The question "Why are there so many species?" has puzzled ecologist for a long time. Initially, an academic question, it has gained practical interest by the recent awareness of global biodiversity loss. Species diversity in local ecosystems has always been discussed in relation to the problem of competi tive exclusion and the apparent contradiction between the competitive exclu sion principle and the overwhelming richness of species found in nature. Competition as a mechanism structuring ecological communities has never been uncontroversial. Not only its importance but even its existence have been debated. On the one extreme, some ecologists have taken competi tion for granted and have used it as an explanation by default if the distribu tion of a species was more restricted than could be explained by physiology and dispersal history. For decades, competition has been a core mechanism behind popular concepts like ecological niche, succession, limiting similarity, and character displacement, among others. For some, competition has almost become synonymous with the Darwinian "struggle for existence", although simple plausibility should tell us that organisms have to struggle against much more than competitors, e.g. predators, parasites, pathogens, and envi ronmental harshness.

Features a new, spatial view of competition and coexistence Provides an overview of regulatory mechanisms that sustain biodiversity in ecosystems Includes supplementary material: sn.pub/extras

Autorentext
Prof. Ulrich Sommer, 1952 in Wien geboren, studierte Biologie und promovierte 1977 am Institut für Pflanzenphysiologie der Wiener Universität. 1985 habilitierte er sich an der Universität Konstanz im Fach Limnologie. Seine Arbeiten über "Konkurrenzbeziehungen des Phytoplanktons" wurden 1985 mit dem Heinz-Meier-Leibnitz-Preis ausgezeichnet. Nach 6 Jahren weiterer Forschungstätigkeit auf diesem Gebiet wurde er 1991 Professor am Institut für Chemie und Biologie des Meeres der Universität Oldenburg. 1994 wurde Professor Sommer an das Leibniz-Institut für Meereswissenschaften an die Universität Kiel berufen, wo er die Forschungseinheit Experimentelle Ökologie leitet. Die ihn vorrangig interessierenden Fragestellungen über Konkurrenz und Fraßbeziehungen innerhalb von Nahrungsnetzen untersucht er sowohl in laborgebundenen Experimenten als auch in Feldstudien in einer Reihe von verschiedenen Meeresgebieten, u.a. Nordatlantik, Ostsee, Nordsee, Rotes Meer und Indischer Ozean. Professor Sommer war vier Jahre lang Associate Editor der Zeitschrift 'Limnology and Ozeanography' und gehört den Herausgebergremien der Zeitschriften 'Aquatic Sciences', Ecology Letters', 'International Review of Hydrobiology, 'Oecologia' und 'Protist' an.

Klappentext

The global loss of biodiversity has led to a renewed interest in the underlying mechanisms that explain spatial differences and temporal change of diversity. This book synthesises recent advances in our understanding of interactions that enhance or diminish coexistence among competing species. It features an innovative, spatial view of competition and coexistence. The chapters are logically grouped and stitched together by the central organising principle of spatial distribution and mobility of competing species and their resources. The text also covers ecological modelling and experimental evidence in the search for general principles across ecosystems, from lake plankton and rocky shore benthos to grasslands and insects.

Inhalt
1 Introduction.- 1.1 The Intellectual Debate Until 1990.- 1.2 Progress During the Last Decade.- 1.3 Consequences for the Structure of the Book.- References.- 2 Competition in Well-Mixed Habitats: From Competitive Exclusion to Competitive Chaos.- 2.1 Introduction.- 2.2 Competition for a Single Abiotic Resource.- 2.3 Resource Storage.- 2.4 Competition for a Single Biotic Resource.- 2.5 Competition for Two Resources.- 2.6 Competition for Three Resources.- 2.7 Discussion.- References.- 3 Spatial Models of Competition.- 3.1 Introduction.- 3.2 Implicitly Spatial Models.- 3.3 Explicitly Spatial Models.- 3.4 Comparing and Connecting Methods.- 3.5 Underlying Spatial Heterogeneity.- 3.6 Competition and Coexistence.- 3.7 Future Directions.- References.- 4 Competition and Coexistence in Plankton Communities.- 4.1 Introduction.- 4.2 Competition Experiments in Laboratory Microcosms.- 4.3 Experiments in Field Mesocosms.- 4.4 Tests of the Intermediate Disturbance Hypothesis by Field Data.- 4.5 Herbivory and Diversity.- 4.6 The Role of Abundance and of Seasonality.- 4.7 Conclusions.- References.- 5 Competition and Coexistence in Mobile Animals.- 5.1 Introduction.- 5.2 Competition Among Mobile Animals.- 5.3 Heterogeneity, Trade-Offs, and Competition.- 5.4 Scale and Heterogeneity.- 5.5 New Challenges.- References.- 6 Competition, Coexistence and Diversity on Rocky Shores.- 6.1 Introduction.- 6.2 Disruption of Competitive Exclusion: The Non-Equilibrium View.- 6.3 Coexistence Through Trade-Offs: The Equilibrium View.- 6.4 Synthesis: Integrating the Effects of Competition, Consumption and Disturbance.- 6.5 Conclusion.- References.- 7 Competition and Coexistence in Terrestrial Plants.- 7.1 Introduction.- 7.2 Competition.- 7.3 Coexistence.- 7.4 Conclusion.- References.- 8 Synthesis: Back to Santa Rosalia, or No Wonder There Are So Many Species.- 8.1 Trade-Offs.- 8.2 Disturbance, Predation and Competition.- 8.3 The Spatial Dimension.- 8.4 Self-Generated Heterogeneity.- 8.5 Exclusive Resources.- 8.6 Slow Exclusion.- 8.7 Equilibrium vs. Non-Equilibrium Concepts.- 8.8 Future Challenges.- References.