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1.
How is a species' propensity to vary in size over time related to its chances to be listed on the Red List (Red Book), that is to face the risk of extinction? Here I suggest that the linkage between the range of population fluctuations and chance of listing may be established on the basis of the ratio of species' annual fecundity to annual mortality of adults, B/M. For 23 mammalian species inhabiting the vast tracts of Western Siberia, the range of population fluctuations is found to be equal or at least proportional to B/M. Further, this ratio is estimated for a larger set of 90 mammalian species from the territory and coastal waters of the former Soviet Union, of which 25 species are listed in the Red Book of the USSR. The distribution of the Red Book species over the gradient of B/M is clearly non-uniform: most of them have low B/M, which leads to a negative relationship between chance of listing and B/M. The positive relation between population size variability and B/M and the negative relation between chance of listing and B/M suggest the resulting negative relation between chance of listing and population size variability. Both the positive and the negative relations of, respectively, population size variability and chance of listing on B/M are logically justified since B/M is a measure of the population growth rate: it is the total lifetime offspring and an upper estimate of the growth rate per generation time. Fast-growing, more resilient species tend to be more resistant to extinction and hence to have low chance of listing, but simultaneously are able to fluctuate widely. Thus, so long as population growth rate affects both chance of listing and population size variability, high variability implies low chance of listing.  相似文献   

2.
An important task in conservation biology is to assess the spatial scale pertinent for species protection since some species may require protection throughout their distribution, others in only part of their range. Once this is done, species can be correctly identified for listing at different administrative levels (e.g. continental, national, and local). Here, we propose an objective method to list taxa at nested administrative levels based on three criteria (responsibility, rarity and vulnerability). We tested the method using quantitative data on the distribution, abundance and decline of orchids in France. The proposed method enables increased protection status in regions where species’ abundance and diversity are higher, gives priority to species for which an individual administrative unit has high responsibility and allows objective integration of species decline at different administrative levels. The method also enables the integration of locally rare species at their distribution limits and avoids repetition of species listing across second-level administrative units. The use of an objective method such as this could contribute to a standardised system of priority setting that integrates the geographic scale of rarity in relation to different administrative levels for protection.  相似文献   

3.
The moments of bivariate normal distribution, which is truncated with respect to both the random variables, are obtained by using the orthogonal expansion of the distribution and the properties of HERMITE polynomials. In particular the correlation coefficient of the truncated distribution is derived in terms of the actual correlation coefficient. In order to study the effect of truncation tables have been prepared of this correlation coefficient for certain given values of the actual correlation coefficient and for a few selected values of the points of truncation. A listing of the computer program for this purpose is also given.  相似文献   

4.
广西常绿阔叶林的分类和地理分布研究   总被引:14,自引:0,他引:14  
常绿阔叶林是东亚湿润亚热带地区特有的地带性植被类型,群落类型多种多样。作者研究制定了广西常绿阔叶林的分类系统,包括13个群系组、52个群系,列举有代表性的103个群丛。扼要地阐述了它们的地理分布生境特点,为其保护和科学的管理提供基本材料。  相似文献   

5.
A listing of papers and dissertations either using some type of cladistic analysis on a plant group or dealing with theoretical cladistics and written by a botanist. In addition, to facilitate studies in vicariance biogeography, this list includes the distribution of the taxa treated in the various papers.  相似文献   

6.
MOTIVATION: The article presents results of the listing of the quantity of amino acids, dipeptides and tripeptides for all proteins available in the UNIPROT-TREMBL database and the listing for selected species and enzymes. UNIPROT-TREMBL contains protein sequences associated with computationally generated annotations and large-scale functional characterization. Due to the distinct metabolic pathways of amino acid syntheses and their physicochemical properties, the quantities of subpeptides in proteins vary. We have proved that the distribution of amino acids, dipeptides and tripeptides is statistical which confirms that the evolutionary biodiversity development model is subject to the theory of independent events. It seems interesting that certain short peptide combinations occur relatively rarely or even not at all. First, it confirms the Darwinian theory of evolution and second, it opens up opportunities for designing pharmaceuticals among rarely represented short peptide combinations. Furthermore, an innovative approach to the mass analysis of bioinformatic data is presented. CONTACT: eitner@amu.edu.pl SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.  相似文献   

