Dimensional Analysis for Estimation of Environmental Carrying Capacitiy of Cage Mariculture

In this project a simple and generally applicable relationship for estimating production levels for finfish mariculture has been developed. The resulting equation is to be integrated within the DSS SYSMAR and used in conjunction with numerical model simulations for estimation of the environmental carrying capacity of floating net cages.

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Fish farm in Pegametan Bay, Bali, Indonesia. © K.Niederndorfer

Project Details

Carrying capacity is one of the major components of the ecosystem approach to aquaculture. However its definition and evaluation remains a major difficulty. In this project, dimensional analysis has been used to identify the key drivers and issues surrounding carrying capacity. The aim is to arrive to a simple and generally applicable relationship for estimating production levels for finfish mariculture considering thresholds for particulate organic carbon deposition under the farms.
Results of model simulations are combined with in-situ observations of the sediment deterioration under the farms. Within the areas suited for fish farming, particulate organic carbon transport and deposition are simulated for a wide range of conditions. Figure 1 shows preliminary results of this study. There is a good correlation between the ratio of settled and emitted organic carbon (Mb/Ms), the Reynolds number due to the flow (Re) and the dimensionless settling velocity (Ws*). Further investigations are currently underway to extend the applicability of the equation to for a wider range of conditions.
The resulting equation shall be embedded within the DSS SYSMAR for estimation of environmental carrying capacities. Fig. 2 shows resulting production rates for the Pergametan Bay in Indonesia.

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Fig.1: Maximum production rates within the suitable sites in the Pergametan Bay, Bali

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Fig.2: Maximum production rates within the suitable sites in the Pergametan Bay, Bali

Research division

ECOLAB – Coastal Ecosystems

Coordination

Prof. Dr. R. Mayerle
Research and Technology Centre Westcoast, University of Kiel (FTZ)
Dr. R. Narayanan

Staff

M.Sc. Katharina Niederndorfer (FTZ)
Dr. K-H. Runte (FTZ)

Period

January 2014 onwards