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1.
812 West Malaysian Orang Asli belonging to four ethnic groups were surveyed for adenosine deaminase (ADA; EC 3.5.4.4) using starch gel electrophoresis. Only the common ADA1 and ADA2 alleles were found, with the frequencies of the latter being 0.025, 0.103, 0.115 and 0.028 in the Semai, Semelai, Temuan, and Jakun groups, respectively. A new 'breeding genetic distance' was applied to these gene frequencies and the Semelai and Temuan were found to be more closely related to each other, and to have considerably more evolutionary flexibility on this scale of 'micro-evolution' than the other two groups. The Semai and Jakun were more similar to each other on the basis of these ADA gene frequencies.  相似文献   

2.
ABSTRACT: Traditional classification systems represent cognitive processes of human cultures in the world. It synthesizes specific conceptions of nature, as well as cumulative learning, beliefs and customs that are part of a particular human community or society. Traditional knowledge has been analyzed from different viewpoints, one of which corresponds to the analysis of ethnoclassifications. In this work, a brief analysis of the botanical traditional knowledge among Zapotecs of the municipality of San Agustin Loxicha, Oaxaca was conducted. The purposes of this study were: a) to analyze the traditional ecological knowledge of local plant resources through the folk classification of both landscapes and plants and b) to determine the role that this knowledge has played in plant resource management and conservation. The study was developed in five communities of San Agustin Loxicha. From field trips, plant specimens were collected and showed to local people in order to get the Spanish or Zapotec names; through interviews with local people, we obtained names and identified classification categories of plants, vegetation units, and soil types. We found a logic structure in Zapotec plant names, based on linguistic terms, as well as morphological and ecological caracteristics. We followed the classification principles proposed by Berlin [6] in order to build a hierarchical structure of life forms, names and other characteristics mentioned by people. We recorded 757 plant names. Most of them (67%) have an equivalent Zapotec name and the remaining 33% had mixed names with Zapotec and Spanish terms. Plants were categorized as native plants, plants introduced in pre-Hispanic times, or plants introduced later. All of them are grouped in a hierarchical classification, which include life form, generic, specific, and varietal categories. Monotypic and polytypic names are used to further classify plants. This holistic classification system plays an important role for local people in many aspects: it helps to organize and make sense of the diversity, to understand the interrelation among plants-soil-vegetation and to classify their physical space since they relate plants with a particular vegetation unit and a kind of soil. The locals also make a rational use of these elements, because they know which crops can grow in any vegetation unit, or which places are indicated to recollect plants. These aspects are interconnected and could be fundamental for a rational use and management of plant resources.  相似文献   

3.
4.
Most countries sharing the Amazon basin have signed the Ramsar Convention on Wetlands of International Importance but still lack complete wetland inventories, classification systems, and management plans. Amazonian wetlands vary considerably with respect to hydrology, water and soil fertility, vegetation cover, diversity in plant and animal species and primary and secondary productivity. Here, we propose a classification system of major natural habitats of Amazonian white-water river floodplains (várzeas) based on hydrological, water and soil chemistry and biological parameters. The Amazonian várzea is one of the largest Amazonian wetlands. It is exceptionally rich in plant and animal species and plays important roles in landscape history, evolution, hydrology and biogeochemical cycles of the Amazon basin. Most of Amazonia??s rural population lives in or along the várzea, emphasizing the economic importance of its natural resources. Our classification indicates five major systems, which are subdivided into 10 main habitats and up to 40 functional (vegetation) units of which the most important mesohabitats are described. We understand this classification as a dynamic system, as it is open to the inclusion of future research attempts and habitats without affecting the entire classification system. Our classification may be used for scientific purposes, such as comparative studies on biomass, productivity, biogeochemical cycles and biodiversity. Also, because the classification builds on habitat types and/or vegetation and functional units already distinguished by the local population it may be especially useful in guiding intelligent use of várzea habitat for specific management activities, such as agriculture, animal husbandry, forestry, fisheries, and conservation.  相似文献   

