【摘要】 以普洱市思茅区清水河13年生西南桦人工林、高阿丁枫人工林、思茅松人工林及思茅松天然林为研究对象,对林分土层0～50 cm土壤有机碳含量及密度进行调查分析。结果表明:(1)土壤有机碳含量、可溶性有机碳含量和土壤微生物量碳含量在4种林分中均呈随土层深度增加而递减的变化趋势,0～50 cm土层土壤有机碳含量为高阿丁枫人工林>西南桦人工林>思茅松人工林>思茅松天然林,土壤可溶性碳含量为高阿丁枫人工林最大,西南桦人工林最小;土壤微生物量碳主要集中于土壤表层,西南桦人工林土壤微生物量碳含量最高。(2)土壤可溶性碳占土壤有机碳的比值范围为0.32%～1.25%,3种人工林土壤表层微生物量碳占土壤有机碳的比值均大于思茅松天然林,3种人工林均处于碳的积累阶段。(3)0～50 cm土层土壤有机碳密度以思茅松人工林最大,达到85.79 t/hm2;其次为西南桦人工林、高阿丁枫人工林,思茅松天然林最低,为61.36 t/hm2。(4)土壤可溶性碳、土壤微生物量碳与土壤有机碳含量成显著的正相关关系,土壤有机碳和可溶性碳与土壤容重成显著的负相关关系。更多还原

【Abstract】 Soil total organic carbon content and density in the depth of 0 ～ 50 cm of four forest stands,namely Betula alnoides plantation,Altingia excelsa plantation,Pinus kesiya var.langbianensis plantation and Pinus kesiya var.langbianensis natural forest,were studied.The results showed that :(1) Soil total organic carbon(TOC) content,dissolved organic carbon(DOC),soil microbial biomass carbon(MBC) in 4 stands decreased with the increase of soil depth,the order of TOC content was A.excelsa plantation > B.alnoides plantation > P.kesiya var.langbianensis plantation > P.kesiya var.langbianensis natural forest,DOC was maximum in A.excelsa plantation and minimum in B.alnoides plantation.Soil MBC mainly concentrated on the top soil and the maximum was in B.alnoides plantation.(2) DOC accounted for 0.32 % ～ 1.25 % of TOC,the propertions of MBC in TOC of 3 plantations were highere than that in naural forest;(3) The highest organic carbon density in 0 ～ 50 cm depth was 85.79 t / hm2 in P.kesiya var.langbianensis plantation,followed by A.excelsa plantation and B.alnoides plantation,the lowest was 61.36 t / hm2 in P.kesiya var.langbianensis natural forest;(4) DOC,MBC were positively corre-lated with TOC,TOC and DOC were negatively correlated with soil bulk density.更多还原