VERIFICATION OF CARBON STORAGE EFFECT OF WOODEN HOUSES IN THE JAPANESE ALPS AREA USING THE STATISTICAL METHOD

Abstract

 Review of the calculation methods of CO₂ emissions have been carried out, one of which is the handling of harvested wood products (HWP). These arise from end of Kyoto Protocol First Commitment Period. HWP utilizing wood fixed carbon play a role as carbon fixed locations has contributed to the reduction of CO₂ in the atmosphere. There is a movement to evaluate the carbon fixed effect of HWP from the above reasons.
 Lumbers, wood-based panels and papers, which are produced from forests, are managing the domestic forest, become the calculation target of HWP. There is FSC (Forest Stewardship Council) certification as to assess that the forest management has been carried out properly.
 Wooden buildings occupy an important position as a fixed place of carbon. This study estimates the carbon fixed effect of wooden houses in The Japanese Alps Area with a focus on Nagano Prefecture and Gifu Prefecture. In consequence of this study revealed the carbon stocks at the moment in central mountain range, the transition of carbon stocks amount in the case of the wooden housing start has remained as-is, the amount of carbon wooden houses is released by being dismantled.
 We estimated the stock number of wooden houses from the remaining function of wooden houses and the number of future new wooden construction work starting. In addition, we have calculated the timber stocks. To work out it, we multiply by the number of wooden houses to average floor area and wood usage per unit area. We forecasted the number of new wooden housing starts which takes into account the population and economic situation by reference to NRI's study. We used the Weibull cumulative distribution that was revealed in Oikawa et al study as the remaining rate function.
 Estimates of wooden housing stock amount reveal wooden housing stock of Nagano Prefecture and Gifu Prefecture continues to decrease, during the 30 years from 2014 to 2043. The carbon fixed amount of The Japanese Alps Area in 2014 is 950,000 tons, while that in 2043 is 660,000 tons. In this study, we examined the carbon stock fixed in wooden houses when the domestic timber utilization increased to 60%. As a result of the verification, we got the consequence of carbon stock would increase the domestic timber utilization of wooden houses increased. When the domestic timber usage grows, the CO₂ provision of Nagano and Gifu in 2043 is 1,020,000 tons.
 It is important that we grow the domestic timber utilization for wooden structure, with an eye to the augmentation of the carbon stocks in HWP of wooden houses. Furthermore it is significant to raise the use of appropriate woods that have been produced in forest management, and certified by the common agreement such as Forest Stewardship Council. The future tasks of this study are reflecting the concept of long usage, additions and betterments.