海南岛典型地区桉树人工林生态系统碳、氮储量及其分配格局

朱美玲　王旭　王帅　王文蕾　邹耀进　梁卿雅

摘 要 对海南岛儋州、屯昌和琼海3个地区的2、4和6龄桉树人工林进行调查，研究桉树人工林生态系统碳、氮储量的变化动态及分配格局。结果表明：不同林龄桉树人工林林下植被碳含量为430.5～439.6 g/kg，氮含量为13.3～15.2 g/kg；枯落物碳含量为427.7～475.2 g/kg，氮含量为16.2～18.9 g/kg。0～100 cm土层碳含量为3.11～47.99 g/kg，氮含量为0.34～2.34 g/kg。土壤碳含量和氮含量均有随土壤深度的增加而减小，其中0～10 cm土层的碳含量和氮含量最高。3个地区桉树人工林生态系统总碳储量分别为83.98、158.13和189.58 t/hm2，总氮储量分别为9.61、11.59、和13.08 t/hm2。桉树人工林生态系统碳、氮储量均随林龄的增加而增加，琼海地区碳、氮储量均高于儋州和屯昌。土壤层是桉树人工林主要的碳库和氮库，碳、氮储量分别占生态系统的54.93%～98.54%和94.53%～99.65%，其次是乔木层。就3个地区林龄平均水平相比而言，土壤层碳占生态系统的比例大小为：琼海>屯昌>儋州，而乔木层碳占系统的比例大小为：儋州>屯昌>琼海。土壤层氮占生态系统的比例大小为：屯昌>琼海>儋州。

关键词 桉树人工林；碳储量；氮储量；林龄；分配格局

中图分类号 S718.5 文献标识码 A

Abstract The 2， 4 and 6 years old Eucalyptus plantations in Danzhou，Tunchang and Qionghai of Hainan Island were investigated to study the dynamics and allocation patterns of carbon and nitrogen storage. The results showed that the ranges of carbon and nitrogen contents were 430.5-439.6 g/kg and 13.3-15.2 g/kg in the undergrowth layer of different age Eucalyptus plantations， 427.7-475.2 g/kg and 16.2～18.9 g/kg in the litter layer， 3.11-47.99 g/kg and 0.34-2.34 g/kg in the 0～100 cm soil layer. The soil carbon and nitrogen content decreased with the soil depth. The total carbon storage of Eucalyptus plantation in the three regions was 83.98， 158.13 and 189.58 t/hm2； and the total nitrogen storage was 9.61， 11.59 and 13.08 t/hm2. The total carbon and nitrogen storage in Eucalyptus plantation increased with the increase of forest age， and the carbon and nitrogen storage in Qionghai were higher than those of Danzhou and Tunchang. The soil layer was the major carbon pool and nitrogen pool in Eucalyptus plantation ecosystem， accounting for 54.93%～98.54% and 94.53%～99.65%， the second was the tree layer. In terms of the average forest age in the three regions， the size of carbon storage of soil layer accounted for the proportion of ecological system was： Qionghai>TunChang>Danzhou， while the tree layer： Danzhou>TunChang>Qionghai. The size of nitrogen storage of soil layer accounted for the proportion of ecological system was： TunChang>Qionghai>Danzhou.

Key words Eucalyptus plantation；Carbon storage；Nitrogen storage；Forest age；Allocation pattern

doi 10.3969/j.issn.1000-2561.2015.11.005

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