A dynamic ecological-economic model as a tool for conflict resolution in an invasive-alien-plant, biological control and native-plant scenario

Abstract The release of biological control agents for the control of environmental weeds is often resisted by parties which utilize these plants. This conflict is difficult to resolve because of the social, economic and ecological complexities involved. We construct an ecological-economic model to simulate the complex dynamics of the release of a biological control agent with the aim of developing a tool which can be used to facilitate conflict resolution in such situations. The model is applied to an environmental weed which has invaded the lowland fynbos ecosystems of South Africa, Acacia saligna; its biological control agent, Uromycladium tepperianum; and a commercially desirable indigenous wildflower plant, Protea repens. The model is parameterized using data from field studies and a number of management scenarios are investigated. The analysis indicates that the benefits of biological control have the potential to outweigh the costs, if the opportunities provided by the biological control agent are exploited. It is concluded that ecological-economic models have much potential for facilitating conflict resolution.

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