How much primary coastal temperate rain forest should society retain? Carbon uptake, recreation, and other values

In this study, average and marginal approaches for determining optimal pres ervation of primary forests on British Columbia's coast are compared. When the market values from timber, mushrooms, etc., and nonmarket benefits (e.g ., carbon sink, preservation values) of preserving old-growth forests are c onsidered (where the opportunity cost of preserving such forests are the be nefits of commercial forestry foregone), the average method recommends harv est of all remaining old growth. For the marginal approach, a deterministic optimal control model is solved to compute socially optimal stocks of old growth. In this case, the numerical results indicate that large-scale conve rsion of old-growth forests cannot be justified on economic grounds.