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Optimal model formulation for marine ecosystems. - FC0105

R&D Summary objectives:- Describe and model seasonal variations in the nitrogen cycling of a sea loch by constructing a simulation model incorporating its major hydrological and biological features, in support of the SOAFD experimental programme. Key customer purpose:- Provide essential input to SOAFD's strategic research on management of coastal waters, in particular assessing the environmental impact of marine fish farms, including the formation of agal blooms, and setting locational guidelines.
a) The primary aim of the SOAFD project with which this part of the proposed work is associated, is to describe and model seasonal variations in the Nitrogen balance of a sea-loch. The primary objective of the early phase of this work will therefore be the construction and verification of a simulation model incorporating the major hydrological and biological features of the system. Using this simulation model as a starting point, studies of the trade-off between realism and complexity will be made, with particular emphasis on identifying the biological and spatial resolution needed to provide reliable indicators of the likely effects of major external perturbations. The end point of the study will be a suite of simple and intuitive models each capable of addressing a known range of management questions. b) Fish Benthos Interaction The SOAFD program with which this sub-project is associated has as its central aim the experimental identification of the environmental and behavioural factors which expose benthic organisms to fish predation. The early phases of the complimentary theoretical program will involve constructing rule-based models of individual behaviour which explain the time-budgets and attack rates observed in the SOAFD experiments. These behavioural models will be used to construct individual-based population models and to infer population average functional responses. The models thus constructed will be used to investigate the degree of biological detail needed to obtain a dynamically satisfactory representation of the population effects of the fish-benthos interaction. In view of Hassell and May's demonstration of the dramatic changes in dynamics induced by pseudo-interference resulting from predator aggregation onto patches of high prey density, particular attention will be paid to both the representation of such effects and their implications for population stability.
Time-Scale and Cost
From: 1991

To: 1995

Cost: £122,085
Contractor / Funded Organisations
University - Strathclyde
Sea Fish Stocks              
Stock Conservation              
Fields of Study
Fish Health and Aquaculture