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1.
Summary The Irish approach to the computer processing of grassland relevés is introduced. A suite of programs in Fortran IV has been developed for the purpose. The preparation and analysis of the relevés using these programs is explained. The cost and ecological effectiveness is discussed. It is concluded that the approach is not radically different to the familiar Braun-Blanquet technique of tabular comparison of relevés.Contribution from the Working Group for Data-Processing in Phytosociology, International Society for Vegetation Science.  相似文献   

2.
Enrico Feoli 《Plant Ecology》1977,33(2-3):119-125
Summary A comparison between centered and non-centered principal component analysis is made on the basis of the resolving power of the methods. The results indicate the appropriateness of using a centered PCA when the aim is an ordination of plant communities, and the noncentered PCA when the aim is to elicit the taxonomic structure of a collection.Contribution from the Working Group for Data-Processing in Phytosociology, International Society for Vegetation Science.This work was supported by the Italian C.N.R. and the Centro di Calcolo dell'Università di Trieste within the framework of a broader project entitled I metodi statistici e le loro applicazioni mediante l'uso dell'elaboratore.  相似文献   

3.
Summary The results presented in this paper suggest that for species to be weighted according to their suitability to characterize isolated groups of relevés in a phytosociological table, the equivocation information may serve as a suitable weight. The appropriate formulations are derived and computed for some data from a salt marsh community.Contribution from the Working Group for Data-Processing in Phytosociology, International Society for Vegetation Science.The author thanks the National Research Council of Canada for support given.  相似文献   

4.
Summary CLUSLA, a computer program for the clustering of very large phytosociological data sets is described. It is an elaboration of Janssen's (1975) simple procedure. The essence of the program is the creation of clusters, each starting with one relevé, as the relevés are entered in the program. Each new relevé that is sufficiently distinct from already existing clusters is considered a new cluster. The fusion criterion is the attainment of a certain level of (dis-) similarity between relevé and cluster. Bray and Curtis' dissimilarity measure with presence-absence data was used.The program, written in FORTRAN for an IBM 370–158 system, can deal with practically unlimited numbers of relevés, provided the product of the number of primary clusters and the number of species does not exceed 140.000. We adopted maxima of 100 and 1400 respectively.After the primary clustering round a reallocation is performed. Then a simple table is printed with information on the significance of occurrence of species in clusters according to a chi-square approach. The primary clusters can be treated again with a higher fusion threshold; or approached with more elaborate methods, in our case particularly the TABORD program.The program is demonstrated with a collection of 6072 relevés with 889 species of salt marsh vegetation from the Working-Group for Data-Processing.Contribution from the Working Group for Data-Processing in Phytosociology, International Society for Vegetation Science. Nomenclature follows the Trieste system, which will be published later.The authors are very grateful to Drs. Jan Janssen, Mike Dale, László Orlóci and Mike Austin for their comments on drafts of the program, and to Wil Kortekaas for her help in the interpretation of the tables.  相似文献   

5.
Summary When a very large number of phytosociological types have to be compared, a reduction of the number of relevés is desirable. In this paper a method of relevé selection from given phytosociological tables is suggested. The method is based on a sum of squares criterion. The advantage, in comparison with other selection procedures, is that this method provides a means on the basis of which the efficiency of a relevé selection can be objectively measured.Contribution from the Working Group for Data-Processing in Phytosociology, International Society for Vegetation Science.The work was completed at the Department of Plant Sciences of the University of Western Ontario, London, Canada. We wish to thank Prof. L. Orlóci for the hospitality and the helpful discussions. The work was supported by Italian C.N.R., within the project Promozione qualità dell'ambiente subproject Metodologie matematiche e basi di dati.  相似文献   

6.
Summary TRGRPS can detect groups or signal if discrete groups cannot be found in a sample. The present paper elaborates on the concepts, describes the algorithm and provides illustrations from syntaxonomy. A computer program (TRGRPS.BAS) is available from the author upon request.Contribution from the Working Group for Data Processing in Phytosociology, International Society for Vegetation Science. For nomenclature of species see Lausi, Beeftink & Kortekaas (1975).The research project, from which this paper summarizes partial results, is supported by a National Research Council of Canada grant. Computer time was provided by the University of Western Ontario.  相似文献   

