Simulating the soil carbon dynamics of Pinus densiflora forests in central Korea

Abstract

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=0.900.98, slope = 0.950.98). 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. The estimated total SOC stock was higher in the scenario of less frequent clear-cut, while its annual increment was higher in the scenario of more frequent clear-cut in the past. The KFSC will be useful, especially for simulating soil carbon dynamics in forests with scarce information, and has the potential to estimate soil carbon dynamics at a national scale by incorporating with geographical information system.