西藏南伊沟林芝云杉林生物量与生产力研究

Study on Biomass and Productivity of Picea likiangensis var. linzhiensis Forest in Nanyigou of Tibet

采用样地调查及标准样木收获法,研究西藏米林南伊沟成熟林芝云杉(Picea likiangensis var.linzhiensis)林乔木层、灌木层、草本层、死亡木、凋落物层的生物量与生产力及其分配规律。结果表明:林芝云杉林生态系统总的生物量为367.49 t·hm-2,其中乔木层生物量最高276.64 t·hm-2,占总生物量的75.28%,其次是凋落层的生物量40.65 t·hm-2,占总生物量的11.06%。在乔木层中,干材生物量201.23 t·hm-2(69.32%),皮25.53 t·hm-2(8.79%),枝17.80 t·hm-2(6.13%),叶3.33 t·hm-2(1.15%),根42.87 t·hm-2(14.61%)。随着树木的生长,干材生物量所占比例增大,而枝、叶的比例则减小。林芝云杉林生态系统生产力为10.65 t·hm-2·a-1,其中乔木层最高5.00 t·hm-2·a-1,占总生产力的46.94%,其次为凋落层3.40 t·hm-2·a-1,占总生产力31.94%。在乔木层中仍以树干生产力最大2.58 t·hm-2·a-1,依次为枝(0.89 t·hm-2·a-1)、叶(0.67 t·hm-2·a-1)、根(0.54t·hm-2·a-1)、皮(0.33 t·hm-2·a-1)。

Based on the data collected from a standard permanent plot of a primary Picea likiangensis var.linzhiensis forest in Milin Nanyigou in Tibet,the amount and distribution of biomass and productivity were studied by investigating and sample tree harvesting method.The results showed that the total vegetation biomass of P.likiangensis var.linzhiensis forest was 367.49 t·hm-2,of which overstory trees contributed the large proportion（75.28%） and amounted to 276.64 t·hm-2.The litter layer ranked the second with the biomass amount of 40.65 t·hm-2,accounted for 11.06% of the total biomass.In the overstory layer,the biomass was allocated as 201.23 t·hm-2（69.32%） for trunk,25.53 t·hm-2（8.79%） for bark,17.80 t·hm-2（6.13%） for branch,3.33 t·hm-2（1.15%） for leaf,and 42.87 t·hm-2（14.61%） for root.With the growth of trees,the biomass proportion of trunk and bark increased,while that of the branch and leaf decreased.The total vegetation productivity was 10.65 t·hm-2·a-1,of which overstory trees contributed a large proportion（46.94%） and amounted to 5.00 t·hm-2·a-1.The litter layer ranked the second with an amount of 3.40 t·hm-2·a-1 that accounted for 31.94% of the total proportion.In the overstory layer,the proportion was allocated as 2.58 t·hm-2·a-1 for trunk,0.89 t·hm-2·a-1 for branch,0.67 t·hm-2·a-1 for leaf,0.54 t·hm-2·a-1 for root and 0.33 t·hm-2·a-1 for bark.