Carbon and Nitrogen Responses of Litterfall Components by NPK and PK Fertilizers in a Red Pine (Pinus densiflora S. et Z.) Stand

This study was conducted to determine the carbon (C) and nitrogen (N) response of litterfall components as affected by N addition in compound fertilizer in a Korean red pine (Pinus densiflora S. et Z.) stand in southern Korea. Litterfall in a mature red pine stand was collected for two years following compound fertilizer application (N3P4K1; P4K1) and no fertilization (control). The C concentration of litterfall components was not significantly (P > 0.05) different between the N3P4K1 and the control plots, whereas the N concentration of the litterfall components was significantly higher in the N3P4K1 plot than in the control plot. The N3P4K1 and P4K1 additions induced a lower C/N ratio of litterfall components compared with the control plot. Annual C and N fluxes via litterfall components were not affected by the N3P4K1 addition over the study period, except for reproduction litter. Annual N fluxes via reproduction litter were significantly higher in the N3P4K1 plot than in the control plot. Thus, the N3P4K1 and P4K1 additions could modify differently nutrient distribution of the forest floor and mineral soils in a red pine stand. These results indicate that N concentration and C/N ratio in litterfall components are more susceptible to fertilizer application than the C response in litterfall components