A linear programming approach for sustainable harvesting schedule for Tectona grandis Linn F. in Omo Forest Reserve, Nigeria

Abstract

Linear programming (LP) is a useful analytical tool for determining future sequence of harvests from the forest. It has been an inherent part of forest management planning and decision-making.This study was carried out to determine the optimal harvesting schedules for Tectona grandis plantations in Omo Forest Reserve, Southwestern Nigeria using Linear Programming. The plantations are being managed for timber production and are to be exploited within twenty-five (25) years based on a 5-year harvesting period. Data was collected from five compartments established in the year 1994, 1995, 2001, 2003 and 2005, and covered an area of 59.5 hectares. A simple random sampling technique was used to select 6 Temporary Sample Plots of size 25 m x 25 m (0.0625 ha) from each compartment. The maximization problem of wood volume on compartmental level was formulated and solved. The solution of the LP showed that about 61,374.5 m³ of wood was maximized. The equivalent numbers of stems (N) of the volume value was 45,985.0. The optimal solution prescribed 17.9 ha (22065.0 m³, 14,181 N) to be cut in period 1(2017-2021); 13.0 ha (9451.0 m³, 9,911 N) is to be cut in period 2 (2022-2026); 10.0 ha (13744.4 m³, 7,809 N) is to be cut in period 3 (2027-2031); 9.5 ha (8879.7 m³, 7,190 N) is to be cut in period 4 (2032-2036) while 9.1 ha (7234.4 m³, 6,894 N) will be cut in period 5 (2037-2041). Sensitivity analysis and opportunity costs were used to highlight the effects of changing some of the model parameters on the prescribed optimal solution.

Keywords: Linear Programming, Optimal harvesting schedules, Tectona grandis, Omo Forest Reserve, Sensitivity analysis