7.
Summary The concept of structure in phytosociology has been analysed. Three families of structure characteristics have been distinguished: (1) qualitative constituent, (2) quantitative constituent and (3) relational characteristics. Selected structural features are illustrated in some detail and completed by references. The key role of spatial structure has been emphasized and a simple method for the introduction of the parameters of spatial structure in data processing has been proposed. Some remarks to the present syntaxonomy have been added from the spatial structure point of view.Contribution from the Working Group for Data-Processing, International Society for Vegetation Science.Thanks are due to Drs. J. Jenik and J. Kvt for advice and to the Editors for linguistic help.  相似文献   

8.
This paper presents the activities and publications of Organisation for Economic Co-operation and Developments (OECD’s) Working Group on Harmonisation of Regulatory Oversight in Biotechnology and the Task Force for the Safety of Novel Foods and Feeds. The main outputs of the work are the Series of “consensus documents” of the respective groups. These documents compile information which is intended to be used by those involved in the business of risk/safety assessment. These documents are one means of ensuring the transportability of data amongst authorities. An increasing trend in both the Working Group and Task Force is to consider crop species which are relevant to tropical regions and therefore to countries that are not necessarily members of the OECD. For example, the Working Group has recently published a consensus document on bananas and plantains while the Task Force has published a document on cassava. This trend towards crops of greater interest in the tropics is likely to continue into the future.  相似文献   

9.
Some historical notes are presented on the start and early development of the Working-Group for Data-Processing, now Working-Group for Theoretical Vegetation Science, of the International Association for Vegetation Science. One of the major outcomes of the first period of activities in the Working-Group has been the creation of a phytosociological coding and retrieval system to be used in combination with multivariate methods. One branch of classical phytosociology which could have profited much from the Working-Group's achievements, i.e. syntaxonomy, never developed fully into a numerical syntaxonomy and, in fact, it did not develop much at all over the last 20 yr.The next phase in the development of the Working Group is characterized by a strong emphasis on vegetation dynamics. First, these dynamical studies concentrated on real sequences of data from permanent plots, which were treated with the numerical methods available. Later, dynamical models started to be developed in order to predict succession and other forms of long-term vegetation dynamics, for which real data are not available.The third phase, which has been entered only recently, is characterized by an overall emphasis on vegetation theory, from which both the most appropriate choice of numerical methods in any particular case, and dynamical phenomena can be approached. Moreover, vegetation theory is of fundamental importance for the development of the plant community concept and of vegetation typology.In addition, some remarks are made on the growing need for vegetation ecology to cooperate with experimental ecophysiology and population ecology.  相似文献   

10.

Meeting ReportFood and Agriculture Organization

Commission on Genetic Resources for Food and Agriculture Working Group on Plant Genetic Resources for Food and Ggriculture Report on First Session of the Working Group Rome, July 2001 by Roger Hull  相似文献   

11.
12.
A method is described for testing adverse effects of pesticides on the predacious miteAmblyseius potentillae Garman in the laboratory. It complies with the terms of the W.P.R.S./I.O.B.C. Working Group “Pesticides and Beneficial Arthropods” with respect to such methods. Twenty commercial pesticides were tested on the predator as part of a joint pesticide test programme of the Working Group.  相似文献   

13.
The National Center for Human Genome Research and the Department of Energy convened a committee of geneticists and biologists who use the laboratory mouse in their research programs. Their responsibility was to identify goals and guidelines for completing the genetic and physical maps of the mouse genome. The motivation for convening this group was to make certain that existing and anticipated research projects together represent a comprehensive program for addressing the Five Year Goals of the Human Genome Project. Three meetings were held: the first addressed the contributions that the mouse can make to the Human Genome Project; the second meeting reviewed the status of the genetic map, gene mapping research, and genome informatics; and the final meeting evaluated the status of the physical map and physical mapping research. The committee then prepared a report that reviewed the status of the mouse genome project and made recommendations concerning areas of research emphasis. The resulting Request For Applications entitled Mapping the Mouse Genome with Emphasis on Technology Development (RFA: HG92-002) is an important mechanism for coordinating mouse genome research and accomplishing the goals of the mouse genome project. Progress towards complete genetic and physical maps has been impressive. The genetic map should be completed on schedule, and ongoing physical mapping projects are promising. Given rapid progress on these maps, the Working Group proposed expanding the focus of the mouse genome effort to begin planning comprehensive approaches for characterizing the function of the large number of genes that will soon be mapped and eventually sequenced. Partly as a consequence of the Working Group's efforts, discussions have begun among members of the scientific community and National Institutes of Health (NIH) staff to plan comprehensive, efficient, and innovative approaches for studying gene function. The Working Group prepared a report summarizing the status of mouse genome research and recommending areas where effort and funding should be placed. Our report was submitted to and accepted by the NIH and Department of Energy (DOE) and is published here in its entirety.Verne M. Champman, Chair, Neal G. Copeland, Franklin D. Costantini, William F. Dove, Joseph H. Nadeau, Roger H. Reeves, Janet Rossant, Oliver Smithies, and Richard P. Woychik.  相似文献   

