Dong Ling-Bo, Chen Guan-Mou, Lin Xue-Ying, Liu Zhao-Gang
Ministry of Education Key Laboratory of Sustainable Forest Ecosystem Management, School of Forestry, Northeast Forestry University, Harbin 150040, China.
Ying Yong Sheng Tai Xue Bao. 2022 Oct;33(10):2653-2662. doi: 10.13287/j.1001-9332.202210.009.
Based on datasets from plot survey and bibliographic of plantations in Maoer Mountain, the COFIX model was used to quantitatively simulate the effects of different rotations (30, 40, 50, 60 years), site indices (12, 16, 20 m), and initial densities (2500, 3333, 4444 trees·hm) on the stand level carbon flows among different carbon pools (, biomass carbon pool, soil carbon pool, and product carbon pool). The results showed that the COFIX model had high reliability for simulating the processes of plantation, with the average relative errors of stand biomass and volume between analog and measured values being 6.4% and 3.7%. Under the baseline conditions of initial density of 3333 trees·hm, site index of 16 m and rotation of 40 years, the carbon stock of total and sub-pool of plantation changed periodically with rotation. The total stand carbon stock and volume for plantation increased with the extension of rotation, the improvement of site index, and the increase of initial density. The stand carbon stock and volume would be increased by 12.2% and 31.2%, 36.7% and 67.8%, respectively, when the reference rotation was correspondingly extended by 10 and 20 years. However, if the reference rotation was shortened by 10 years, stand carbon stock and volume would be correspondingly decreased by 20.9% and 40.4%, respectively. When the initial density was set as 3333 and 4444 trees·hm, stand carbon stock and volume were increased by 27.8% and 50.9%, 27.4% and 49.1%, respectively. When the site index was under the range of 12 to 20 m, stand carbon stock and volume could be increased by 36.0% and 40.3%, 39.3% and 44.2%, respectively, with each increase of 4 m in site index. During one rotation, 271.57 t C per hectare could be fixed into plantation. At the end round of the rotation, 27.47 and 56.75 t C were transferred to soil and wood product carbon pools. Therefore, when the site condition was good, the management model with a higher initial density (4444 trees·hm) and longer rotation (60 years) would be more beneficial to maximizing the carbon sink and timber benefits of plantation.
基于猫儿山人工林样地调查和文献数据集，采用COFIX模型定量模拟不同轮伐期（30、40、50、60年）、立地指数（12、16、20米）和初始密度（2500、3333、4444株·公顷）对不同碳库（生物量碳库、土壤碳库和产品碳库）间林分水平碳流的影响。结果表明，COFIX模型在模拟人工林过程方面具有较高可靠性，林分生物量和蓄积量模拟值与实测值的平均相对误差分别为6.4%和3.7%。在初始密度3333株·公顷、立地指数16米和轮伐期40年的基线条件下，人工林总碳库和子碳库的碳储量随轮伐期呈周期性变化。人工林林分总碳储量和蓄积量随轮伐期延长、立地指数提高和初始密度增加而增加。当参考轮伐期相应延长10年和20年时，林分碳储量和蓄积量将分别增加12.2%和31.2%、36.7%和67.8%。然而，如果参考轮伐期缩短10年，林分碳储量和蓄积量将分别相应减少20.9%和40.4%。当初始密度设为3333和4444株·公顷时，林分碳储量和蓄积量分别增加27.8%和50.9%、27.4%和49.1%。当立地指数在12至20米范围内时，立地指数每增加4米，林分碳储量和蓄积量可分别增加36.0%和40.3%、39.3%和44.2%。在一个轮伐期内，每公顷人工林可固碳271.57吨碳。在轮伐期末，27.47吨碳和56.75吨碳分别转移到土壤和木材产品碳库。因此，在立地条件良好时采用较高初始密度（4444株·公顷）和较长轮伐期（60年）的经营模式更有利于最大化人工林的碳汇和木材效益。
