Abstract The study explores complex non-linear decisions in land use allocation, focusing on the competition between cash and food crops. We develop an agent-based model to investigate whether the decision to opt for eucalyptus plantation is a rational choice in the perspective of different farmer types. We analyse the negative externalities (i.e. allelopathic effects) caused by the presence of eucalyptus on the productivity of neighbouring plots and the possible spill-over effects. The findings demonstrate that cultivation of eucalyptus as a cash crop may improve the rural populations' well-being only if there are no physical and economical constraints on access to food and services. The model shows that the allelopathic characteristics of eucalyptus strongly affect the soil fertility, inhibiting the possibility to switch to food crops in the future. In addition, the results of policy scenario simulations indicate that government environmental policies can play a key-role in improving awareness of the ecological effects of eucalyptus plantation on soil fertility in fragile socio-economic contexts characterized by high ecological vulnerability.

中文翻译：

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分析水-能源-食物关系中的制约因素：以埃塞俄比亚桉树种植园为例

摘要 本研究探讨了土地利用分配中复杂的非线性决策，重点关注经济作物和粮食作物之间的竞争。我们开发了一个基于代理的模型，以调查选择桉树种植的决定在不同农民类型的角度是否是一个合理的选择。我们分析了桉树的存在对邻近地块的生产力和可能的溢出效应造成的负面外部性（即化感作用）。研究结果表明，只有在获得食物和服务方面没有物质和经济限制的情况下，将桉树作为经济作物种植才能改善农村人口的福祉。该模型表明，桉树的化感特性对土壤肥力有强烈影响，抑制未来转向粮食作物的可能性。此外，政策情景模拟的结果表明，在以高度生态脆弱性为特征的脆弱社会经济背景下，政府环境政策可以在提高人们对桉树种植对土壤肥力的生态影响的认识方面发挥关键作用。