14.
In 2003, the FIP Dissolution Working group published a position paper on dissolution/drug release testing for special/novel dosage forms that represented the scientific opinions of many experts in the field at that time (1). The position paper has supported activities, programs, and decisions in the scientific, technical, and regulatory community. Due to the rapid evolution of new practices and techniques for in vitro testing, the FIP Special Interest Group (SIG) on Dissolution/Drug Release decided to revise the previous paper and added proposals for further harmonization of in vitro release testing practices for different pharmaceutical dosage forms. This article represents the current updates to the previously published paper. This revision has been aligned to coincide with the USP taxonomy including route of administration, intended site of drug release, and dosage form. The revised paper includes information from current literature, expert discussions, and presentations from recent workshops (2,3). The authors acknowledge and expect further updates to be made as additional progress is made in the relevant areas. Thus, comments and additional contributions are welcome and may be considered for the next revision of the position paper.  相似文献   

15.
Summary An organization for data-processing in phyto-sociology and plant ccology is deseribed. A good preparation by means of standard sheets for collecting and codifying information from the field is emphasized (Fig. 1). Fig. 2–5 present the arrangement and the logical sequence of the different methods of data analysis (ecological profiles, factor analysis,...) which allows the study of the relations between environmental and floristical variables, in a quick and efficient way. Cooperation with the Ecothèque méditerranéene at Montpellier is both necessary and fruitful. One example is presented using the selection e of 58 relevés of salt marsh vegetation retained by the Working Group for Data-Processing of the International Society for Vegetation Science.
Résumé Les auteurs proposent ici une organisation du traitement des données en phytosociologie et phyto-écologie. L'organisation repose sur un système bien développé pour rassembler et codifier l'information des reléves. (fig.1). Un ordinogramme (Fig. 2–5) présente l'agencement et l'enchaînement des différentes méthodes d'analyse des données (profils écologiques, analyse factorielle, ...) qui permettent d'étudier les relations entre variables du milieu et variables floristiques. La conception de l'enchaînement des fichiers et des programmes de traitement permet d'aboutir assez rapidement aux résultats, facilitant ainsi la tâche du phytosociologue et du phyto-écologue. Ce travail a été réalisé en commun entre le C.E.P.E. Louis Emberger et l'Ecothèque méditerranéenne conduisant à une coopération nécessaire et utile. Une exemple est traité utilissant la sélection e de 58 relevés de milieux salés, sélection retenue par le groupe de travail traitement des données en phytosociologie de l'Association internationale de phytosociologie.
  相似文献   

16.
The side effect of 20 commercial pesticides (10 insecticides/acaricides, 6 fungicides, 4 herbicides) on 6 different beneficial arthropods was tested by members of the IOBC/WPRS Working Group “Pesticides and Beneficial Arthropods” in 3 countries. The tests were done according to standardized methods based on common rules, which, among others, emphasize the reduction of the beneficial capacity as the relevant parameter for evaluation. The beneficials tested were:Trichogramma cacoeciae Marchal,Pales pavida Meig.,Phygadeuon trichops Thomson,Leptomastix dactylopii (How.),Coccygomimus turionellae (L.) andChrysopa carnea Steph. The insecticidal biopreparation Dipel, the acaricide Torque, the fungicides Nimrod, Cercobin-M, Ortho Difolatan, the herbicides Betanal and Illoxan were harmless to slightly harmful to all the natural enemies tested. These chemicals should be examined further for their possible recommendation for integrated control. Other pesticides gave less favourable results. It is hoped that the results would help other WPRS Working Groups and plant protection advisers in the development of rational control programmes.  相似文献   

