Treesearch

Abstract - The depletion of soil moisture within the surface 15 feet by an isolated mature sugar pine and an adjacent uncut forest in the California Sierra Nevada was measured by the neutron method every 2 weeks for 5 consecutive summers. Soil moisture recharge was measured periodically during the intervening winters. Groundwater fluctuations within the surface 50 feet were continuously recorded during the same period. Each fall, a wetting front progressed from the soil surface, eventually recharging the entire soil profile to ""field capacity"". During the recharge period, although the...

In order to evaluate alternative plans, wildland management planners must consider many objectives, such as timber production, recreational use, and community stability. The method presented utilizes the type of qualitative and intuitive information widely available to wildland management planners, and structures this information into a format suitable for decisionmaking. The method makes possible the determination of a measure of overall desirability for alternative plans, and permits the evaluation of plans under alternative value systems. Alternatives are compared through a small set of...

There is an increasing need to clarify the long-term wood supply implications of current harvesting rates. To assess the wood supply and to set timber production objectives, different linear programming techniques are applied to the short and long term. The transportation method is applied to the short term and the B. C. Forest Service computer-assisted resource planning method is applied to the long term.

By using goal programming to enhance the linear programming of Timber RAM, multiple decision criteria were incorporated in the timber management planning of a National Forest in the southeastern United States. Combining linear and goal programming capitalizes on the advantages of the two techniques and produces operationally feasible solutions. This enhancement may also be applicable to linear programming packages other than Timber RAM.

Explicit forest management planning for timber production beyond the first few years at any time necessitates use of information which can best be described as suspect. The two-step approach outlined here concentrates on the planning strategy over the next few years without losing sight of the long-run productivity. Frequent updating of the long-range and short-range plan makes it possible to keep a dynamic posture. Instead of one single objective of maximization of discounted present net worth, there are two objectives. The short-run objective implicitly maximizes the volume or the...

This paper demonstrates the possibility of optimal planning and control of timber harvesting activ-ities with mathematical optimization models. The separate phases of timber harvesting are represented by coordinated models which can be used to select the optimal decision for the execution of any given phase. The models form a system whose components are connected and controlled by means of information flows. A mathematical model is presented for the optimal planning of harvesting activities for the forest enterprise. The use of a mathematical model contributes to the balancing of supply...

Mathematical programming applications in the Forest Service, U.S. Department of Agriculture, are growing. They are being used for widely varying problems: budgeting, lane use planning, timber transport, road maintenance and timber harvest planning. Large-scale applications are being mace in budgeting. The model that is described can be used by developing economies.

A reforestation planning system for the Douglas-fir region of the Western United States is described. Part of the system is a simulation model to predict plantation growth and to determine economic thinning regimes and rotation ages as a function of site characteristics, initial density, reforestation costs, and management constraints. A second model estimates the expected value of alternative reforestation projects and determines the optimum allocation of scarce resources to these projects via linear programming. The applicability of the system to developing countries is briefly considered.

A computerized mapping system originally developed for planning the control of the spruce budworm in Maine has been extended into a tool for planning road net-work development and optimizing transportation costs. A budgetary process and a mathematical linear programming routine are used interactively with the mapping and information retrieval capabilities of the system to determine the allocation and association of wood sources and markets.

Nutzwertanalyse (NUWA) is a psychometric instrument for finding the test compromise in the multiple use planning of forestry, when the multiple objectives cannot be expressed in the same physical or monetary unit. It insures a systematic assessment of the consequences of proposed alternatives and thoroughly documents the decision process. The method leads to a ranking of alternatives based upon weighting of the objectives and evaluation of the contribution of each alternative to these objectives. The use of the method is illustrated with hypothetical data.