale vegetation distribution pattern is synthesized automatically using the proposed vector pattern synthesis algorithm. The synthesized distribution pattern resembles the sample pattern in the distribution features. The vector pattern synthesis algorithm proposed in this paper adopts a neighborhood comparison technique based on histogram matching, which makes it efficient and easy to implement. Experiments show that the distribution pattern synthesized with this method can sufficiently preserve the features of the sample distribution pattern, making our method meaningful for constructing realistic forest scenes.     

气候变化对6种荒漠植物分布的潜在影响

分析气候变化对植物分布的影响,对保护生物多样性具有重要意义。利用CART（分类和回归树）模型及A2和B2情景,分析了气候变化对短叶假木贼（Anabasis brevifolia）、裸果木（Gymnocarpos przewalskii）、梭梭（Haloxylon ammoden-dron）、膜果麻黄（Ephedra przewalskii）、驼绒藜（Ceratoides latens）和喀什膜果麻黄（Ephedra przewalskii var.kaschgarica）分布范围及空间格局的影响。结果表明：气候变化下,这些植物目前适宜分布范围减小;从新适宜及总适宜分布范围而言,短叶假木贼和梭梭从1991-2020年到2051-2080年时段增加,之后减小,其它植物从1991-2020年到2081-2100年时段减小;喀什膜果麻黄和驼绒藜适宜分布范围减小并破碎化,其它植物向目前适宜分布的西部、西北部（或青海西南部）、昆仑山、阿尔金山和祁连山区扩展;除驼绒藜和喀什膜果麻黄与年均气温变化具显著相关性外,其它植物分布范围与年均气温和降水量变化的相关性较弱（P〉0.05）,除驼绒藜、喀什膜果麻黄和裸果木目前分布范围与年均气温和降水量变化的回归关系较强外,其它植物分布范围与年均气温和年降水量变化多元线性回归关系较弱。上述研究结果表明,气候变化下,这些植物空间分布格局改变,目前分布范围减少,新适宜及总适宜分布范围近期增加,随着气候变化程度的增强,又逐渐减小。     

GEOGRAPHIC DISTRIBUTION AND POTENTIAL DISTRIBUTION ESTIMATION OF PSEUDOTAXUS CHIENII

 利用Diva-Gis软件对东亚特有单种属植物白豆杉(Pseudotaxus chienii)的地理分布格局进行研究。结合海拔图层和植被图层绘制白豆杉的分布图, 并用Diva-Gis中整合的Bioclim和Domain两个生态模型估测了白豆杉的潜在分布区。结果表明, 白豆杉分布在长江以南地区中低海拔450~1 500 m山区山坡林下、沟谷地带及溪边灌丛中, 浙江地区为白豆杉分布最为密集的地区。白豆杉的分布与植被类型和海拔有着密切的关系, 分布区的植被类型为常绿灌木林、阔叶林及常绿针阔叶混交林; 由东到西, 分布的最低海拔升高, 海拔范围缩小, 白豆杉资源量减少。白豆杉潜在分布区为浙、闽、粤、赣、湘、桂及黔几省及其交界处, 从浙江南部山区沿武夷山山系至南岭山系(向北到湘赣交界的罗宵山系甚至可以延伸到大别山系)至大瑶山山系(向北沿雪峰山)。保护方式应以就地保护为主, 同时兼顾其未来潜在的分布区, 关键是对白豆杉的适生区生境的保护。     

Heterogeneity of resource utilization in a population of the Australian reptile tick, Aponomma hydrosauri (Denny)

Abstract. 1. The distribution of adult males, nymphs and larvae of the reptile tick Aponoma hydrosauri on their host, Trachydosaurus rugosus , in a study area near Tickera, South Australia, did not follow the Poisson distribution predicted if hosts were infested at random.
2. The non-random distribution of males can be accounted for by geographical heterogeneity in distribution. Adult females also showed geographical heterogeneity in their distribution pattern, but infested their hosts at random over all.
3. Larvae and nymphs show distribution patterns which change both with the time and the locality. However, when these biases are removed the distribution of larvae and nymphs on their hosts is still non-random.
4. Larger lizards tend to have larger numbers of ticks, but this cannot alone account for the clumped distribution.
5. A model is proposed relating the tick distribution pattern to the particular problems of a resource which is hard to find, but plentiful once found.     

On the Discrete POISSON-Inverse GAUSSian Distribution

The discrete POISSON-inverse GAUssian distribution is obtained by compounding the POISSON distribution with the inverse-GAUssian distribution. The maximum likelihood of the parameter is discussed. Comparison with the POISSON, negative binomial, POISSON-LINDLEY and the generalized WARING distribution when fitting a distribution to accident statistics data is given.     

秦岭种子植物区系科的组成、特点及其地理成分研究

秦岭种子植物区系组成丰富, 共有种子植物198 科、1007 属、3446 种, 区系组成的大科及主要科共16 科, 占秦岭种子植物总数属的50.05%, 总种数的57.25%, 它们构成了秦岭植物区系组成的基本框架, 就其性质来讲, 绝大多数为温带性质。松科、壳斗科、桦木科、杨柳科、蔷薇科、杜鹃花科、禾本科、莎草科等是秦岭植被的区系组成的优势科, 从地理成分上来分析, 本区科的分布型可以划分为世界或亚世界分布科、热带分布科、温带分布科、间断分布科以及东亚和中国特有科, 其区系的起源则有明显的古老性。     

Distribution patterns of some subterranean Crustacea in the territory of the former Yugoslavia

A selection of the most representative distribution patterns of stygobiont animals is presented. The range of a genus may extend beyond the Dinaride karst, while some species exhibit a holo-Dinaric distribution. The mero-Dinaric distribution is organised in two vicarious centres (in the NW and SE) as well as an epilittoral and a paralittoral belt. The paralittoral distribution is a result of paleogeographic rather than present-day ecological conditions. Important differences between the interstitial faunas of Slovenia (and NE Italy) and Macedonia are probably the result of their different sources. Some other distribution patterns are discussed or summarized from the existing literature. The distribution patterns of this stygobiont fauna are extremely diverse, and are influenced by the geological complexity of the territory as well as by the richness of the fauna concerned. New distribution data for some Copepoda, Thermosbaenacea, and Amphipoda are appended.     

A Suprasystem of Probability Distributions

A set of differential equations is described whose solutions represent a general system of probability distribution functions. Previously reported systems of such distribution functions are special cases of this general system. The differential equations can be used to represent distribution functions and generate their related statistics in cases for which no simple formula for the distribution is known. The generality of this suprasystem of distribution functions and its potential utility are discussed.     

甘薯象空间格局及抽样技术研究

通过空间分布型指数分析,甘薯象对薯块、著株危害空间分布型为随机分布或均匀分布;同时确定了理论抽样数     

GIS在野生动物空间分布格局研究中的应用

地理信息系统(GIS)在绘制动物分布图、确定物种丰富度、预测动物的空间分布格局、建立物种分布数据库等方面都有极大的应用价值。本文介绍了GIS技术在野生动物空间分布格局研究中的应用,并探讨了今后GIS技术在野生动物生态学领域的应用前景。