17.
Summary Corrosion failure of the Pembina pipeline system of North Central Alberta, Canada, was frequent and was associated with constant bacterial load and sulphide in the crude oil and produced water. The bacterial load included a variety of anaerobic and aerobic/facultative bacteria which acted in concert to produce sulphide, giving rise to a cascade of sulphide generation.A total of 256 isolates from the crude oil were tested for ability to reduce oxidized sulphur compounds to sulphide. Five groups of bacteria, (A-E), based on this ability to reduce sulphur compounds, existed in the crude oil system. Group A reduced sulphur compounds with oxidation states +6; and lower, Group B reduced oxidation state +4 and below; Group C, oxidation states +2 and lower. Group D reduced only oxidation state 0 (elemental Sulphur), while Group E could reduce no sulphur compound to sulphide. It was found that a ceiling on the reductive capability of each bacterial group was set by the oxidation state of the sulphur compounds. The result is a synergistic relationship whereby intermediate products of reductive activities of each group form the substrate for subsequent action by other groups until sulphide is produced.  相似文献   

18.
A.F. Bueno  S. Freitas 《BioControl》2004,49(3):277-283
The side effects of twoinsecticides/acaricides, abamectin andlufenuron, on the eggs and larvae of Chrysoperla externa (Hagen) were studied inthe laboratory (25 ± 2°C, 62 ±10% RH and 12-h photophase). The analyticalmethods used were those proposed by theInternational Organization for BiologicalControl (IOBC) – Working Group for Pesticides and Beneficial Organisms. Chrysoperla externa eggviability was not affected by abamectin.Neonate larvae from abamectin sprayed eggs aswell as first, second and third instar larvaethat were directly treated, developed normallyand yielded normal adults. Lufenuron presentedno adverse effects on egg survival. However,lufenuron induced high mortality in neonatelarvae from treated eggs. These neonates, aswell as lufenuron treated first and secondinstar larvae could not molt. In the thirdinstar, high pupal mortality occurred. Theresults showed that abamectin is innocuous andthat lufenurom is toxic to Chrysoperlaexterna eggs and larvae.  相似文献   

19.

Background

Healthcare decision makers face challenges when using guidelines, including understanding the quality of the evidence or the values and preferences upon which recommendations are made, which are often not clear.

Methods

GRADE is a systematic approach towards assessing the quality of evidence and the strength of recommendations in healthcare. GRADE also gives advice on how to go from evidence to decisions. It has been developed to address the weaknesses of other grading systems and is now widely used internationally. The Developing and Evaluating Communication Strategies to Support Informed Decisions and Practice Based on Evidence (DECIDE) consortium (http://www.decide-collaboration.eu/), which includes members of the GRADE Working Group and other partners, will explore methods to ensure effective communication of evidence-based recommendations targeted at key stakeholders: healthcare professionals, policymakers, and managers, as well as patients and the general public. Surveys and interviews with guideline producers and other stakeholders will explore how presentation of the evidence could be improved to better meet their information needs. We will collect further stakeholder input from advisory groups, via consultations and user testing; this will be done across a wide range of healthcare systems in Europe, North America, and other countries. Targeted communication strategies will be developed, evaluated in randomized trials, refined, and assessed during the development of real guidelines.

Discussion

Results of the DECIDE project will improve the communication of evidence-based healthcare recommendations. Building on the work of the GRADE Working Group, DECIDE will develop and evaluate methods that address communication needs of guideline users. The project will produce strategies for communicating recommendations that have been rigorously evaluated in diverse settings, and it will support the transfer of research into practice in healthcare systems globally.  相似文献   

20.
Assessment of the effects of nutrients in running water upon macrophytes is compounded by the variety of additional environmental factors which influence their growth. Some classification schemes have been effective in detecting eutrophication on a national or regional scale, and also downstream changes in large single catchments. However, in lowland rivers with naturally nutrient-rich geologies, detection of change at smaller spatial scales has been difficult. This study examined the macrophyte community at 44 sites on the river Welland, a small lowland catchment rising below 150 m in Leicestershire, England. The community at 23 of these sites was adequate for further analysis. The data show that the clearest effect on community composition is caused by watercourse size. However, sites below sewage works, even small village works, did show a reduction in Mean Trophic Rank, (MTR – an assesment system introduced into the UK over the last three years using a 10–100 scale based upon scores and cover value of indicator species). Overall there was a slight but significant correlation of MTR with soluble phosphate and nitrate. The effectiveness of the MTR method is limited at full catchment scale by low numbers of the indicator taxa at small upstream sites. Catchment-scale assessment of the plant community is probably best served by more detailed phytosociological analysis and by the further development of the habitat templet approach.  相似文献   

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