5.
Classification of vegetation: Past,present and future   总被引:1,自引:0,他引:1  
Abstract. This paper is a report on the past, status-quo and perspectives of vegetation classification, still a major occupation of many vegetation scientists. The history of vegetation classification is discussed against a background of several controversial issues such as the problem of continuum vs. discontinuum, naturalness vs. arbitrariness of the nature of plant communities, universality vs. ad hoc character of syntaxonomic schemes, as well as classical versus numerical approaches to data analysis for classification purposes. The development of the methodology of vegetation science and the present image of vegetation classification is documented by a bibliometric analysis of the publication record of four majorjournals: Journal of Vegetation Science, Vegetatio, Phytocoenologia and Tuexenia. This analysis revealed a persisting controversy between traditional and numerical approaches to vegetation classification. A series of important changes in vegetation science (foundation of new journals, change of editorial policy by the established, important meetings) punctuate a period called the ‘Innovation period’. Several trends in the development of methods of vegetation systematics are summarized under the headings formalism, pluralism, functionalism, pragmatism and indeterminism. Some new features, such as the development and improvement of numerical tools, use of large data banks and attempts to summarize the theory of vegetation classification are discussed. The new growth-form system of Barkman initiated a revival of physiognomy-based vegetation classification. Within this framework the use of the character-type concept and the development of new numerical methods for studying the hierarchical structure of character-set types seems to be a promising approach. The achievements of population biology and ecophysiology have affected vegetation science by emphasizing the functionality of species within plant communities. The use of guilds and other functional groups has experienced an increasing interest from vegetation scientists. Applied in vegetation science, fuzzy-set theory has bridged the techniques of classification and ordination of plant communities.  相似文献   

6.
The comparative analysis of a large number of plant cyclins of the A/B family has recently revealed that plants possess two distinct B-type groups and three distinct A-type groups of cyclins [1]. Despite earlier uncertainties, this large-scale comparative analysis has allowed an unequivocal definition of plant cyclins into either A or B classes. We present here the most important results obtained in this study, and extend them to the case of plant D-type cyclins, in which three groups are identified. For each of the plant cyclin groups, consensus sequences have been established and a new, rational, plant-wide naming system is proposed in accordance with the guidelines of the Commission on Plant Gene Nomenclature. This nomenclature is based on the animal system indicating cyclin classes by an upper-case roman letter, and distinct groups within these classes by an arabic numeral suffix. The naming of plant cyclin classes is chosen to indicate homology to their closest animal class. The revised nomenclature of all described plant cyclins is presented, with their classification into groups CycA1, CycA2, CycA3, CycB1, CycB2, CycD1, CycD2 and CycD3.  相似文献   

7.
Indigenous knowledge provides information on phytotherapeutic potential of medicinal plants for basic health care mangements in local communinites. The present study was aimed to document folklore knowledge of ethnic communities, who are practicing the herbal medicines in the Jhelum valley (District Hattian), Azad Kashmir, Pakistan. The information regarding folklore use of plants was collected from local communities through informed consent semi- structured interviews from 152 key informants. The ethnobotanical data were quantitatively analyzed using indices of use value (UV), relative frequency citation (RFC) and Informant census factor (ICF). A total of 113 medicinal plant species belong to 52 families were documented in the local communites of Jhelum Valley. The Asteraceae and Polygonaceae were the dominant plant families. The plant species hold potential folklore uses against hepatitis, stomach and respiratory problems, tooth ache, skin ailments and tumor treatment. The whole plants (32.52%), leaves ((21.14%)) were highly consumed plant parts and decoction (22.99%), powder form (18.39%) and infusion (13.79%) was the commonly used method for herbal formulation. The species with maximum use value was Beberis lyceum (0.80) and Valeriana jatamansi (0.60). The highest ICF value was obtained for disease catergories that is ear pain (1.00) followed by heaptic disorder (0.94) and urinary system disorders (0.89). The lowest ICF value was recored for nervous system disorders (0.44). The present study disclosed that traditional knowledge of medicinal plants is still widespread in ethnic people, but gradually decline in youngers. Documentation of newly documented plant species with their folklore uses shall uphold further phytochemical and pharmacological studies.  相似文献   

