如何建立利用翅脉鉴定卷蛾种类的专家系统(英文)

作者已经报导了利用卷蛾翅脉作为种类鉴定的可行性。本文具体介绍用翅脉鉴定种类的专家系统里的三个关键性技术要点。它们是:在翅脉交点坐标系确立问题上,创立了“二中心法”;在翅脉图像输入时,发明了“模型对位法”;最后,在输出鉴定结果时,又提出了“类似度排序法”。     

利用翅脉图像计测对卷蛾亚科(鳞翅目)鉴定的专家系统(英)

本研究分析了卷蛾亚科Torticinae(Lepidoptera)53个种前翅翅脉电脑录像,确立了一套利用翅脉图像计测来鉴定卷蛾种类的方法,并开发了一个对应的专家系统。这个方法首先测定卷蛾翅脉上的22个交点(vein point)的坐标,然后把这些坐标值做为鉴定的特征依据输入数据库。 当拿到要鉴定的标本时,先让电脑自动测定其各翅脉交点坐标,再求出它与数据库中的53个种的交点坐标的相异度(dissimilarity),最后在屏幕上显示出它与53个已知种的相异度名次,相异度越小,则说明彼此翅脉越相似,与要鉴定的标本是同种的可能性越大。模拟实验的结果,名列第一的准确率高达98.2％,名列第二、第三的准确率为1.8％。 为了保证100％的准确率,本系统还将这53个已知种的成虫形态图、雌雄外生殖器解剖图、以及形态文字描述、生活习性、分布、寄主等也输入本系统。这些资料可以随时提取、配合鉴定。这一专家系统不受语言和专业程度限制,既简单迅速又准确,不失为鉴定卷蛾种类的一个好的新方法。     

A Novel Method of Automatic Plant Species Identification Using Sparse Representation of Leaf Tooth Features

Automatic species identification has many advantages over traditional species identification. Currently, most plant automatic identification methods focus on the features of leaf shape, venation and texture, which are promising for the identification of some plant species. However, leaf tooth, a feature commonly used in traditional species identification, is ignored. In this paper, a novel automatic species identification method using sparse representation of leaf tooth features is proposed. In this method, image corners are detected first, and the abnormal image corner is removed by the PauTa criteria. Next, the top and bottom leaf tooth edges are discriminated to effectively correspond to the extracted image corners; then, four leaf tooth features (Leaf-num, Leaf-rate, Leaf-sharpness and Leaf-obliqueness) are extracted and concatenated into a feature vector. Finally, a sparse representation-based classifier is used to identify a plant species sample. Tests on a real-world leaf image dataset show that our proposed method is feasible for species identification.     

Approaches to the identification of angiosperm leaf remains

During the past 125 years the history of early angiosperms, interpreted through the fossil leaf record has been largely an exercise in paleofloristic studies, ignoring evolution. Imprecise identifications of ancient leaves “matched” to extant genera and families have been used as the basis for reconstructions of paleocommunities and paleoclimates. However, as the result of careful morphological studies of leaf form, venation and cuticular features new insights into the evolution of angiosperms are now available. In this paper considerations are given to the usefulness and shortcomings of leaf form, venation and cuticular analysis as diagnostic tools of plant identification. Many techniques for the study of the morphology of modern and fossil leaves are included in this paper as well as tables outlining features of leaf venation and the epidermis. Careful morphological studies of leaf form (such as the venation and epidermal characters emphasized in this paper) will provide better understanding of the relationships of living angiosperms and transform the fossil leaf record into useful data that can be used to study the evolution of the angiosperms.     

