Integrating gum production and selected forest ecosystem services into forest management plans using linear programing: A case study in Sudan

Abstract

Nowadays, with the need for multi-objective planning to maximize the utility of forest resources without damaging ecological integrity, the traditional view of forest management has to change. In this study, in addition to the production of wood, which is easy to materially evaluated, other values of forests have been highlighted for the selected study area, Okalma forest in Sudan. Gum arabic production, soil conservation and water production values were tried to integrate into forest management plan in addition to timber production. These values were first connected with forest structure using regression models to generate gum arabic, soil loss, water production and timber production yield tables. Afterwards, a linear programming model was developed to integrate those values and solved by LINGOTM. Six alternative planning strategies were generated based on the integration of various objectives such as maximization of gum arabic or timber production with different constraints such as harvest flow or capital amount of ecosystem services. When each strategy was compared; STR2, which aimed to maximize timber production, generated the highest NPV of water production as (€ 1,859.4 million), and STR5 generated the lowest NPV of soil loss as (€ 245.5 thousand) at the end of 25 years planning horizon. Among the strategies used to maximize the gum arabic production, STR1 generated the highest NPV of gum production (€764.3 thousand) at the end of the planning horizon. In conclusion, forest management plans should be objectively designed to include multiple services and products.