A rule-based system to allocate harvest blocks

Abstract

''The problem of forest management has become one of deciding what actions to perform on what part of the forest and when to provide the desired benefits"(Remsoft Inc. 1994). In a hierarchical forest management plan, it is at the tactical planning level where factors such as the minimum harvest block size, maximum opening size and adjacency delay requirements are considered in order to obtain an operational spatial harvest schedule. Spatial allocations of Deer Wintering Areas, and watercourse buffers is dealt with during this phase as well. Information such as the treatment to take place, specified by the area, timing and on what type of stand is passed down from the strategic planning level. This project had two phases. Firstly, an interview outline was designed in order to determine objectives, constraints, and methods applied by industry to achieve their goals with respect to spatial planning. The interview was conducted with four forest companies. Secondly, based on the survey findings, a rule-based system to allocate harvest blocks was designed using Arc View Geographic Information System (GIS) as a support. Established objectives and goals did not vary significantly from company to company. However, the methods in which they achieved their management plans did vary significantly. Sussex Irving allocated blocks using rules such as oldest first, while St. Anne used a simulation model designed by Remsoft Inc. to do the majority of their blocking (75%) and then followed with an abundance of editing to correct for factors not controlled by the blocking program software. Seven Islands Land Company had a unique view on how management plans should be developed. They focussed on stand management as opposed to the more global view of forest management. They did aggregate stands to form harvest blocks, the size of the stand determined the block size. Black Brook Irving allocated blocks based on a set of rules which determines their need for harvest. Aerial flying was used to identify these stands. The rule-based system designed was based on the objectives and constraints of Seven Islands Land Company. The rule-based system provides an economical alternative to the lengthy process of map colouring or the costly purchase of complex simulation models for simplified cases where adjacency regulations do not apply.