Integrating Road Building Decisions into Harvest Scheduling Models
Open Access
Author:
Valdebenito Candia, Victor Alejandro
Graduate Program:
Forest Resources
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
January 22, 2010
Committee Members:
Marc E. McDill, Thesis Advisor/Co-Advisor
Keywords:
Operations Research Harvest Scheduling Models Road building Decisions Forest Resources
Abstract:
Forest planning models have traditionally used a sequential approach to define optimal harvesting and road building schedules. In this approach, a minimum road cost problem is solved in order to satisfy harvest accessibility requirements for previously selected stands using a harvest scheduling optimization model that does not consider road costs. This research incorporates both harvest scheduling and road building decisions in a mixed-integer harvest scheduling model. Alternative formulations for this problem are presented and evaluated, considering tradeoffs between solution quality and computational effort. The advantages of the integrated approach are especially clear in spatially-explicit forest planning because of the importance of accessibility considerations in defining feasible harvest solutions on the ground. The experimental results obtained from the analysis of three real forest landscapes show the advantages of the integrated approach. Results show that significant reductions in road costs can be expected when the integrated approach is implemented. In some cases, the required road length is up to 25% shorter than the road length required by the traditional sequential approach. Even though total revenue improvements for the analyzed forests are less than 2%, it is expected that they would be higher in forests where road costs have more impact on total revenue.
