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在省级尺度上分析不同林龄杉木生物量数据,以探索江西省杉木人工林生物量的动态分配格局及其准确估算方法。结果表明:江西省杉木人工林生物量变化范围为55.64~165.22 t/hm~2,其乔木层生物量占94.2%以上。杉木林及其乔木层生物量随林龄先增加后略微下降,而各林龄的灌木层、草本层和凋落物层生物量均没有显著差异。幼龄林、近熟林、成熟林各组分生物量大小排序均为乔木层>凋落物层>灌木层>草本层,而在中龄林和过熟林中则为乔木层>凋落物层>草本层>灌木层。幼龄林各器官生物量大小排序为树干>叶>根>枝,而其他林龄中的排序均为树干>根>枝>叶。以胸径(D)为单变量的杉木单株生物量(W)模型(W=0.266D~(2.069))及以胸径(D)和树高(H)为变量的模型(W=0.046 9(D~2H)~(0.906 4))预测值小于测量值,且预测精度R~2均为0.84,其精度和预测能力均低于以胸径、林龄(A)、密度(N)为自变量的生物量模型(W=11.497D~(1.847)A~(0.082)N~(-0.478))。
In order to explore the dynamic distribution pattern of biomass of Cunninghamia lanceolata plantations in Jiangxi Province and its accurate estimation method, the biomass data of different ages were analyzed at the provincial scale. The results showed that the biomass of Cunninghamia lanceolata plantations ranged from 55.64 to 165.22 t / hm ~ 2 in Jiangxi Province, accounting for 94.2% of the biomass of tree layers. The biomass of Cunninghamia lanceolata plantation and its arbor layer decreased slightly with increasing forest age, but there was no significant difference in the biomass of shrub layer, herb layer and litter layer in each age. The order of biomass of the young, near-mature and mature forests was in the order of arbor layer> litter layer> shrub layer> herb layer, while in the middle-aged forest and over-mature forest, arbor layer> litter layer > Herb layer> shrub layer. The order of the biomass of young organs was stem> leaf> root> branch, while the others were trunk> root> branch> leaf. (W = 0.266D ~ (2.069)) and DBH (D) and tree height (H) as model variables (W = 0.046 9 D ~ 2H) ~ (0.906 4), the predicted value is less than the measured value, and the prediction accuracy R ~ 2 is 0.84, the accuracy and the predictive ability are lower than those with DBH, AGA and N as independent variables The biomass model (W = 11.497D ~ (1.847) A ~ (0.082) N ~ (-0.478)).