Search

We developed a simple forest soil carbon model (Korean Forest Soil Carbon model, KFSC) requiring a small number of parameters to evaluate the forest soil carbon stocks and dynamics. The KFSC was composed of live biomass (BIO), primary dead organic matter (DOM) (AWD: aboveground woody debris; BWD: belowground woody debris; ALT: aboveground litter; and BLT: belowground litter), and secondary DOM (HUM: humus and SOC: soil organic carbon). The KFSC was validated against six Pinus densiflora forests at Gyeonggi province in central Korea and validation results showed that the model predicted the AWD, ALT, and SOC stocks with high precision (r 2=0.90–0.98, slope = 0.95–0.98). We simulated 160 years of carbon dynamics of the P. densiflora forests in Gyeonggi province (11,607 ha) under alternative clear-cut intervals that had been taking place in the past (30, 50, and 80 years). Simulated total SOC stock ranged from 298.7 to 520.5 Gg C depending on the scenario and increased with time in all scenarios. Th...

This study was conducted to examine the soil aggregate distributions and their relationship with microbial biomass carbon (C) concentration and soil C in Pinus rigida and Larix kaempferi plantations. Soil samples of 0–10 cm, 10–20 cm, and 20–30 cm depth were collected and the microbial biomass C concentration was measured. The soils were then classified into four aggregate size classes by wet-sieving procedure [large macroaggregate (>2000 μm), small macroaggregate (250–2000 μm), microaggregate (53–250 μm), and silt-plus-clay (

The minirhizotron technique was used to investigate the spatial (soil depth) and temporal (season) changes of fine roots (≤2 mm) in a mature Pinus densiflora forest. Length, production, and mortality of fine roots were measured at different depths on seven dates between March and October 2011. Average fine root length (mm cm−2), production, and mortality (μm cm−2) during the growing seasons were 2.54 ± 0.82, 84 ± 27, and 7 ± 4 at 0–20 cm depth, 0.85 ± 0.37, 39 ± 13, and 14 ± 9 at 20–40 cm depth, and 1.26 ± 0.92, 45 ± 28, and 34 ± 16 at 40–60 cm depth, respectively. There was no significant difference in length, production, or mortality of fine roots among the different seasons and depths (P > 0.05). The seasonal pattern in fine root length generally increased during the growing seasons. The fine root production was high in summer, whereas the mortality was high in autumn. This preliminary result using a minirhizotron technique can be used for quantifying and understanding the fine root dynamics in P. dens...

We investigated the mass dynamics of coarse woody debris (CWD) in an old-growth deciduous forest dominated by Quercus serrata, Carpinus laxiflora, and C. cordata in a 1 ha permanent plot of the Gwangneung Experiment Forest, Korea, from 2002 through 2010. CWD mass varied from 16.8 to 34.2 Mg ha−1, and the ratio of CWD mass to stand biomass varied from 0.06 to 0.13. The mean CWD mass input and loss rates were 4.81 Mg ha−1 yr−1 and 2.28 Mg ha−1 yr−1, respectively. A large heterogeneity of CWD mass, as represented by the spatial coefficient of variation (127.2%) and annual coefficient of variation (178.5%), might be inherent in the old-growth temperate forest, which consisted of large biomass trees. The decay rate constant, as estimated from the wood density change, was 0.049yr−1. However, the large variation of annual CWD mass input could cause the overestimation of decay rate constant (0.167 yr−1) as calculated from the ratio of CWD mass input to CWD mass. According to the CWD decay class classification, cl...