Many changes in forests are expected to occur at regional and global level. It is necessary to analyze and estimate impacts quantitatively on forestry industries as a part of the national economy in order to set up policies preparing for future challenges which will be caused by diverse changes in internal-external environment. For the sustainable forest management, establishing a systematical model is essential. This study is aimed at developing a supply and demand structure of timber and byproducts taking into account the factors such as market conditions. Also, this study will provide basic directions for planning the forest resource management schemes and the effective use of forest resources.
The supply-demand structure model for forest products is largely divided into three parts. The first part is about the timber supply, the second part is the wood product market, and the third is the byproduct market. In the first part the study examines the structure of age classes of forest in the long term and the possibility of domestic timber supply on the basis of the governmental forest plans. Timber supply is assumed to come from the timber harvest, species regeneration, logging in damaged areas, and thinning. To estimate the dynamic changes in areas by age classes, Cohort correlation developed in 2008 was applied. The supply-demand model for the wood product market is composed of main products including sawnwood, plywood, particle board, fibreboard(MDF), and pulp. Functions such as supply, import demand, and demand were estimated for each product to establish the model. For the forest byproduct market, analyzed items are chestnuts, astringent persimmons, jujubes, oak mushrooms, and wild edible greens. The absence of time series data for cultivation areas led to the usage of producer price and production input price for the estimation of supply function as a general function type. Thus, this is a long-run model which is not limited by cultivation areas.
The result of analysis of timber supply in the model will shows that the age class 6 which was only 7.7% of the entire forest practice area in 2010 will dramatically increase. Accordingly, it will increase to around 73% of the whole forest practice area by 2100. In the timber supply, timber harvest is expected to account for 93~95% in the timber production. For the wood products, the domestic supply and import of sawnwood, plywood, and fibreboard made of roundwood are expected to decline. The reason for this decrease is from the prediction of the increase in international and domestic prices for raw materials due to environment protection and the weaponization of resources. The total supply of particle board made of recycling wastewood and pulp made of wood chips will increase. As a result of a comparison between the outlook of products supply in the product market and the outlook of the domestic timber supply, possible domestic timber supply is only 2,130,000㎥ of roundwood and the self-sufficiency will be merely about 15% in 2015. Self-sufficiency, however, will increase to around 83% by 2050. The result of supply-demand analysis for the forest byproducts shows that the domestic supply of astringent persimmons will increase, while the import will decrease. Likewise, the domestic supply of wild edible greens will increase and the import will decrease. Also in the case of oak mushrooms, domestic supply will grow, dropping imports.

Researchers: Sang-Min Lee, Kyung-Duk Kim, and Seong-Hwan Song
E-mail address: smlee@krei.re.kr