Principaux critères économiques de gestion des forêts : analyse critique et comparative

Abstract

criteria that characterise a capital, productivity criteria that concern the annual output of this capital, efficiency criteria that compare this output to other investment possibilities. As for variables, they are either a quantity (volume), or a revenue, or even a profit resulting from a finite or infinite period. The major consequences of these criteria on optimal forest management are described in the case of an even-aged stand. Figures 1-4 show, in a simplified case and for the output as a function of age, differences obtained from these criteria in the determination of the best rotation age. Figure 5 shows the same kind of result for the output rate of growth as a function of age. Two examples are presented for maritime pine in the south west of France, and for Norway spruce in the north east of France. When it is theoretically studied, the financial market is generally taken as perfect whereas, in reality, it is surely imperfect. Figure 8 shows the difference between these two cases as regards the consumer situation. One conclusion is that the theory can be adapted easily to the real world by using the rate used to borrow or lend money as discount rate according to the situation of borrower or lender of the forest owner under consideration. (© Inra/Elsevier, Paris) forest planning / forest economics / rotation, maturity / discounting

Simulation of silvicultural scenarios and economic efficiency

“…Clutter et al, 1983;Davis and Johnson, 1987;Peyron et al, 1998). where: Ct = net cash-flow at the rotation age (calculated on the basis of the costs paid and harvesting revenues).…”

A simple generalization of the Faustmann formula to tree level

“…Although the approach of Oderwald and Duerr was criticized by Chang (1990), Peyron et al (1998), Rollin (2003), and Heshmatol Vaezin (2006, it can be used to provide an estimate of LEV for uneven-aged stands. The tree market value (TMV) or SMV can be obtained using tree prices, as shown in Table 1.…”

“…Zell et al (2004) and De Turckheim and Bruciamacchie (2005 also presented a set of decision criteria similar to Mize's. However, based on the NPV of one rotation, these criteria did not take land immobilization cost or the annual rent of occupied land into account, and therefore they tend to overestimate tree expectation value (TEV) and harvest age (Samuelson 1976;Peyron et al 1998). Indeed, ignoring land immobilization cost would delay the cut of mature trees, thus excluding nearby trees and subjacent stems from the space required for their growth during the delay period.…”

Simulation and comparison of silvicultural alternatives for even-aged Pinus pinaster Ait stands in Galicia (Northwestern Spain)

“…The criterion net present value of an infinite series (NPVIS) of like rotations [19] was used to determine for each silvicultural alternative, how much is the predicted promise of future income worth today. The NPVIS associated with a given cash flow sequence can be calculated, in a continuous-time formulation, as (5) where C t = net cash flow in period t and i = discount rate [4,19].…”

“…The NPVIS associated with a given cash flow sequence can be calculated, in a continuous-time formulation, as (5) where C t = net cash flow in period t and i = discount rate [4,19]. The basic discount rate considered in the present paper for calculating the NPVIS-values was 0.04 (4%).…”