Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

The Theory of Island Biogeography

Ecology versus History as Determinants of Patchy and Insular Distributions in High Andean Birds

A study of habitat conditions of the macrophytic vegetation in selected river systems in western Lower Saxony (Federal Republic of Germany)

EnglishThe mediterranean forest are a naturel milieu, instable and deeply disturbed by man's action. From an historical point of view, their regression can be assessed from the beginning of the Neolithic and especially during the last century. The situation is quite different in the Northern mediterranean countries where, following an intensive land abandonment and in spite of dramatic fires, their surface is generally increasing whereas, in the Southern mediterranean countries, forests are quickly destroyed under combined action of man and cattle. From an ecological point of view, the mediterranean forests constitute very heterogenous units where, according to climatic and edaphic criteris, one can characterize forests, preforests and pre-steppic forests. Their dynamic significance varies essentially according to the types of bioclimate but also according to the species. Their phytosociological significance is nowadays known and a synthesis is attempted. The conservancy of the mediterranean forestsalready presents with serious problems as well for the species, some of them becoming nearly extinct, as for the structures of vegetation. Their protection press the urgency of immediate action. francaisLes forets mediterraneennes representent un milieu naturel fragile et profondement perturbe par l'action de l'homme. Du point de vue historique, il est utile d'estimer dans la mesure du possible, la regression qu'elles ont subie depuis le debut du Neolithique, et tout specialement au cours du dernier siecle. La situation est totalement differente dans les pays du revers septentrional oil a la suite dune intense deprise rurale et malgre de dramatiques incendies, leur superficie tend globalement a s'accroitre, alors que dans les pays du revers sud, on assiste a une destruction acceleree du capital forestier sous faction conjuguee de l'homme et de ses troupeaux. Du point de vue ecologique, les forets mediterraneennes constituent des ensembles tres heterogenes, oil, en fonction des criteres climatiques et aussi edaphiques, Ion est amene a distinguer des structures franchement forestieres, des preforets et des forks pre-steppiques, dont la signification dynamique vane essentiellement suivant les types de bioclimat, mais aussi des essences constitutives. Leur signification phycosociologique est actuellement assez bien connue et un essai de synthese est tente ici. Du point de vue de leur conservation, de dramatiques problemes se posent des a present aussi bien au niveau des essences, dont certaines se trouvent en situation naturelle proche de l'extinction, que des structures de vegetation. Des solutions d'urgence devront etre trouvees dans les plus brefs delais, pour assurer leur sauvegarde

/pdf/les-forets-mediterraneennes-problemes-poses-par-leur-4oxe607xfm.pdf

Les foréts méditerranéennes problemes posés par leur signification historique, écologique et leur conservation

The new trends in agricultural policy in Western Europe conduct to new management problems in maintaining and utilizing biological resources. In the South-Western France, the evolution of agricultural practices occurs in two opposite ways. On one hand, the intensification of agriculture leads to simplify the landscape by hedgerows removal, grasslands ploughing and drainage for corn cultivation. On the other hand, the decreasing numbers of cattle and sheep conduct the less fertile parts of the territory to evolve into fallow. These two processes are closely linked on a same territory and important interactions exist between intensive agricultural areas and semi-natural communities. To understand the importance of these interactions and their role in ecological stability of landscapes, we use passerine bird communities as an ecological indicator. We modelized the relationships between birds and landscape structure from 256 releves. Each releve includes a bird count point of 20 mn and a description of the landscape feature on the surrounding 6.25 ha. An ordination of the releves along the main ecological gradients was realized using Correspondence Analysis. Then, these ordinations where related to the landscape structure with Stepwise and Multiple Regression Analysis. The rate of woody area, the hedgerow network complexity and the rate of fallow land are the main ecological gradients. We have used this model to measure the importance of the changes induced on landscape by a range of management practices differing in intensity. To achieve this aim we compare the displacement of 116 releves along the ecological gradients between 1983 and 1988. The changes occurring both in bird composition and landscape structure reveal the ecological impacts of the different management practices (hedgerow removal, drainage, ploughing, decreasing grazing pressure). We examine the behaviour of ecological diversity of landscape units differing in structure and use.

Modelling bird communities/landscape patterns relationships in a rural area of South-Western France

La position biogéographique du Mont Ventoux aux confins des biomes médioeuropéen, alpin et méditerranéen, sa puissance altitudinale de quelque 1 600 m et sa situation d'éperon avancé de l'arc préalpin français poussant une extrême avancée vers le sud-ouest, font de ce massif un «univers biologique» de tout premier plan où s'affrontent et s'entremêlent des tendances éco­ logiques et biogéographiques singulièrement contrastées. Nous en verrons la nature et les implications théoriques et pratiques tout au long de ces pages. Par ailleurs, l'histoire mouvementée et exemplaire à plus d'un titre qu'a connue la montagne, et qui fut retracée par Maury (1960), permet au biologiste d'apprécier et parfois de mesurer les effets des manipulations forestières sur les communautés. Tous ces atouts d'ordre biologique ainsi que l'impulsion donnée par la Délégation Générale à la Recherche Scientifique et Technique à une étude d'ensemble du massif jus­ tifièrent largement l'étude de longue haleine que nous avons menée dans le Ventoux depuis six ans, et dont le présent article se veut être une synthèse.

L’avifaune du mont Ventoux essai de synthèse biogéographique et écologique

This contribution presents a system of data–processing which has gradually been developed at our institute to solve concrete problems arising in the various vegetation studies carried out here. The system comprises a data storage and retrieval system as well as a series of statistical tests and multivariate methods for use in ‘phytosociology and ecology’, (cf. the name of our institute). According to our usage these terms have the following meaning. Phytosociology is considered as the study of relations between plants, sensu Krylov (1898). or the study of plant associations. ‘associations vegetales’. sensu Guinochet (1973). Plant (or vegetation) ecology is considered as the study of the relations between vegetation and its environment, including studies of indicator species and ecological groups, and subsequent analyses of vegetation structure and distribution ecology of animal species (e.g. birds and molluscs). This definition of phytosociology deviates from definitions such as of Braun–Blanquet (1932). Cain (1944) and Becking (1957) which include environmental relations (Cf Westhoff & van der Maarel 1978 for a review of the Braun–Blanquet approach which emphasizes synecology as an essential approach in phytosociology).

Elements for a system of data processing in phytosociology and ecology

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L’avifaune du mont Ventoux essai de synthèse biogéographique et écologique

Elements for a system of data processing in phytosociology and ecology