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研究秦岭南坡东段8、25、35、42和61年生油松人工林碳、氮储量和分配格局.结果表明:油松人工林不同林龄乔木层碳、氮含量为441.40~526.21和3.13~3.99 g·kg-1,灌木层为426.06~447.25和10.62~12.45 g·kg-1,草本层为301.37~401.52和10.35~13.33 g·kg-1,枯落物层为382.83~424.71和8.69~11.90 g·kg-1,土壤层(0~100 cm)为1.51~18.17和0.29~1.45 g·kg-1.树干和树枝分别是乔木层的主要碳库和氮库,占乔木层碳储量的48.5%~62.7%和氮储量的39.2%~48.4%.林龄对生态系统碳、氮储量均有显著影响.生态系统碳储量随林龄增加而增加,35年时达最大值146.06 t·hm-2,成熟后碳储量有所下降.5个林龄段油松林生态系统氮储量的最大值为25年时的10.99 t·hm-2.植被层平均碳、氮储量分别为45.33t·hm-2和568.55 kg·hm-2,土壤层平均碳、氮储量分别为73.12和8.57 t·hm-2,且土壤层中碳、氮的积累具有明显的表层富集现象.研究区油松人工林生态系统碳、氮储量主要分布在土壤层,其次为乔木层.生态系统碳储量空间分配格局为:土壤层(64.1%)>乔木层(30.0%)>灌草层和枯落物层(5.9%),氮储量为土壤层(93.2%)>乔木层(5.3%)>灌草层和枯落物层(1.5%).
The results showed that the carbon and nitrogen contents of tree layers in Pinus tabulaeformis plantation varied from 441.40 to 526.21 and from 3.13 to 3.13 ~ 3.99 g · kg-1, and the shrub layer was 426.06 ~ 447.25 and 10.62 ~ 12.45 g · kg-1, the herb layer was 301.37 ~ 401.52 and 10.35 ~ 13.33 g · kg-1, litter layer was 382.83 ~ 424.71 and 8.69 ~ 11.90 g · kg-1, and the soil layer (0 ~ 100 cm) was 1.51-18.17 and 0.29-1.45 g · kg-1, respectively.The trunk and branch were the major carbon pools and nitrogen pools in the arbor, 48.5% -62.7% of nitrogen and 39.2% -48.4% of nitrogen.Ecological age had significant effects on ecosystem carbon and nitrogen reserves.The ecosystem carbon storage increased with age, reaching a maximum of 146.06 t · hm-2, and the carbon storage decreased after maturity.The maximum of nitrogen storage in Pinus tabulaeformis forest ecosystem was 10.99 t · hm-2 in 25 years.The average carbon and nitrogen reserves of vegetation layer were 45.33 t · hm-2 and 568.55 kg · hm-2 respectively, and the average carbon and nitrogen reserves in the soil layer were 73.12 and 8.57 t · hm-2, respectively, and the accumulation of carbon and nitrogen in the soil layer had obvious surface enrichment. Plantation ecosystem Carbon and nitrogen reserves mainly distributed in the soil layer, followed by the tree layer.The spatial distribution pattern of carbon storage in the ecosystem was as follows: soil layer (64.1%)> tree layer (30.0%)> shrub layer and litter layer (5.9% , And the nitrogen reserves were soil layer (93.2%)> arbor layer (5.3%)> shrub layer and litter layer (1.5%).