An efficient method for estimating vein density of Glossopteris and its application

Glossopteris-type leaves are the most abundant floristic element from the Gondwanan continent and are recorded throughout the Permian, which was a period of extreme icehouse-to-hothouse climatic global change. Fossil leaf traits can be useful for the reconstruction of palaeoenvironments and identification of climatic changes throughout geological time, but the conservative morphology of Glossopteris leaves has thus far made them difficult to use for this purpose. If the characters of Glossopteris can be better quantified then it should make them useful for tracking environmental changes over a wide geographical area and over a long time interval. Venation density is a highly variable leaf trait that might be useful for this purpose. This trait can be calculated, usually as vein length per centimetre squared, but this can be a time-consuming procedure. In this paper we propose a new rapid method to estimate venation density in a conical sector of Glossopteris leaf lamina using an accurate linear model whose predictors are three linear venation densities, measured as veins per centimetre. In addition to substantially reducing the data collection time, it is less biased and more reproducible than methods applied previously with this leaf type. Using this more robust method, preliminary results significantly distinguish the venation densities of leaves produced in wet and drier ecosystems, matching a pattern similar to modern plants. This is the first survey using a large sample size to reveal that environmental stress controlled the vein architecture of Palaeozoic plants, in a manner similar to plants in modern ecosystems.     

基于人工神经网络的叶脉信息提取--植物活体机器识别研究I

叶片的识别是识别植物的重要组成部分,特别在野外识别植物活体尤其重要.叶脉的脉序是植物的内在特征,包含有重要的遗传信息.但由于叶脉本身的多样性,利用单一特征的图像处理方法难以有效地提取叶脉.为了充分利用图像的信息,本文提出了一种基于人工神经网络的叶脉提取方法.该方法利用边缘梯度、局部对比度和邻域统计特征等10个参数来描述像素的邻域特征,并将其作为神经网络的输入层.实验结果表明,与传统方法相比,经过训练的神经网络能够更准确地提取叶脉图像,为进一步的叶片识别打下了良好的基础.     

基于人工神经网络的叶脉信息提取——植物活体机器识别研究Ⅰ

叶片的识别是识别植物的重要组成部分,特别在野外识别植物活体尤其重要。叶脉的脉序是植物的内在特征,包含有重要的遗传信息。但由于叶脉本身的多样性,利用单一特征的图像处理方法难以有效地提取叶脉。为了充分利用图像的信息,本文提出了一种基于人工神经网络的叶脉提取方法。该方法利用边缘梯度、局部对比度和邻域统计特征等10个参数来描述像素的邻域特征,并将其作为神经网络的输入层。实验结果表明,与传统方法相比,经过训练的神经网络能够更准确地提取叶脉图像,为进一步的叶片识别打下了良好的基础。     

基于二叉分类推理的昆虫分类辅助鉴定多媒体专家系统通用平台TaxoKeys的设计与开发

本文详细介绍了基于二叉式分类推理的昆虫分类辅助鉴定多媒体专家系统通用平台TaxoKeys的设计与开发,及其所具备的主要特点。该研究根据昆虫分类学的特点,将昆虫分类的两项式检索表用数据库表示成系统知识库,利用计算机数据结构中二叉树结构的分枝结点搜索技术来实现其推理过程,进行昆虫分类的辅助鉴定,为昆虫分类专家提供一个通用专家系统平台。该系统具有可扩充性好、设计简单、操作方便等特点,同时也适用于一般性生物分类鉴定。另外,本文还就本系统功能的进一步扩展与应用研究等进行了探讨。     

Evolution and Function of Leaf Venation Architecture: A Review

The leaves of extant terrestrial plants show highly diverseand elaborate patterns of leaf venation. One fundamental featureof many leaf venation patterns, especially in the case of angiospermleaves, is the presence of anastomoses. Anastomosing veins distinguisha network topologically from a simple dendritic (tree-like)pattern which represents the primitive venation architecture.The high degree of interspecific variation of entire venationpatterns as well as phenotypic plasticity of some venation properties,such as venation density, indicate the high selective pressureacting on this branching system. Few investigations deal withfunctional properties of the leaf venation system. The interrelationshipsbetween topological or geometric properties of the various leafvenation patterns and functional aspects are far from beingwell understood. In this review we summarize current knowledgeof interrelationships between the form and function of leafvenation and the evolution of leaf venation patterns. Sincethe functional aspects of architectural features of differentleaf venation patterns are considered, the review also refersto the topic of individual and intraspecific variation. Onebasic function of leaf venation is represented by its contributionto the mechanical behaviour of a leaf. Venation geometry anddensity influences mechanical stability and may affect, forexample, susceptibility to herbivory. Transport of water andcarbohydrates is the other basic function of this system andthe transport properties are also influenced by the venationarchitecture. These various functional aspects can be interpretedin an ecophysiological context. Copyright 2001 Annals of BotanyCompany Review, leaves, leaf venation, evolution, network, transport, flow, mechanical stabilization     

