不同间伐强度对杉木人工林碳储量及其分配的影响

The effect of carbon storage and its allocation in Cunninghamia lanceolata plantations with different thinning intensities

间伐改变了林分环境,影响林木生长及碳储量,准确评估不同间伐强度对杉木人工林生物量及碳储量的影响对碳汇林业的发展具有重要意义。2013年,以中国林业科学研究院热带林业实验中心1992年造林并于2005年实施3种不同间伐强度(74%:H、50%:M和34%:L)的杉木人工林为研究对象,样地内每木检尺,实测样木生物量,并结合杉木群落各组分含碳率的实测值,对杉木人工林的生物量和碳储量进行估算,结果表明:H(74%)显著增加了林木的胸径(P<0.01),分别比M(50%)、L(34%)和CK(0%)增加了13.65%、20.74%和18.37%。3种间伐强度之间树高差异均不显著,而CK的树高均大于3种间伐强度的树高,分别比H、M和L增加了6.64%、15.73%和16.70%。与对照相比,H显著增加了林木的单株生物量(P<0.01)。对照林地乔木层的碳储量均显著高于其他3种间伐强度的乔木层碳储量(P<0.05),而乔木层各器官碳储量大小顺序为:树干>树枝>树根>树皮>树叶;3种间伐强度和对照处理杉木人工林之间的生态系统碳储量差异性不显著(P>0.05),其中乔木层和土壤层为主要碳库,两者所占总的碳储量超过生态系统总的碳储量的97.62%。

The stand environment, tree growth, and carbon storage of plantations could be affected assess the dynamics of the forest ecosystem carbon pool, it is important to determine the changes by thinning. Thus, to of carbon storage in plantations after thinning.In 2013, the biomass, and carbon storage and allocation of Cunninghamia lanceolata plantations with different thinning intensities （i.e., H. 74%, M. 50%, and L. 34%） were studied using a biomass survey at the Experiment Center of Tropical Forestry of the Chinese Academy of Forestry. The results showed that the diameter at breast height （DBH） of H was significantly higher （P〈0.01） than M, L, and CK （0%）, which increased by 13.65%, 20.74%,and 18.37%, respectively. There was no difference in the height of trees between the three thinning intensities; however, the height of trees in CK （0%） plots was higher than those in plots of the three thinning intensities, which increased by 6.64%, 15.73%, and 16.70%, for H, M, and L, respectively. The individual biomass with H was significantly higher （ P〈0.01 ） than that for M, L, and CK. The carbon storage of the arbor layer in CK was significantly higher （P〈0.05） than that in the three thinning intensities, and the carbon storage in different organs was in the order： stem〉branch〉root〉bark〉 leaf. There was no difference between the carbon storage of C. lanceolata plantation ecosystems with the three thinning intensities and CK plots. The arbor and soil layers were the main carbon pools, accounting for more than 97.62%.