earticle

영어

This study analyzed site factors affecting the growth of thinned Pinus koraiensis stands in Gangwon-do and Gyeongsangbuk-do, Korea. We investigated 21 site variables, with a focus on soil properties, in 6 regions, where we used 2 types of thinning plots (M;moderate, and H;heavy) and a control. Multiple regression analysis was used to derive tree growth effect factors, specifically mean annual increment (MAI) and periodic annual increment (PAI), based on tree diameter at breast height (DBH) measurements before and three years after thinning. Site factors significantly related to MAI were stand density (-), elevation (-), soil depth in the B horizon (+), and available phosphorus (+). Across regions, thinning intensity had no significant effect on PAI. We found that interactions of the variable thinning intensity with some of the soil physio-chemical variables had an effect on PAI across/within regions. The regression model of PAI against the site variables showed, in descending order, significant results for the elevation, slope, cation-exchange capacity (CEC), effective soil depth, silt, and stand density (R2: 0.924). In conclusion, future studies on the factors affecting tree growth for a species, require first investigation of the optimum environmental conditions for each species, and second application of these results to a soil quality assessment, to ultimately derive the overall characteristics of the site or soil.