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.

Enhancing local production is key to promoting food security, especially in rural households of low-income countries, but may conflict with limited natural resources and ecosystems preservation. We propose a framework integrating the water-food nexus and a sustainable livelihoods perspective to assess small-scale food production in water-poor regions. We demonstrate it by assessing alternative production scenarios in the Gaza Strip at different spatial scales. At the scale of a single farm, there is a clear conflict among objectives: while cash crops ensure good incomes but contribute scarcely to domestic protein supply, crops performing well from the nutritional and environmental viewpoint are among the worst from the economic one. At the regional scale, domestic production might cover an important fraction of nutritional needs while contributing to household income, but water scarcity impairs the satisfaction of food demand by domestic production alone. Pursuing food security under multiple constraints thus requires a holistic perspective: we discuss how a multidimensional approach can promote the engagement of different stakeholders and allow the exploration of trade-offs between food security, sustainable exploitation of natural resources and economic viability.