叶脉网络功能性状及其生态学意义

叶脉网络结构是叶脉系统在叶片里的分布和排列样式。早期叶脉网络结构研究主要集中在其分类学意义上; 近年来叶脉网络功能性状及其在植物水分利用上的意义已成为植物生态学研究的热点。该文介绍了叶脉网络功能性状的指标体系(包括叶脉密度、叶脉直径、叶脉之间的距离、叶脉闭合度等), 综述了叶脉网络功能性状与叶脉系统功能(包括水分、养分和光合产物等物质运输、机械支撑和虫害防御等)的关系, 叶脉网络功能性状与叶片其他功能性状(包括比叶重、叶寿命、光合速率、叶片大小、气孔密度等)的协同变异和权衡关系, 以及叶脉网络功能性状随环境因子(包括水分、温度、光照等)的变化规律等方面的最新研究进展。此外, 叶脉网络功能性状的研究成果也被应用于古环境重建、城市交通规划、流域规划及全球变化研究中。由于叶脉网络功能性状是环境因子与系统发育共同作用的结果, 未来开展分子—叶片—植物—生态系统等多尺度的叶脉网络功能性状研究, 理清叶脉网络功能性状与气孔失水—茎干导水—根系吸水等植物水分利用的关系, 将为预测植物及生态系统对全球变化的响应提供新的启示。     

Expertise in expert systems: knowledge acquisition for biological expert systems

In this paper it is argued that an expert system requires morethan factual knowledge before it can display expertise in agiven domain. The additional knowledge consists of the heuristicsor ‘rules of thumb’ used by an expert to manipulateand interpret the factual knowledge. The knowledge acquisitionphase of an expert system project involves determining the factualknowledge (which may be obtained from published sources) andthe heuristics used by an expert to manipulate that knowledge-theseheuristics can only be obtained from an expert. In reviewingexisting biological expert systems it is apparent that manycontain only the factual knowledge relating to the domain, andlack the heuristics that enable such systems to show expertise.This paper reviews a number of knowledge acquisition techniqueswhich could be used for acquiring heuristic knowledge and discusseswhen their use is appropriate. The knowledge acquisition techniquesdiscussed are those suitable for the development of small-scaleexpert systems as these are most likely to be of interest tobiologists. The techniques include the use of questionnaires,interview techniques and protocol analysis; particular emphasisis placed on a mod cation to the ‘twenty questions’interview technique which was developed specifically to elicittaxonomic knowledge relating to water mite identification.     

Dpp/BMP transport mechanism is required for wing venation in the sawfly Athalia rosae

The pattern of wing venation varies considerably among different groups of insects and has been used as a means of species-specific identification. However, little is known about how wing venation is established and diversified among insects. The decapentaplegic (Dpp)/bone morphogenetic protein (BMP) signaling pathway plays a critical role in wing vein formation during the pupal stages in Drosophila melanogaster. A key mechanism is BMP transport from the longitudinal veins (LVs) to the posterior crossvein (PCV) by the BMP-binding proteins, short gastrulation (Sog) and twisted gastrulation2/crossveinless (Tsg2/Cv). To investigate whether the BMP transport mechanism is utilized to specify insect wing vein patterns in other than Drosophila, we used the sawfly Athalia rosae as a model, which has distinct venation patterns in the fore- and hindwings. Here, we show that Ar-dpp is ubiquitously expressed in both the fore- and hindwings, but is required for localized BMP signaling that reflects distinct wing vein patterns between the fore- and hindwings. By isolating Ar-tsg/cv in the sawfly, we found that Ar-Tsg/Cv is also required for BMP signaling in wing vein formation and retains the ability to transport Dpp. These data suggest that the BMP transport system is widely used to redistribute Dpp to specify wing venation and may be a basal mechanism underlying diversified wing vein patterns among insects.     

