Essais sur la gestion des ressources forestières

This thesis consists of three essays. The first two  deal with the design of optimal royalty contracts for forestry exploitation under asymmetric information. The third examines the impact of recycling on the long-run forestry.  The management of forest resources often involves the delegation of the harvesting operation by the forest owner to a harvesting firm. This delegation takes the form of a concession contract in which the forest owner leases logging rights to companies specialized in planting and harvesting, in return for preestablished royalty payments. The royalty (monetary transfers) can be set through different methods. For example, the forest owner can organize an auction among firms. Another way is to negotiate directly with a single firm the terms of the exploitation of the forest and hence the monetary transfers. To set the royalty schedule, the forest owner ideally needs to know the firms' costs, namely the harvesting and planting costs. In practice however firms are better informed about their costs than the forest owner. Under this asymmetry of information, the optimal royalty must therefore take into account informational constraints. The first two essays characterize the optimal royalty and the optimal rotation period under those conditions.  The first essay analyzes the optimal contract under the assumption that the harvesting cost of each firm is perfectly known to itself but not to the forest owner. The problem is examined both in a static context, where the costs are perfectly correlated over time, and in a dynamic context where the costs are intertemporally independent. It is shown that both in the static and in the dynamic cases, the optimal rotation will satisfy a modified version of the Faustmann rule which holds under symmetric information, the modification being necessary in order to induce cost revelation on the part of the harvesting firm. As a result, looking first at the static case, the optimal rotation period will be longer in the asymmetric information case than in the symmetric information case. It is also shown how the cut-off cost can be endogenized, thus increasing the owner's expected profit by making sure that unprofitable forests are not exploited. Finally the comparison is made of the royalty in the symmetric and asymmetric information cases. Because forest contracts are in practice typically linear in the volume harvested, the optimal royalty is derived under the constraint that it is a linear function of the volume harvested and the loss in expected welfare from using a linear contract instead of the theoretically more general nonlinear contract is characterized. Finally, still in the static context, it is shown that the forest owner could raise its expected profit by allowing competition among firms through public auctions. It is shown in the dynamic context that, unlike in the static case, all firms, including the highest-cost type, get a strictly positive rent. It is also shown that the firm's rent rises over time. This is necessary in order to get revelation at a lower cost in the current period. Therefore, the optimal rotation increases over time as well. The optimal contract under asymmetry of information  also has the effect of distorting the lowest-cost firm in this case.  In the second essay, the assumption that the harvesting cost of each firm is perfectly known to itself is dropped. Indeed, in practice neither the forest owner nor the firms know the costs perfectly. Each firm only observes a signal of its cost. For example each firm may be allowed to survey a tract of forest to obtain an estimate (signal) of its cutting cost. Given that its observation is imperfect, a firm's cost will therefore depend on estimations (signals) by the other firms as well, which are private information. This second essay then raises the problem of auction design with firms whose values (costs) are interdependent. In this context, the value of an allocation will depend on the signals of all of the participating firms.  The optimal contract is characterized and the conditions under which the optimal mechanism can be implemented by a second price auction are explored.  The optimal rotation and the reservation price are derived under this auction mechanism.  The third essay studies the effect of recycling on the land area devoted to forestry in the long run. Interest in recycling of forest products has grown in recent years, one of the goals being to conserve trees or possibly increase their number to compensate for positive externalities generated by the forest and neglected by the market.  This paper explores the issue as to whether recycling is an appropriate measure to attain such a goal.  We do this by considering the problem of the private owner of an area of land, who, acting as a price taker, decides how to allocate his land over time between forestry and some other use, and at what age to harvest the forest area chosen.  Once the forest is cut, he makes a new land allocation decision and replants.  He does so indefinitely, in a Faustmann-like framework.  The wood from the harvest is transformed into a final product which is partly recycled into a substitute for the virgin wood, so that past output affects the current price.  We show that in such a context, increasing the rate of recycling will result in less area being devoted to forestry.  It will also have the effect of increasing the harvest age of the forest, as long as the planting cost is positive.  The net effect on the flow of virgin wood being harvested to supply the market will as a result be ambiguous.  An important point however is that recycling will result in less trees in the long run, not more. It would therefore be best to resort to other means if the goal is to conserve the area devoted to forestry.

Keyphrases: Faustmann rule, Optimal forest rotation, Dynamic contracts, Mechanism design, Auction, Adverse selection, Recycling, Land allocation, Alternative uses