Weight Loss and Nutrients Dynamics during the Decomposition of Fine Roots

Weight loss, N and P dynamics during decomposition of fine roots (<2mm) of alder(Alnus japonica), oak (Quercus acutissima) and pitch pine(Pinus rigida) were studied for 33 months in Kongju, Korea. After 33 months, remaining weight of fine roots of alder, oak and pitch pine was 29.2%, 47.7% and 53.4% of the initial weight, respectively. The decomposition rate constant (k) for alder, oak and pitch pine was 0.448 $yr^1$, 0.269 $yr^1$, 0.228 $yr^1$, respectively. Initial concentration of N and P in fine roots was 10.32mg/g and 0.69mg/g for alder, 6.20mg/g and 0.37mg/g for oak and 7.26mg/g and 0.44mg/g for pitch pine, respectively. Initial concentration of N and P in alder were higher than those in oak and pitch pine. After 33 months, remaining N and P in fine roots was 39.5$\%$ and 31.8$\%$ for alder, 59.4$\%$ and 57.8$\%$ for oak, 63.0$\%$ and 83.4$\%$ for pitch pine, respectively. Decomposition rate and the rate of N released from decomposing fine roots was positively correlated with the initial N concentration of the fine roots.