This thesis is about the classification and mapping of ecosystems, essential for an integratedgeographical approach to environmental management which takes into account spatialdifferentiation. To... Show moreThis thesis is about the classification and mapping of ecosystems, essential for an integratedgeographical approach to environmental management which takes into account spatialdifferentiation. To this end, it considers man's environment as an ecosystem, follows asystems approach and attempts to purposively connect at least three systematic angles forecosystem analysis, viz.:ecosystem processes (corresponding with the central themes of environmentalmanagement);the vertical structure of main ecosystem components (corresponding with themedia of environmental management);the horizontal patterns of ecosystems (to account for spatial variability and ageographical orientation to environmental management). Show less
A unifying framework is presented for describing the phenotypic coevolutionary dynamics of a general ecological community. We start from an individual-based approach allowing for the interaction of... Show moreA unifying framework is presented for describing the phenotypic coevolutionary dynamics of a general ecological community. We start from an individual-based approach allowing for the interaction of an arbitrary number of species. The adaptive dynamics of species's trait values are derived from the underlying population dynamics within the community; in consequence, the evolutionary process is driven by ecological change. We present a hierarchy of dynamical models for the investigation of coevolutionary systems. The necessity of stochastic treatment is demonstrated and deterministic approximations are derived where appropriate. The mathematical framework advanced here to our knowledge is the first one to combine the individual-based, stochastic perspective with a fully dynamical analysis of the phenotypic coevolutionary process. The hierarchy of models presented is particularly geared to infer evolutionary predictions from ecological assumptions. Applications to evolutionary dynamics both in predator-prey systems and under asymmetric competition demonstrate the versatility of our approach. Rich coevolutionary patterns are obtained and novel evolutionary phenomena are revealed. Deductions are given to derive various well-known equations from the literature of evolutionary modelling. Consequently the different domains of validity for these models are delineated and several ad-hoc assumptions are removed. In particular, equations central to the fields of evolutionary game theory, adaptive dynamics, replicator dynamics and reaction-diffusion models of phenotypic evolution are recovered and are identified as special cases within a dynamical theory of coevolution. Show less
