Ensuring the Compatibility of Aquatic Habitat and Commodity Production Goals in Eastern Oregon with a Tabu Search Procedure

Abstract

Abstract We present a land management scheduling model for ensuring the compatibility of aquatic habitat quality and commodity production goals in forest management. This model uses Tabu search procedures to select feasible land management activities (timber harvesting and road system management) subject to an even-flow constraint and aquatic habitat quality goals, as represented by stream sediment and temperature indices. The methodology for evaluating the effects of land management activities on the realization of aquatic habitat goals utilizes established procedures, yet makes evaluations with each incremental decision choice. We apply the procedures to a 5,926 ha case study watershed in eastern Oregon to evaluate the performance. For comparison, a global optimum solution is estimated using extreme value theory techniques. Results show that all solutions are spatially and temporally feasible with respect to stream sediment and temperature index goals. Eighty percent of solutions had net present values within 10% of an estimated optimal solution. Further, out of 20 independent runs, one was within 2% of an estimated global optimum, and all 20 were within 15% of the estimated global optimum. While improvements to the model can be made, we have demonstrated that moderately complex aquatic habitat quality evaluation techniques, with spatial elements, can be nested inside a land management scheduling model. For. Sci. 44(1):96-112.