采用现场实测的方法,对湖南沅陵林区保存的天然次生檫木枫香混交林生物量和生产力进行了研究.结果表明:混交林中各树种株数不均匀,单株生物量以檫木最大,为863.10 kg,光皮桦145.40 kg次之,锥栗21.00kg最小；林分中乔木层生物量为218.29 t/hm2,其檫木生物量最高,为90.63 t/hm2,占乔木层生物量41.5％,其次为枫香29.26 t/hm2,占13.4％,南酸枣最低,为3.38t/hm2,仅占1.5％；混交林林分生物量为253.55 t/hm2,其中乔木层占林分总生物量的86.0％,灌木层占8.2％,死地被物层占5.7％,草本层仅占0.1％；混交林中乔木层的生产力为13.53 t/(hm2·a),其中以树叶生产力最高,为8.28 t/(hm2·a),占61.20％,树干2.84 t/(hm2·a),占20.99％,树枝1.24 t/(hm2·a),占9.17％,树根0.75 t/(hm2·a),占5.54％,树皮0.42t/(hm2·a),仅占3.10％,树叶生产力高,每年凋落于林地,对维护林地生产力极为有利.研究结果可为科学保护和合理开发利用及可持续经营管理天然次生林,为全球气候变化及碳循环研究提供科学依据.%Biomass and productivity of natural secondary Sassafrastzumu and Liquidambar formosana mixed forest were investigated in Yuanling county. The results show that the number of trees was not homogeneous for each tree species in mixed forest, and mean individual tree biomass of Sassafras tzumu(863. 10 kg) was largest, the next was Betula LuminiferaiUS. 40 kg) , and the smallest was Castanea henryi(.21. 00 kg). The arbor layer biomass in mixed forest was 218. 29 t/hm2, in which the highest was biomass of Sassafras tzumu(,90. 63 t/hm2) that accounted for 41. 5% of the arbor layer biomass, the next was Liquidambar forynosana(29. 26 t · hm-2) that accounted for 13. 4% of the arbor layer biomass, and the least was Choerospondias axillaria(3. 38 t · hm-2) that only accounted for 1. 5%. Stand biomass in mixed forest was 253. 55 t/hm2, in which biomass in the arbor, shrub, dead vegetation and herbaceous layer accounted for 86. 0%, 8. 2%, 5. 7%, and 0. 1% of the total stand biomass,respectively. The arbor layer productivity was 13. 53 t/(hm2 · a), in which the productivity of leaf, stem, branch, root and bark was 8. 28, 2. 84, 1. 24, 0. 75 and 0. 42 t/(hm2 · a) that accounted for 61. 20%, 20. 99%, 9. 17%, 5. 54% and 3.10%, and leaf productivity was highest and leaves fall down in woodlands every year, which was important to maintain woodland productivity. The results provided scientific references for sustainable management of natural secondary forest and global climate change and carbon cycle research.
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