Effects of Stand Density on Carbon Dynamics in a Larch (Larix leptolepis) Plantation

Abstract

This study was conducted to evaluate forest carbon dynamics on two different stand densities in a 36-year-old larch(Larix leptolepis) plantation, Korea. Aboveground carbon storage, litterfall, litter decomposition, soil carbon storage and soil respiration rates on high(600 trees/ha) and low stand density (387 trees/ha) were measured for two years. Aboveground carbon storage and increment of the high stand density were generally higher compared with the low stand density due to effect on stand density. Organic carbon inputs by needle litter were significantly higher in high than in low stand density. Needle litter decomposition rates were not significantly different between both stand densities. However, decomposition rates in fine roots were generally higher in high than in low stand density. Soil carbon concentration and storage were not significantly different between both stand densities at each depth. Soil respiration rates were relatively similar between both stand densities during the study period corresponding with the fluctuation of soil temperature, while soil moisture content was not related with soil respiration. The results indicate that carbon dynamics in this larch plantation were not affected by stand density except for needle litter production and aboveground carbon increment by a tree basis.