7.
Over four hundred reference guides to the mammalian faunas of almost one hundred and fifty countries, dependencies, and well known, geographically isolated areas are listed, including approximately 60% of the total number of countries found in a current atlas.
Although guides to national mammalian faunas have served as useful synopses for large countries and a useful sub-division for large physiographic/ecological areas, most countries either lack a comprehensive reference to the identity, distribution, behaviour, and local literature on mammals, or the existing work has long required revision. Included in this report is a reference list of some important supra-national areas, preceeding a cross-referenced national listing (by current names, with a chronological listing of references within the country).
National mammal guides are not only an invaluable reference source for the professional, but are also an important stimulus to the layman and government at all levels to take an interest in and appreciate the faunal heritage of mammals found within a country.  相似文献   

8.
The faunistic composition of the family Cossidae (Lepidoptera) of the Socotra Archipelago is revised. Five species are recognized, including two new species (Mormogystia brandstetteri and Meharia hackeri), and dubious identifications and records are discussed. Adults and genitalia are illustrated and bionomic details, DNA barcodes and a synonymic checklist for Socotran cossids are provided. A review of their distribution reveals that at least 80 percent of Socotra's cossids are unique to the archipelago, which is renowned for its endemism. A checklist listing all the species from generas Meharia, Mormogystia, Aethalopteryx, Azygophleps, as well as the synonymy and distribution is provided.  相似文献   

9.
The Molecular Biology Database Collection is an online resource listing key databases of value to the biological community. This Collection is intended to bring fellow scientists' attention to high-quality databases that are available throughout the world, rather than just be a lengthy listing of all available databases. As such, this up-to-date listing is intended to serve as the initial point from which to find specialized databases that may be of use in biological research. The databases included in this Collection provide new value to the underlying data by virtue of curation, new data connections or other innovative approaches. Short, searchable summaries of each of the databases included in the Collection are available through the Nucleic Acids Research Web site, at http://www. nar.oupjournals.org.  相似文献   

10.
The Molecular Biology Database Collection is an online resource listing key databases of value to the biological community. This Collection is intended to bring fellow scientists' attention to high-quality databases that are available throughout the world, rather than just be a lengthy listing of all available databases. As such, this up-to-date listing is intended to serve as the jumping-off point from which to find specialized databases that may be of use in advancing biological research. The databases included in this Collection provide new value to the underlying data by virtue of curation, new data connections or other innovative approaches. Short, searchable summaries and updates for each of the databases included in this Collection are available through the Nucleic Acids Research Web site at http://nar.oupjournals.org.  相似文献   

11.
As one of the 17 megadiverse countries of the world and with four biodiversity hotspots represented in its borders, India is home to an impressive diversity of life forms. However, much work remains to document and catalogue the species of India and their geographic distributions, especially for diverse invertebrate groups. In the present study, a comprehensive and critical list of Indian ant species is provided with up-to-date state-wise distribution. A total of 828 valid species and subspecies names belonging to 100 genera are listed from India. Potential erroneous data, misidentifications and dubious distributional records that may exist in the literature are also identified. The present exhaustive listing of Indian ants will provide a holistic view about diversity and distribution and will also help to identify major undersampled areas where future sampling and taxonomic efforts should be directed.  相似文献   

12.
The Molecular Biology Database Collection: 2002 update   总被引:5,自引:0,他引:5       下载免费PDF全文
The Molecular Biology Database Collection is an online resource listing key databases of value to the biological community. This Collection is intended to bring fellow scientists’ attention to high-quality databases that are available throughout the world, rather than just be a lengthy listing of all available databases. As such, this up-to-date listing is intended to serve as the initial point from which to find specialized databases that may be of use in biological research. The databases included in this Collection provide new value to the underlying data by virtue of curation, new data connections or other innovative approaches. Short, searchable summaries and updates for each of the databases included in the Collection are available through the Nucleic Acids Research Web site at http://nar.oupjournals.org.  相似文献   

13.
Two new species of the genus Staurotheca Allman, 1888 have been studied (Staurotheca cornuta sp. nov. and Staurotheca multifurcata sp. nov). The material, from the Scotia Ridge area (Antarctica), was collected in 1986/1987 by the Spanish Antarctic expedition “Antártida 8611”. Each species is described and figured, and its systematic position among allied species is noted. Data concerning autecology and geographical distribution for each species are given. A comparative table listing the main features of the known species of the genus is included. Finally, a general survey of the geographical and bathymetrical distribution of the known species of the genus is presented. Accepted: 1 September 1998  相似文献   

14.
Gloeocystidiellum rajchenbergii, Hypochnicium patagonicum, Pteridomyces valdivianus, and Stereum greslebinii are described as new species from the Chilean Patagonia. An annotated checklist of corticioid fungi from Chile, listing 94 species with notes on distribution and ecology, scheduled for regular update, is available from http://corticioids.webs.com/checklists.htm.  相似文献   

