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The use of phytosociological methods in ecological investigations, III. Pratical application / M.E.D. Poore in Journal of Ecology, Vol. 43, n°2 (Année 1955)

Public [article]  inJournal of Ecology > Vol. 43, n°2 (Année 1955) . - pp. 606-651 Titre : The use of phytosociological methods in ecological investigations, III. Pratical application Type de document : texte imprimé Auteurs : M.E.D. Poore, Auteur Année de publication : 1955 Article en page(s) : pp. 606-651 Langues : Anglais (eng) Mots-clés : phytosociologie  écologie Résumé : "In two previous articles (Poore, 1955a, b) I have given a review of the methodology and practice of the Braun-Blanquet school of plant sociology, and a discussion of some of the problems which these raise. It has transpired that there is no proven theoretical basis for much of the system, which consists instead of a series of empirical treatments. Its justification, if indeed it is justified, lies in its application. Clearly, then, any fair verdict should be based on the results of practical trials rather than on theoretical grounds. Accordingly, a field study was undertaken during the summer of 1952 in the Breadalbane area of Perthshire. This region (and particularly the mountain part of it), was chosen for several reasons: I was already fairly familiar with the vegetation and flowering plants, and so could dispense with the primary survey which should precede a sociological study; much of the original and best Continental sociology had been carried out in the mountains of Central Europe and Scandinavia, and it was possible that mountain communities were the most amenable to this kind of treatment; the vegetation was relatively little affected by human interference; and the area was floristically rich by British standards, and might be expected to show species of high fidelity. My first concern was the clarification of problems of sociological technique, and not explanation of the ecology of the various communities. Naturally, however, the two cannot be divorced from one another; and, as the work proceeded, it became obvious that, quite apart from its value for the description of vegetation and possible use for collecting data for the classification of plant communities, the 'sociological ' technique was very useful for synecological studies in a way which is not indicated by its disciples. I believe this to be only a systematic application of the kind of observation and inference which every experienced field ecologist is accustomed to use, without, perhaps, always realizing their implications. But in this lies the great importance of the method." (source : auteur) Type de publication : périodique Référence biblio : Poore M.-E.-D., 1955 - The use of phytosociological methods in ecological investigations, III. Pratical application. Journal of Ecology, 43 (2) : 606-651. ID PMB : 55203 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=55203 [article]

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Germination and Establishment of Juncus Effusus L., II. The Interaction Effects of Moisture and Competition / Alec Lazenby in Journal of Ecology, Vol. 43, n°2 (Année 1955)

Public [article]  inJournal of Ecology > Vol. 43, n°2 (Année 1955) . - pp. 595-605 Titre : Germination and Establishment of Juncus Effusus L., II. The Interaction Effects of Moisture and Competition Type de document : texte imprimé Auteurs : Alec Lazenby, Auteur Année de publication : 1955 Article en page(s) : pp. 595-605 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Juncus effusus [Thèmes] Germination des graines Mots-clés : semis  sol agricole  graminée  semence  trèfle  sol à texture grossière  compactage du sol Résumé : "1. In order to study the effects of available moisture on germination and early establishment of Juncus effusus, and of competition under these conditions, seeds of J. effusus were sown at different water-tables alone and with two mixtures of grass and clover. 2. There were great differences in the numbers of Juncus plants establishing under different conditions of available moisture. At the end of the first experiment 540 seedlings were removed from all mixtures sown with the water-table up to the soil surface, whilst no seedlings established under the very dry conditions produced by a water-table 8 in. (20 cm.) below the soil surface. 3. Sown species had less influence on initial establishment of Juncus seedlings than had available moisture. There were, however, considerable differences in the effects of companion species on subsequent development of the seedlings. The mean weights of seedlings removed from pots of J. effusus sown alone, J. effusus + Lolium perenne + Trifolium repens, and Juncus effusus + Agrostis tenuis + Trifolium repens--all with a water-table up to the soil surface--were 96.9, 13.3 and 12.6 gm. respectively, whilst the mean numbers of seedlings removed were 37.0, 28.2 and 24.2. 4. Counts of plant numbers and air-dry weights were taken of the species sown with Juncus effusus and a comparison has been made of the relative germination and subsequent development of these species in relation to J. effusus under different conditions of available moisture. 5. The discussion includes a short account of the practical importance of these results particularly in relation to the data presented in an earlier paper." (Lazenby, 1955). Type de publication : périodique Référence biblio : Lazenby A., 1955 - Germination and Establishment of Juncus Effusus L., II. The Interaction Effects of Moisture and Competition. Journal of Ecology, 43 (2) : 595-605. ID PMB : 69084 DOI : 10.2307/2257013 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69084 [article]

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