Topological Phenotypes Constitute a New Dimension in the Phenotypic Space of Leaf Venation Networks

The leaves of angiosperms contain highly complex venation networks consisting of recursively nested, hierarchically organized loops. We describe a new phenotypic trait of reticulate vascular networks based on the topology of the nested loops. This phenotypic trait encodes information orthogonal to widely used geometric phenotypic traits, and thus constitutes a new dimension in the leaf venation phenotypic space. We apply our metric to a database of 186 leaves and leaflets representing 137 species, predominantly from the Burseraceae family, revealing diverse topological network traits even within this single family. We show that topological information significantly improves identification of leaves from fragments by calculating a “leaf venation fingerprint” from topology and geometry. Further, we present a phenomenological model suggesting that the topological traits can be explained by noise effects unique to specimen during development of each leaf which leave their imprint on the final network. This work opens the path to new quantitative identification techniques for leaves which go beyond simple geometric traits such as vein density and is directly applicable to other planar or sub-planar networks such as blood vessels in the brain.     

Evolution of wing shape in hornets: why is the wing venation efficient for species identification?

Wing venation has long been used for insect identification. Lately, the characterization of venation shape using geometric morphometrics has further improved the potential of using the wing for insect identification. However, external factors inducing variation in wing shape could obscure specific differences, preventing accurate discrimination of species in heterogeneous samples. Here, we show that interspecific difference is the main source of wing shape variation within social wasps. We found that a naive clustering of wing shape data from taxonomically and geographically heterogeneous samples of workers returned groups congruent with species. We also confirmed that individuals can be reliably attributed to their genus, species and populations on the basis of their wing shape. Our results suggested that the shape variation reflects the evolutionary history with a potential influence of other factors such as body shape, climate and mimicry selective pressures. However, the high dimensionality of wing shape variation may have prevented absolute convergences between the different species. Wing venation shape is thus a taxonomically relevant marker combining the accuracy of quantitative characters with the specificity required for identification criteria. This marker may also highlight adaptive processes that could help understand the wing's influence on insect flight.     

叶脉网络系统的构建和系统学意义研究进展

为了解国内外叶脉网络系统的研究状况,综述了基因、激素对叶脉网络系统发育的调控机理,并剖析了叶脉的功能和系统学意义,分析了光、温度、水和外力破坏等环境因子对叶脉密度、叶脉直径等结构性状的影响。同时,综合考量植物碳投入经济权衡,阐明了叶脉网络系统是在遗传控制基础上由环境与碳投入共同调控建成。最后,对植物叶脉网络系统研究中存在的问题与未来发展方向进行了展望。     

“拉开档次”法的改进及其在河流生态健康评价中的应用

针对“拉开档次”法在进行综合评价过程中不能较好反映评价者主观信息的缺点,并考虑到影响河流生态系统健康的因素具有多层次、不确定和属性复杂等特点,对”拉开档次”法进行改进,并运用改进的”拉开档次”法对流经北京和天津的北运河上、中、下游各区段进行生态健康综合评价.结果表明,北运河上、中、下游各区段生态系统健康评价值分别为0.539、0.521、0.546,生态状况均处于亚健康状态;河流水环境状况对北运河生态系统健康影响程度最大.运用改进后的“拉开档次”法进行河流生态系统健康评价,既兼顾了评价者的主观判断,又包含了数据本身的客观信息,评价过程透明,评价结果科学、合理、客观、可靠,可为河流综合治理提供技术支持和基础依据.     

HIGH-RESOLUTION LEAF X-RADIOGRAPHY IN SYSTEMATICS AND PALEOBOTANY

The foliar vein nets of many seed plants and ferns display systematically informative characters. These venation characters traditionally have been observed by chemically clearing and staining leaves, a process that is slow, involves toxic chemicals, and yields delicate, glass-mounted specimens that require long-term maintenance to prevent or correct bubbling or crystallization of the mounting medium. A technique that uses X-rays and photographic film to produce images of leaf venation consistently shows veins that are 50–100 μm thick. Although the X-ray images are slightly less detailed than the best cleared and stained leaves, the images can be made much more quickly, are more easily stored and reproduced, and do not require permanent alteration of the original herbarium specimen. The technique should facilitate the use of vein characters in systematics, and the identification and systematic analysis of fossil leaves.