东北地区陆地碳循环平衡模拟分析

Simulation Analyses of Terrestrial Carbon Cycle Balance Model in Northeast China

依据陆地碳循环过程 ,基于多年平均气候数据建立陆地碳循环平衡模型 ,并模拟了陆地碳循环平衡状态下 ,我国东北地区陆地碳循环的主要碳通量 ,其中 ,东北地区植被潜在净第一性生产力 (NPP)估算为 5.1 6× 1 0 8t C/a,NPP的分布由于受纬度地带性、经度地带性等植被、气候和地形因素的综合影响 ,总体呈现从东南到西北递减的趋势 ,东北地区植被潜在年凋落物速率为 5.1 6× 1 0 8t C/a,凋落物年矿化分解速率为 3.61× 1 0 8t C/a,凋落物年腐殖化速率为 1 .55× 1 0 8t C/a,凋落物碳库为 4.67× 1 0 8t C,土壤有机碳年分解速率为 1 .55× 1 0 8t C/a。通过探讨各主要碳库和碳通量的大小以及空间分布特点 ,描绘了东北地区陆地碳循环平衡状态的空间格局。研究表明 NPP、凋落物碳库和土壤碳库的分解速率对于整个陆地碳循环过程是很重要的。

We have estimated vegetation carbon and soil organic carbon based on the fourth national forest inventory with 121 plots and second national soil survey with 388 soil profiles. Our estimate indicates that the amount of vegetation and soil organic carbon for Northeast China are 2.81×10 15 gC and 26.43×10 15 gC respectively, and that the densities of vegetation and soil organic carbon are 2.27 kgC/m 2 and 21.27 kgC/m 2 respectively. The eastern and northern parts of the region have much higher carbon storage than the rest of the region. Meanwhile, based on climate material, the simplified Terrestrial Carbon Cycle Balance (TCCB) model was established,which is semi mechanism and semi statistics. Through the TCCB model, this paper calculated the litter carbon pool, NPP, carbon fluxes and described the spatial characters of carbon pools and fluxes in Northeast China. Based on the TCCB model simulation, under current climate conditions, NPP in Northeast China is 5.16×10 8 tC/a, vegetation litterfall rate is 5.16×10 8 tC/a, litter mineralization rate is 3.61×10 8 tC/a, soil organic inputting rate is 1.55×10 8 tC/a, the litter carbon pool is 4.67×10 8 tC, and the soil decomposition rate is 1.55×10 8 tC/a. The carbon budget was also analyzed based on the estimates of carbon pools and fluxes. The spatial distribution of carbon pools and carbon fluxes in different compartments of terrestrial ecosystem was depicted with map respectively in Northeast China.