Silvopastoral systems and multi-criteria optimization for compatible economic and environmental outcomes

Abstract

ContextForestry production can provide a valuable commodity and environmental services to complement cattle farming through the mitigation of greenhouse gases (GHG) from meat production, allowing more intensive use of natural resources. ObjectiveThis study addressed the long-term integration of forestry and cattle farming to achieve productive, economic and environmental benefits. MethodsIt was applied Goal Programming and empirical field, cattle, and timber production data and farmer interviews of priorities were used to analyze integrated forestry production of Eucalyptus plantations and cattle breeding and rearing. The preemptive criteria applied were max Forest Net Present Value (NPV), max Cattle NPV, and Carbon Balance. Additionally goals were to minimize the deviation of a normal forest, among others. Results and conclusionsA Type I lexicographical multi-criteria model was developed in three hierarchical models for a 408 ha model farm. Model M1 results in the higher combined NPV Cattle (302,935 US$) and NPV Forest (556,578 US$); Model M2, where NPV Cattle is prioritized at the first level, achieved the target of 317,307 US$ but the least success in achieving carbon positive balance with a negative balance of −20,160 tons of CO2-e released. Comparing the results of model M3, where minimizing the negative carbon balance, a positive carbon balance of +6788 tons CO2-e, in a scenario where the environmental goal would be imposed. The difference of NPV cattle between M2 and M3 is −24,609 US$. The environmental criterion must be allocated to higher hierarchical levels in order to achieve a positive balance and obtain profits from forest and cattle. This also allows quantification of how far removed a system is from achieving a goal of integrated and sustainable production. The lexicographical methodology allowed quantification of results as a function of the hierarchical allocation of various goals within different integration models through studying efficient subgroups. SignificanceIt is shown that environmental and productive objectives can be integrated, even considering harvest of trees in the system achieving economic, environmental and productive goals in the medium or long term, with deviations that the decision maker can accept; plans can also be established with results that can serve as a policy guide, that provide for the incorporation of environmental services. Variations in the models showed the final solution is highly dependent on the preferences order in the higher level; the environmental goal is achievable if it is prioritized at a higher hierarchical level.