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| Preface | |
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| Introduction: intercrops and ecology | |
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| The limited intentions of this book | |
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| The nature of ecological theory | |
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| Some questions of terminology | |
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| Overview of the general theory | |
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| Future use of intercrops | |
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| Structure of the book | |
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| The measurement of intercrop performance | |
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| The bases for comparison | |
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| The problem of population density and planting design | |
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| The yield set | |
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| Criteria for intercrop advantage | |
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| The land equivalent ratio | |
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| Other criteria of success | |
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| Some recurrent statistical problems | |
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| The competitive production principle | |
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| The basic idea | |
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| Some interesting antecedents | |
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| Niche theory, effect-response and yield sets | |
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| Competitive production and environmental grain | |
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| Applying the principle in nature | |
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| Summary and conclusions | |
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| Facilitation | |
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| The basic idea | |
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| Effect-response and the yield set | |
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| Niche theory | |
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| Competition and facilitation together | |
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| The question of grain | |
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| The potential set | |
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| The environmental grain | |
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| More on the potential set | |
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| The potential set, adaptive function and environmental grain - the details | |
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| The range of systems and the potential set | |
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| The adaptive function | |
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| Maximizing yield on the potential set | |
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| The shape of the potential set | |
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| Mechanisms of the competitive production principle | |
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| Partitioning the light environment | |
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| Partitioning soil resources | |
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| The interaction of soil factors and light | |
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| The environments modified to produce facilitation | |
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| Nitrogen | |
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| Water | |
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| Non-nitrogen nutrients | |
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| Protection from pests | |
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| The disruptive crop hypothesis | |
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| The enemies hypothesis | |
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| Trap-cropping | |
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| The detection of facilitation | |
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| Special problems in intercrops involving perennials | |
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| Introduction | |
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| Young perennial plantation with an annual intercrop | |
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| The light environment in a mature plantation | |
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| Some qualitative features | |
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| Diffuse radiation | |
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| The shadow of a canopy | |
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| The shadow with a filtering canopy | |
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| Time in the shadow | |
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| Potential applications | |
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| Weeds and intercrops | |
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| Competitive interactions among three species | |
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| Weed control as indirect facilitation | |
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| Summary and conclusions | |
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| Appendix A | |
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| Appendix B | |
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| Variability and intercrops | |
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| Problems of measurement and evaluation | |
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| Variability, competition and facilitation | |
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| Risk and facilitation | |
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| A simple example | |
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| The adaptive function under risk minimization | |
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| The optimization problem | |
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| Appendix A | |
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| Planning intercrops - a phenomenological approach | |
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| Competition theory for even-aged stands | |
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| A computer-based linear methodology | |
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| The basic idea | |
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| Stabilizing the yields | |
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| Estimating parameters | |
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| An example | |
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| Planning intercrops - a mechanistic approach | |
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| Introduction | |
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| Mechanisms of reduced competition | |
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| Partitioning the light environment | |
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| Partitioning the resource environment | |
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| Mechanisms of facilitation | |
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| Pest and natural enemies dynamics | |
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| Trap-crops | |
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| Planning for weed control | |
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| Summary and conclusions | |
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| Critical research directions for the future | |
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| Dynamic plant growth and interaction models | |
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| The question of mechanization | |
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| The question of genetic improvement | |
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| References | |
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| Author index | |
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| Subject index | |