A stochastic analysis of erosion and economic impacts associated with timber harvests and forest roads

Graduation date: 1976A complex and sometimes serious problem facing modern day forest\ud managers is that of estimating and analyzing potential on-site impacts\ud which result from forest activities. A major type of adverse impact\ud is man-Initiated forest erosion. This consequence can be substantially\ud magnified when forest harvest and road activities are implemented in\ud steep, sometimes unstable terrain, characteristic of much of our\ud Western forest land.\ud The objective of this study was to develop an analysis methodology\ud and a decision model which will assist in evaluation of timber harvest\ud and forest road alternatives and the potential scope of concomitant\ud erosion consequences. The study effort consisted of four distinct\ud parts: 1) development of probability functions for seven individual\ud erosion events; 2) structuring a system model which simulates timber\ud harvest and forest road alternatives in terms of several model products;\ud 3) building an economic model which evaluates added capital costs\ud associated with the erosion potential of each harvest and road\ud for expected road and slope erosion events.\ud The basic goal of this forest system study was to provide land\ud managers with a tool for obtaining additional measurement parameters\ud for proposed harvest and road alternatives. In order to illustrate\ud how such a tool may be applied, the study concluded with an application\ud of the complete methodology for ten well specified harvest and\ud road alternatives. These alternatives ranged from highlead clearcutting\ud to helicopter partial cutting to no harvesting at all. Output\ud of system analysis for these alternatives demonstrated that harvest\ud and road capita]. components and erosion consequences can be integrated\ud jointly into the decision making process