亚热带3种森林类型土壤微生物碳、氮生物量特征比较

为了比较不同森林类型土壤微生物数量和生物量的差异特征,揭示不同森林类型对微生物数量和生物量碳、氮的影响,采用稀释平板法和氯仿熏蒸浸提法,研究了湖南省长沙市天际岭国家森林植物园樟树人工林、马尾松人工林、樟树-马尾松混交林土壤微生物数量、碳氮生物量特征。结果表明:(1)樟树林、混交林和马尾松林中的土壤微生物总数量为樟树林>混交林>马尾松林,均呈显著差异(P<0.05);(2)林型对土壤微生物数量和比例有显著的影响。各类土壤微生物比例特征为:细菌为樟树林>马尾松林>混交林,真菌为混交林>马尾松>樟树林,放线菌为混交林>马尾松>樟树林;(3)3种林型土壤微生物生物量碳的特征为马尾松林>混交林>樟树林,其平均含量分别为543.01、421.48、370.95mg/kg;微生物生物量氮特征则为:樟树林>马尾松林>混交林,平均含量分别为37.28mg/kg、23.20mg/kg、15.12mg/kg。土壤微生物生物量碳、氮与土壤有机碳、全氮呈显著线性相关,与土壤水分相关关系不显著,土壤有机质是影响土壤微生物生物量的重要因素。

The Biomass Comparison of Soil Microbial Carbon and Nitrogen of 3 Kinds of Forest Types in Subtropics

In order to research the characteristics of different types of forest soil microorganism quantity and biomass in the global climate characteristics, to reveal the different forest types on microbial number and biomass carbon, nitrogen effect, the author used the method of chloroform fumigation extraction and dilution plate on camphor forest plantations, pine plantations and camphor-artificial pine mixed forest with soil microbes, biomass and distribution of carbon and nitrogen in Forest Botanical Garden, Changsha, Hunan. The results showed that： （1） camphor forest, mixed forest and pine forest, the total number of microbial camphor forestmixed forestpine forest, showed a significant difference （P0.05）; （2） Forest type had significant different impact on soil microbial quantity and proportion. Various types of microbial characteristics were as follows： bacteria was： camphor forestpine forestmixed forest; fungus was： mixed forestpine forestcamphor forest; actinomycetes was： mixed forestpine forestcamphor forest; （3） 3 forests in soil microbial biomass carbon was characterized by pine forestmixed forestcamphor forest, the average contents were 543.01 mg/kg, 421.48 mg/kg, 370.95 mg/kg; characteristics of microbial biomass nitrogen was： camphor forestpine forest mixed forest, the average content of 37.28 mg/kg, 23.20 mg/kg, 15.12 mg/kg. Microbial biomass carbon and nitrogen and soil organic carbon, total nitrogen was significantly positively correlated with soil moisture was no significant correlation between soil organic matter affect, soil microbial biomass was an important factor.