ECOTOPE, ROTATION and PESTICIDE are model applications in the framework of optimum control theory.
A typical example of a simulation model, which describes processes of an agricultural--ecosystem, is used to derive optimum management strategies: fertilising schemes, pesticide application and crop rotations. The simulation model for crop growth, nitrogen dynamics in soil and a pest population is based on data series from the collaborative research project 179 ''water- and matter-dynamics in agro-ecosystems'. The model is applied to the environmental conditions of one investigation site of the project: the 'Ohebach' catchment in Lower Saxonia ('Niedersachsen'), Germany.
An application to optimum control theory requires appropriate numerical procedures. Dynamic programming algorithms are used based on general dynamic systems. Numerical effort is decreased by making use of properties of environmental models. This is achieved by a hierarchical approach to the optimization problem. Generic code was developed that is applicable to a general dynamic system.
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R. Seppelt (1999): Applications of optimum control theory to agroecological modelling. In: Ecological Modelling. 121(2-3): 161-183.
R. Seppelt (2000): Regionalised optimum control problems for agroecosystem management. In: Ecological Modelling. 131(2-3), 121-132
R. Seppelt (2001): Hierarchical Dynamic Programming and Applications in Ecosystem Management. In: Environmental Modelling and Software. 16(3):377-386
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