云南红河流域麻疯树人工幼龄林碳密度与分配特征

用平均标准木法建立了云南红河流域麻疯树Jatropha curcas人工幼龄林不同器官生物量回归方程，并采用VARIO EL元素分析仪测定了麻疯树不同器官的含碳率，开展了麻疯树人工幼龄林生态系统植被生物量和土壤有机碳质量分数和碳密度研究。结果表明：用y = 25.005（D²H）^0.952方程测算出麻疯树人工幼龄林生态系统生物量为26.03 t·hm^－2。不同器官含碳率变幅范围为39.35%～56.74%，其中果实含碳率为56.74%，干枝含碳率为45.87%，根含碳率为45.12%，叶含碳率为39.35%，平均含碳率为47.27%。麻疯树幼龄林碳密度为5.54 t·hm^－2，灌木和草本植物碳密度为3.78 t·hm^－2，凋落物碳密度为2.59 t·hm^－2。麻疯树幼龄林土壤表层0 ～ 10 cm有机碳质量分数最大，为16.61 g·kg^－1。图2表3参25

Carbon density and allocation in young Jatropha curcas stands of the Honghe Region,Yunnan Province

Stand density of Jatropha curcas and the soil organic carbon content ratio of different organs compared to the whole plant in the Honghe Region,Yunnan Province was determined.Using the mean tree sampling method（20 m × 20 m） a regression equation for estimating biomass of different organs in young stands was established,and carbon content ratios were determined with a VARIO EL elemental analyzer.Then vegetative biomass and organic carbon allocation of the stand were calculated.Results showed that the best regression equation for calculating the biomass of young J.curcas was y = 25.005（D2H）0.952.Based on this equation and the sampling plots,biomass of the young forest was 26.03 t·hm-2.Carbon content ratios for the different organs ranged between 39.35%-56.74% with fruit = 56.74%,stems = 45.87%,roots = 45.12%,leaves = 39.35%,and the mean carbon content ratio for the whole plant = 47.3%.Also,carbon density was：J.curcas = 5.54 t·hm-2,shrub-grass = 3.78 t·hm-2,and litter = 2.59 t·hm-2.Additionally,the organic carbon content ratio was highest（16.61 g·kg-1） at the 0-10 cm soil layer depth.