Modelling of radiocesium transfer in the lichen-reindeer/caribou-wolf food chain

Abstract

The environmental contaminate radiocesium (cesium-137) has been shown to be of value as a marker in food selection and intake studies. Its greatest potential value as a food marker is in the subarctic/arctic regions, particularly in the lichen to reindeer/caribou to wolf food chain. A kinetic model describing the movement of radiocesium through the food chain has been developed using the SAAM computer program and is presented here. The program has been written so that the various paramenters affecting the transfer of radiocesium in the food chain can be altered more realistically to describe the system being modeled. The values of the parameters as given in this example are realistic for interior Alaska, however caution should be exercised in the application of the present results to regions that may be vastly different from the Alaskan interior without first evaluating the parameters and assumptions of the model

Concentrations of 137Cs in lynx (Lynx lynx) in relation to prey choice

“…The model was similar to that used for wolf by Holleman et al (1990). Parameter estimates were obtained by fit to a build-up curve for 137 Cs concentrations in a 20 kg animal with a biological half-time of 35 days (Mohn and Teige, 1968).…”

Modelling radiocaesium transfer and long-term changes in reindeer

“…Eberhardt and Hanson, 1969;Golikov et al, 2004). More complex models have been suggested (Gaare and Staaland, 1994;Holleman et al, 1990), but they have not been compared to measured activity concentrations in reindeer. A difficulty is that the diet of reindeer is complex, involving a large variety of plant species (Gaare and Skogland, 1975), and there is little knowledge about the uptake and depletion of radiocaesium in most of the individual species.…”