8.
Morphological classification of plant cell deaths   总被引:1,自引:0,他引:1  
Programmed cell death (PCD) is an integral part of plant development and of responses to abiotic stress or pathogens. Although the morphology of plant PCD is, in some cases, well characterised and molecular mechanisms controlling plant PCD are beginning to emerge, there is still confusion about the classification of PCD in plants. Here we suggest a classification based on morphological criteria. According to this classification, the use of the term 'apoptosis' is not justified in plants, but at least two classes of PCD can be distinguished: vacuolar cell death and necrosis. During vacuolar cell death, the cell contents are removed by a combination of autophagy-like process and release of hydrolases from collapsed lytic vacuoles. Necrosis is characterised by early rupture of the plasma membrane, shrinkage of the protoplast and absence of vacuolar cell death features. Vacuolar cell death is common during tissue and organ formation and elimination, whereas necrosis is typically found under abiotic stress. Some examples of plant PCD cannot be ascribed to either major class and are therefore classified as separate modalities. These are PCD associated with the hypersensitive response to biotrophic pathogens, which can express features of both necrosis and vacuolar cell death, PCD in starchy cereal endosperm and during self-incompatibility. The present classification is not static, but will be subject to further revision, especially when specific biochemical pathways are better defined.  相似文献   

9.
The present paper is divided into three parts: 1. The first part is devoted to the review of the historical origin of the modern classification systems of the flowering plants. Early systems of classification since the Aristotelian time provided a basis for the modern schemes of classification. This paper has reviewed briefly the history of plant systematics, which is divided into three periods: the period of mechanical systems of classification, of natural systems of classification, and of phylogenetic systems of classification. The historical development of the plant systems and the basic idea for three periods is discussed respectively. This paper also considers that the studies of the modern classification system have been entering a new period which primarily aims at overall evolutionary respects. 2. Comparison of the modern classification systems of the flowering plants. Four main modern systems (i. e. A. Cronquist 1979, A. Takhtajan 1980, J. Hutchinson 1973 and A. Engler,s system as revised by H. Melchior in Engler,s Syllabus der Pflanzenfamilien 1964) which have greatly influenced the systemstics of plants are compared as to their systematical principles, basic concepts and systematic positions of higher taxa (orders and families) of the flowering plants. The paper is of the opinion that there is still much important work to be done in every field. 3. A review for the modern classification systems of the flowering plants. The paper reviews the modern classification of angiosperms from six aspects: a). The flowers plants are originated from a common ancestral stock; b). The flowers of angiosperms are homogeneous, stamen and carpel are phylletic sporangiophores, all flowers of angiosperms are comparable; c). Monocotyledons are originated from primitive dicotyledons, and represent phylogenetically monophyletic branch; d). The idea advocating the subdivision of Dicotyledoneae into Lignosae and Herbaceae should be rejected as pointed out by many authors; e). The systematical position of Hamamelidae is still a crucial subject for further research; f). The evolutional trends and evaluation of taxonomic characters must be considered in connection with the cor-relation to other characters in question.  相似文献   

10.
ABSTRACT: BACKGROUND: Wild food plants (WFPs) contribute to the nutrition, economy and even cultural identity of people in many parts of the world. Different factors determine the preference and use of WFPs such as abundance, availability, cultural preference, economic conditions, shortage periods or unsecure food production systems. Understanding these factors and knowing the patterns of selection, use and cultural significance and value of wild food plants for local communities is helpful in setting priorities for conservation and/or domestication of these plants. Thus in this study knowledge of wild food plant use among four groups namely Dai, Lahu, Hani and Mountain Han in Naban River Watershed National Nature Reserve ((NRWNNR), Xishuangbanna were documented and analyzed to find the similarity and difference among their plant use. METHODS: Data on wild food plant use was collected through freelisting and semi-structured interviews and participatory field collection and direct observation. Botanical plant sample specimens were collected, prepared, dried and identified. RESULTS: A total of 173 species and subspecies from 64 families and one species of lichen (Ramalina sp.) are used as WFP. There were differences on the saliency of wild food plant species among four ethnic groups. Consensus analysis revealed that knowledge of wild food plant use for each ethnic group differs from others with some variation in each group. Among informant attributes only age was related with the knowledge if wild food plant use, whereas no significant relationship was found between gender and age*gender and informants knowledge of wild food plant use. CONCLUSION: Wild food plants are still used extensively by local people in the NRWNNR, some of them on a daily base. This diversity of wild food plants provide important source of nutrients for the local communities which much of their caloric intake comes from one or few crops. The results also show the role of ethnicity on the preference and use of wild food plants. There is a big potential for harvesting, participatory domestication and marketing of WFPs especially in the tourism sector in the area.  相似文献   

