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AbstractThe paper proposes a constructive interpretation of the Post Keynesian debate between horizontalists and structuralists. Both approaches defend an endogenous money theory, but they discriminate between different analyses of the credit market and the reserve market. A more general model encompassing both approaches is presented here and some of its implications are discussed.

Cover -- Half Title -- Title Page -- Copyright Page -- Original Title Page -- Dedication Page -- Preface -- Table of Contents -- I Introduction -- 1 Ecological patterns in time and space -- 1.1 Local structures -- 1.2 Spatial and spatiotemporal structures -- 2 An overview of modeling approaches -- II Models of temporal dynamics -- 3 Classical one population models -- 3.1 Isolated populations models -- 3.1.1 Scaling -- 3.2 Migration models -- 3.2.1 Harvesting -- 3.3 Glance at discrete models -- 3.4 Peek into chaos -- 4 Interacting populations -- 4.1 Two-species prey–predator population model -- 4.2 Classical Lotka–Volterra model -- 4.2.1 More on prey–predator models -- 4.2.2 Scaling -- 4.3 Other types of population communities -- 4.3.1 Competing populations -- 4.3.2 Symbiotic populations -- 4.3.3 Leslie–Gower model -- 4.3.4 Classical Holling–Tanner model -- 4.3.5 Other growth models -- 4.3.6 Models with prey switching -- 4.4 Global stability -- 4.4.1 General quadratic prey–predator system -- 4.4.2 Mathematical tools for analyzing limit cycles -- 4.4.3 Routh–Hurwitz conditions -- 4.4.4 Criterion for Hopf bifurcation -- 4.4.5 Instructive example -- 4.4.6 Poincaré map -- 4.5 Food web -- 4.6 More about chaos -- 4.7 Age-dependent populations -- 4.7.1 Prey–predator, age-dependent populations -- 4.7.2 More about age-dependent populations -- 4.7.3 Simulations and brief discussion -- 5 Case study: biological pest control in vineyards -- 5.1 First model -- 5.1.1 Modeling the human activity -- 5.2 More sophisticated model -- 5.2.1 Models comparison -- 5.3 Modeling the ballooning effect -- 5.3.1 Spraying effects and human intervention -- 5.3.2 Ecological discussion -- 6 Epidemic models -- 6.1 Basic epidemic models -- 6.1.1 Simplest models -- 6.1.2 Standard incidence -- 6.2 Other classical epidemic models.

The olive tree (Olea europaea L.) is among the oldest and most widespread crops in the Mediterranean basin. Portugal is the third olive producer in the European Union, and Trás-os-Montes region, located in northeastern Portugal, is the second Portuguese producing olive region. The olive moth, Prays oleae (Bernard) (Lepidoptera: Praydidae) is a key olive pest in Trás-os-Montes. This pest is a natural host/prey of several organisms which include larvae of generalist and specialist parasitoids as well as generalist predators and entomopathogens. Its most abundant parasitoid is the specialist Ageniaspis fuscicollis (Dalman) (Hymenoptera: Encyrtidae) and this, in Trás-os-Montes region, is commonly followed by the facultative hyperparasitoid Elasmus flabellatus (Fonscolombe) (Hymenoptera: Eulophidae). Spiders represent a relevant group of generalist predators in olive agroecosystems and encompass an important predatory action in agroecosystems as well as an ability to reduce the populations of various insect pests. In this context, a mathematical model, considering the population of the olive moth, the two parasitoids populations and the spider population as the variables in our system, was constructed. The ecosystem steady states for feasibility and stability were assessed. The possible pesticide effects, that represent essentially extra mortality rates for each one of the insect populations, and potential abundance variations on their populations under a climate change scenario were included. Results indicate that the most important natural control agent is A. fuscicollis but in certain conditions E. flabellatus or spiders may be relevant contributors for the pest reduction. This approach may provide a useful tool to assist the field researchers on this pest system and its management. ; info:eu-repo/semantics/publishedVersion

The olive tree (Olea europaea L.) is among the oldest and most widespread crops in the Mediterranean basin. Portugal is the third olive producer in the European Union, and Trás-os-Montes region, located in northeastern Portugal, is the second Portuguese producing olive region. The olive moth, Prays oleae (Bernard) (Lepidoptera: Praydidae) is a key olive pest in Trás-os-Montes. This pest is a natural host/prey of several organisms which include larvae of generalist and specialist parasitoids as well as generalist predators and entomopathogens. Its most abundant parasitoid is the specialist Ageniaspis fuscicollis (Dalman) (Hymenoptera: Encyrtidae) and this, in Trás-os-Montes region, is commonly followed by the facultative hyperparasitoid Elasmus flabellatus (Fonscolombe) (Hymenoptera: Eulophidae). Spiders represent a relevant group of generalist predators in olive agroecosystems and encompass an important predatory action in agroecosystems as well as an ability to reduce the populations of various insect pests. In this context, a mathematical model, considering the population of the olive moth, the two parasitoids populations and the spider population as the variables in our system, was constructed. The ecosystem steady states for feasibility and stability were assessed. The possible pesticide effects, that represent essentially extra mortality rates for each one of the insect populations, and potential abundance variations on their populations under a climate change scenario were included. Results indicate that the most important natural control agent is A. fuscicollis but in certain conditions E. flabellatus or spiders may be relevant contributors for the pest reduction. This approach may provide a useful tool to assist the field researchers on this pest system and its management ; info:eu-repo/semantics/publishedVersion