Risk-based selection of forest regeneration methods

FOREST ECOLOGY AND MANAGEMENT

卷:115

Article

Zhou, WC

关键词: uncertainty;    stochastic optimization;    regeneration;    planting;    seed-tree method;   

DOI  :  10.1016/S0378-1127(98)00438-1

来源: Elsevier

【 摘 要 】

A stochastic optimization model is developed to select between planting and seed-tree regeneration methods. The model considers the uncertainty of, and the legal requirement on, the stocking level of the established seedling in a given year after regeneration. Uncertainty is quantified as a variation of the mortality rate of the planted seedlings for the planting method and as the prediction error for the seed-tree method. The objective of the forest landowner is assumed to maximize the expected net present value (NPV). Numerical simulations show that the landowner should select the seed-tree method rather than planting for a sample site with a Scots pine stand. In addition, if a risk-free selection model is used, it over-estimates the financial return by about +1.8%. Sensitivity analysis shows that a less restrictive forest act may improve the expected NPV for both planting and the seed-toe method. Sensitivity analysis also shows that a decrease in the variation of the mortality rate (or prediction error) increases the expected NPV. Since these results are obtained only for the sample site, more work is needed to be done until a general conclusion has been drawn. (C) 1999 Elsevier Science B.V. All rights reserved.

【 授权许可】

Free