柳州市三种人工林土壤有机碳储量的空间分布

采用野外调查、取样和实验室分析等方法,对柳州市杉木(Cunninghamia lanceolata)、马尾松(Pinus massoniana)和桉树(Eucalyptus sp.)人工林生态系统的土壤有机碳含量和有机碳储量及其分配进行了研究.结果表明,马尾松、杉木和桉树人工林土壤有机碳含量为3.2～12.6 g/kg,杉木人工林土壤有机碳含量最高,桉树人工林最小.马尾松、杉木和桉树人工林0～20 cm土层的土壤有机碳储量分别为26.25、30.09和17.05 t/hm2,分别占其土壤总有机碳储量的48.56％、44.70％和41.36％,成为土壤有机碳储量的主体,土壤的有机碳含量和有机碳储量均随着土层深度的增加而减少.土壤有机碳储量表现为杉木人工林(67.33 t/hm2)＞马尾松人工林(54.06 t/hm2)＞桉树人工林(41.22 t/hm2);马尾松人工林土壤有机碳储量表现为中龄林＞幼龄林＞过熟林＞成熟林;杉木中龄林的土壤有机碳储量大于成熟林,彼此间差异不显著;三年生的桉树人工林的土壤有机碳储量高于二年生和四年生的;杉木中龄林和成熟林的土壤有机碳储量分别高于马尾松中龄林和成熟林.

Spacial Distribution of Soil Organic Carbon Storage in Massion Pine,Chinese Fir and Eucalyptus Plantations in Liuzhou City

Using the research method of field investigation,soil sampling and laboratory analysis,the soil carbon content,storage and distribution in masson pine(Pinus massoniana),Chinese fir(Cunninghamia lanceolata) and eucalyptus(Eucalyptus sp.) plantation ecosystems in Liuzhou city,Guangxi province were studied.The results showed that the soil carbon content(percent of dry weight) in all plantations at different ages ranged from 3.2～12.6 g/kg.When considering the soil carbon content of all plantations,the highest value occurred in the Chinese fir plantation,while eucalyputs plantation displayed the lowest value.The carbon storage of 0~20 cm soil of masson pine,Chinese fir and eucalyptus plantations were 26.25,30.09 and 17.05 t/hm2 respectively,which accounted for 48.56%,44.70%,and 41.36% of the entire stored soil carbon within each ecosystem,and accounted for the majority in total carbon storage.The soil carbon content and storage within the masson pine,Chinese fir and eucalyptus plantations decreased with the soil depth.The soil carbon storage ranged from highest to lowest as Chinese fir(67.33 t/hm2) > masson pine(54.06 t/hm2) > eucalyptus(41.22 t/hm2).The order of soil carbon storage of masson pine in different age was middled-age > sappling > overmature > mature.The soil carbon storage of middle-age Chinese fir was higher than that of mature forest,the soil carbon storage of eucalyptus in 3 a was greater than that in 2 a and 4 a respectively.The soil carbon storages of middle-age and mature Chinese fir plantation were higher than that of middle-age and mature masson pine.