11.
Summary. Plants that parasitise other plants have been among the most difficult plant groups to fit into classification systems due to their modified biology and their often highly reduced morphology. They are now considered to be found in about 16 families of flowering plants. Here we summarise current ideas about their relationships and provide information about their characteristics and utilisation. A major consequence of the revised classification of Orobanchaceae and related families has been the break-up of the traditional Scrophulariaceae, and here we summarise the new classification, focusing on genera of horticultural interest.  相似文献   

12.
物种分类与识别是生物多样性监测的基础, 明确物种的类别及其分布是解决几乎所有生态学问题的前提。为深入了解基于多源遥感数据的植物物种分类与识别相关研究的发展现状和存在的问题, 本文对2000年以来该领域的研究进行了总结分析, 发现: 当前大多数研究集中在欧洲和北美地区的温带或北方森林以及南非的热带稀树草原; 使用最多的遥感数据是机载高光谱数据, 而激光雷达作为补充数据, 通过单木分割及提供单木的三维垂直结构信息, 显著提高了分类精度; 支持向量机和随机森林作为应用最广的非参数分类算法, 平均分类精度达80%; 随着计算机技术及机器学习领域的不断成熟, 人工神经网络在物种识别领域得以迅速发展。基于此, 本文对目前基于遥感数据的植物物种分类与识别中在分类对象复杂性、多源遥感数据整合、植物物候与纹理特征整合和分类算法技术等方面面临的挑战进行了总结, 并建议通过整合多时相监测数据、高光谱和激光雷达数据、短波红外等特定波谱信息、采用深度学习等方法来提高分类精度。  相似文献   

13.
The use of surrogates for biodiversity is a practical tool to improve the cost effectiveness of regional conservation planning. However, there is still much uncertainty about the biological representativeness of surrogates. Using a biophysical classification system known as the Mitchell Landscapes, we compare plant species composition in contiguous versus disjunct units of nine Landscape types and hence the ability of this surrogate to capture patterns of plant species composition. We found that plant species homogeneity was higher within a contiguous Landscape than between non‐contiguous units of the same Landscape. Overall, the dissimilarity between non‐contiguous units and their contiguous counterparts was significant (P = 0.004). Biophysical classes with very high dissimilarities between non‐contiguous units of the same region may be of limited utility.  相似文献   

14.
There is growing realization that intraspecific polyploidy in plants has important implications for the evolution of plant diversity and for plant and plant-herbivore community dynamics. Nonetheless, the rate at which polyploid cytotypes arise and their fate in local mixed-cytotype populations are not well understood. Although within- and especially among-population cytotype variation has been documented in many plants, particularly at the largest (continental) spatial scales, local and regional distributions of cytotypes have been well characterized only for a handful of species. Furthermore, few if any studies have addressed both local and regional patterns in the same plant species with sufficient power to detect cytotype variation on both scales. We assessed the co-occurrence and frequency distributions of diploid, tetraploid, and hexaploid cytotypes of Solidago altissima (Asteraceae) at local and regional spatial scales, sampling across a zone of presumed ploidy-form overlap in the midwestern United States. Determining ploidy by flow cytometry, we found many local populations containing two or three cytotypes, with the relative frequencies of cytotypes varying dramatically even among neighboring populations. AFLP marker data suggest that polyploid cytotypes of S. altissima likely have multiple origins from different diploid lineages. Our results are consistent with recent perspectives on polyploidization as an evolutionarily dynamic phenomenon with frequent multiple origins of higher-ploidy cytotypes.  相似文献   

15.
《新西兰生态学杂志》2011,30(1):150-151
[First paragraph]Improved grasslands pose particular problems in pest management. The areas are extensive and the returns per hectare from grassland agriculture are much less than those from intensive cropping or horticulture, but pastures are usually sown to last for a number of years and have a much more stable ecology than in cropping or horticulture. For these reasons, biological controls and plant resistance have long been the preferred options for managing pasture pests. Within this context, the role of diseases in pasture pest population dynamics has received increasing attention, especially their ability to control pest outbreaks. Diseases are common within our major pasture pest species but their role in population regulation is often difficult to define. One of New Zealand’s major pasture pest species, the grass grub Costelytra zealandica, is widespread and often damaging throughout the country. The insect is an endemic species that has adapted to an introduced pasture system, dominated by exotic plant species (Lolium perene/Trifolium repens), where it can reach populations ten-fold higher than in its native habitat. Such high densities favour disease transmission and it is not surprising that a wide array of pathogens have been recorded from this insect (Glare et al., 1993). But the insect can still be highly damaging and can cause total loss of sown species within 3–4 years from sowing in grass grub prone regions. Probably the most important of these diseases, found throughout New Zealand, is amber disease caused by strains of the bacteria Serratia entomophila and S. proteamaculans. This is an unusual disease, controlled by a bacterial plasmid which has only been found in New Zealand bacterial isolates (Jackson et al., 2001).  相似文献   