15.
Distribution of Herbal Remedy Knowledge in Tabi, Yucatan, Mexico. The distribution of herbal remedy knowledge among a group of people is studied for two main reasons: (1) to identify plants that are promising for pharmacological analysis, and (2) to examine the factors that lead to herbal remedy knowledge erosion as opposed to dynamism in the acquisition of knowledge. The goal of this particular study, which is aligned with the second reason, is to establish the variation in herbal remedy knowledge among the Yucatec Maya in Tabi, Yucatan, Mexico. Free listing and cultural consensus analysis revealed that knowledge about a few medicinal plants and herbal remedies was distributed widely among the Yucatec Maya in Tabi, whereas the majority of knowledge was idiosyncratic. This finding was consistent with other studies of herbal remedy knowledge distribution among indigenous groups in Latin America and Africa. Assessing patterns in the distribution of herbal remedy knowledge is an important next step in determining the degree of dynamism or erosion in knowledge acquisition and transmission in Tabi.  相似文献   

16.
The SV40 T antigen database is a listing of plasmids and/or viruses that express mutant forms of the virus-encoded large T antigen protein. The parental virus strain, nucleic acid sequence of the mutations, the effect of the mutation on the T antigen amino acid sequence, and key references are included in the listing. The database is available from the authors as a Macintosh FileMaker Pro file, and as a hard copy printout.  相似文献   

17.
Approximately one fifth of the world's plants are at risk of extinction. Of these, a significant number exist as populations of few individuals, with limited distribution ranges and under enormous pressure due to habitat destruction. In China, these most-at-risk species are described as ‘plant species with extremely small populations’ (PSESP). Implementing conservation action for such listed species is urgent. Storing seeds is one of the main means of ex situ conservation for flowering plants. Spore storage could provide a simple and economical method for fern ex situ conservation. Seed and spore germination in nature is a critical step in species regeneration and thus in situ conservation. But what is known about the seed and spore biology (storage and germination) of at-risk species? We have used China's PSESP (the first group listing) as a case study to understand the gaps in knowledge on propagule biology of threatened plant species. We found that whilst germination information is available for 28 species (23% of PSESP), storage characteristics are only known for 8% of PSESP (10 species). Moreover, we estimate that 60% of the listed species may require cryopreservation for long-term storage. We conclude that comparative biology studies are urgently needed on the world's most threatened taxa so that conservation action can progress beyond species listing.  相似文献   

18.
The RNA Modification Database: 1999 update.   总被引:37,自引:17,他引:20       下载免费PDF全文
The RNA Modification Database (http://medlib.med.utah.edu/RNAmods/) provides a comprehensive listing of naturally modified nucleosides in RNA. Each file includes: chemical structure; common name and symbol; type(s) of RNA in which found and corresponding phylogenetic distribution; Chemical s registry number and index name; and initial literature citations for structure characterization and chemical synthesis. New features include capability to search database files by name or substructural features, modifications in tmRNA, and links to related data and sites.  相似文献   

19.
A Fortran program called SPEFF for evaluation of the effectiveness factor of immobilized enzyme preparations of spherical form in the presence of external and internal mass transfer resistances is described, and a listing of the program is given. Enzyme distribution in the bioparticle may be uniform or nonuniform. In the latter case the enzyme distribution is approximated by fifth-order polynomial. In the program differential equations are replaced by the system of non-linear algebraic equations, and the latter are solved by Newton iteration technique. The program is developed for Michaelis-Menten kinetics with allowance for competitive product inhibition and substrate inhibition. After slight modifications the program can be used for computation of the effectiveness factor of a membrane with an immobilized enzyme, or in the case when the enzyme kinetics are more complex. A typical run on a PDP-11/45 computer took 10-20 seconds. A typical computation time in the case of IBM-compatible TURBO PC was 15-30 seconds.  相似文献   

20.
Noninvasive measures of oxidative stress status in humans.   总被引:8,自引:0,他引:8  
Although oxidative stress is thought to be involved in the pathophysiology of several diseases and aging, it is not routinely measured in clinical diagnosis. This is at least partly because accepted and standardized methods for measuring oxidative stress in humans are not yet established. One of the greatest needs in the field of free radical biology is the development of reliable methods for measuring oxidative stress status (OSS) in humans. A listing of some analytical approaches to measuring oxidative stress is provided as well as a listing of some noninvasive techniques that have been used in humans.  相似文献   

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