Application of Biome-BGC model to simulate the carbon budget in a yellow cypress forest ecosystem at the Chi-Lan Mountain site

• Main Authors: Chia-Hsin Wu, 吳家欣
• Other Authors: Shih-Chieh Chang
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/43139620427734401030

碩士 === 國立東華大學 === 自然資源管理研究所 === 96 === An ecosystem process model, BIOME-BGC, was applied at the Chi-Lan Mountain (CLM) site for the simulation of biogeochemical cycles of a Chamaecyparis obtusa var. formosana forest ecosystem. The daily meteorological data of the site from 2004 to 2007 were applied repeatedly to the whole simulation period. 13 of the 34 ecophysiological parameters were taken from the results of previous studies at the site, while the rest of the parameters were taken directly from the default values of the model. The sensitivity analysis showed that the ecophysiological parameters that are most sensitive at the site were those related to carbon and nitrogen allocation. On the contrary, the water cycle-related parameters had less influences on GPP. The present biogeochemical cycles of the site were simulated using a sequence of simulations including system spin-up, 100 years of industrialized atmospheric conditions, 90% harvest of the original forest, and 40 years of growth of the regenerated forest. The ecosystem stayed at a condition of carbon-neutral for very long time period and after the harvest practice, the ecosystem became a strong carbon source which lasted for 23 years. At present, the ecosystem GPP, NPP, and NEP was 2.97, 0.89, and 0.33 kg C m-2 yr-1, respectively. The simulated carbon budget showed no difference when the fog deposition was removed from the total precipitation. A modification of the model to account for the effects of fog is necessary for this site. Furthermore, the simulated soil respiration overestimated the measurement data by far. A limitation of soil respiration under wet hydrological regime should be added to the model.