16.
17.
1. The anoas are two species of dwarf buffalo, the lowland anoa Bubalus depressicornis and mountain anoa Bubalus quarlesi that are endemic to the island of Sulawesi, Indonesia. The classification of the subgenus Anoa within Bubalus is upheld by assessment of recent genetic and morphological research. The classification of anoas into two species is still debated, but with the absence of significant opposing evidence, this position is adopted here. 2. Information about the distribution of the two species is presented that adds to but largely supports existing reports. However, it is still uncertain whether the two putative species are sympatric or parapatric in their distribution. A review of anoa distribution from historical reports and recent field data (1990s to 2002) highlights their decline throughout Sulawesi, especially in the southern and north-eastern peninsulas. The decline has been attributed to local hunting for meat and habitat loss. Most populations are rapidly becoming fragmented, suggesting that the conservation of viable populations may eventually require management of metapopulations. 3. There is an urgent requirement for conservation efforts to: (i) protect anoas from hunting; (ii) prevent habitat loss in key sites; (iii) complete genetic studies to better determine the number of anoa taxa and Management Units and assess their distribution; and (iv) determine the status of the remaining anoa populations.  相似文献   

18.
Plant diseases have recently increased and exacerbated due to several factors such as climate change, chemicals’ misuse and pollution. They represent a severe threat for both economy and global food security. Recently, several researches have been proposed for plant disease identification through modern image-based recognition systems based on deep learning. However, several challenges still require further investigation. One is related to the high variety of leaf diseases/ species along with constraints related to the collection and annotation of real-world datasets. Other challenges are related to the study of leaf disease in uncontrolled environment. Compared to major existing researches, we propose in this article a new perspective to handle the problem with two main differences: First, while most approach aims to identify simultaneously a pair of species-disease, we propose to identify diseases independently of leaf species. This helps to recognize new species holding diseases that were previously learnt. Moreover, instead of using the global leaf image, we directly predict disease on the basis of the local disease symptom features. We believe that this may decrease the bias related to common context and/or background and enables to build a more generalised model for disease classification. In particular, we propose an hybrid system that combines strengths of deep learning-based semantic segmentation with classification capabilities to respectively extract infected regions and determine their identity. For that, an extensive experimentation including a comparison of different semantic segmentation and classification CNNs has been conducted on PlantVillage dataset (leaves within homogeneous background) in order to study the extent of use of local disease symptoms features to identify diseases. Specifically, a particular enhancement of disease identification accuracy has been demonstrated in IPM and BING datasets (leaves within uncontrolled background).  相似文献   

19.
对金缕梅科现代分类系统的评述   总被引:11,自引:0,他引:11  
为了进一步研究金缕梅科的系统与进化,作者详细介绍了该科的分类历史及各个分类系统;根据现代植物系统学研究的原理和方法,着重对金缕梅科的5个现代主要分类系统,Harms(1930),张宏达(1973,1979),Bogleetal.(1980),Endress(1989)和李建华(Li,1997)进行了详细的分析、比较和评述,在此基础上提出自己的观点,认为李建华的分类系统有一定合理性,但他对个别属的处理和族的划分仍有不妥之处  相似文献   

20.
During the formative period of ethnobotanical studies in the Southwest, Edward Palmer established a standard for reporting useful plants that continues today and Frank. H. Cushing wrote a classic ethnobotany from an anthropological perspective,Z uni Breadstuff. Since these beginnings single tribal studies and, more recently, archaeobotanical investigations have received emphasis. Linguistic studies of plant names and their classification have lagged and synthetic summaries and interpretative explanations of plant use are still demanded. Anthropology’s unique contribution to Southwestern ethnobotany is relating socially shared plant taxonomies and cultural rules for behaving with plants to explain why certain plants are used and others are ignored.  相似文献   

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