QUANTITATIVE ANALYSIS OF TIMBER TRADE AND FOREST PROTECTION

本研究的重点是环境法规对日本、北美洲、中美洲、南美洲和大洋洲之间贸易林产品供应的影响，以寻求林产品贸易与环境保护的平衡局面。我们进行了森林部门分析和森林部门建模。据透露，日本木材的价格可能不够高，不足以支付全部生产成本。据发现，日本的造林成本几乎是主要木材出口国的5至10倍。只要考虑到森林资源，日本就有可能在供应木材满足国内需求方面实现自给自足。在森林部门建模方面，我们认为未来的工作应该：(a)建立具有多个市场层次的空间、跨时间优化模型；(b)审查对跨期福利最大化格式调整灵活性的限制；(c)发展允许联合模拟市场和资源模型的方法，保留它们各自的细节；(d)直接接受现实世界市场/资源状况的“混乱”；(e)明确说明政策情景和预测中固有的不确定性。利用日本林业部门模型，我们的模拟分析表明，减少美国原木进口对国内木材生产没有太大影响，反而加速了对日本的木材进口，这主要体现在关东地区。

This study has focused on impacts, resulting from environmental regulations, on forest product supply to be traded among Japan, North America, Central America, South America and Oceania to seek a balanced situation for forest products trade and environmental protection. We conducted forest sector analysis as well as forest sector modeling. It has been revealed that a price of the Japanese timber may not be high enough to cover the total production costs. Silvicultural costs in Japan are found to be almost five to ten times greater than those in the main timber exporting countries. Only considering forest resources physically, it would be possible for Japan to be self-sufficient in supplying lumber to its domestic demand.Regarding forest sector modeling, we conclude that future efforts should : (a) develop spatial, intertemporal optimization models with multiple market levels ; (b) examine constraints on adjustment flexibility in the intertemporal welfare maximization format ; (c) develop methods that allow joint simulation of market and resource models retaining their respective detail ; (d) directly embrace the "messiness" of real world market/resource conditions ; and (e) be explicit about the uncertainty inherent in policy scenarios and projections. Using the Japanese forest sector model, our simulation analysis indicates that reduction of the US log import does not have much influence on domestic lumber production, instead accelerates lumber import to Japan, which mainly can be observed in Kanto.