Developing a site index model considering soil characteristics for Pinus thunbergii stands grown on the west coast of Korea

Height model of the dominant tree was developed and derived site index curves of Pinus thunbergii, which is the main species of windbreak forests along the west coast of Korea. The site index of a tree is affected by various environmental factors. In the present study, however, the soil characteristics of P. thunbergii stands, which are scattered along the west coast of Korea were used. Eight sites of windbreak forest were investigated from October 2011 to October 2012. The Schumacher polymorphic equation was the most suitable equation to develop a site index model of P. thunbergii stands, and it was the best site index model when Ca-P and fungus were applied to the asymptotic parameter (α). The equation yielded site index curves using the developed model, which is based on trees aged 50 years, considering the soil characteristic factors of P. thunbergii stands in different areas. The site index model and site index curves suggest important growth information, such as windbreak forests, green spaces development, and height growth estimation, which are needed for management of the stands, with consideration of the proposed soil characteristic factors of this study.