雷州林业局桉树人工林地土壤微生物的分布规律

The Distribution Law of Soil Microbes in Eucalyptus Plantations of Leizhou Forestry Bureau

对雷州林业局3种不同立地条件的6个桉树人工林地的土壤微生物的数量及其类群的分布规律进行了研究.结果表明:不同桉树林地的土壤微生物数量有差异,其数量与类群主要集中在0～20cm的表土层中,随着土层加深,其数量迅速减少;在深度为0～60cm的土层中,同一类群的微生物数量变化范围较大,其中好气性细菌数量为2.46×105～6.48×105个/g,厌气性细菌为1.14×103～8.8×103个/g,自生固氮菌为1.3×102～3.01×104个/g,放线菌为8.6×103～2.99×104个/g,真菌为6.6×103～2.435×105个/g,1号样地微生物数量最多,达2.45×106个/g,说明混交林中微生物数量较为丰富.

To find out the distribution law of soil microbes in Eucalyptus plantations in Forestry Bureau of Leizhou,the soil sample of six Eucalyptus plantations in three different sites of Leizhou Forestry Bureau were sampled and analysed,and the amount and group distribution of soil microbes in Eucalyptus plantations were analysed.The results showed that there were differences in the amount of soil microbes in different Eucalyptus plantations,and the amount and group of soil microbes were mainly concentrated in the 0～20 cm soil layer,and their quantity rapidly decreased with the increase of soil depth;The numbers of soil microbes of the same group varied greatly in soil with a depth of 0～60 cm,among which aerobic bacteria was 2.46×10~5～6.48×10~5 cell·g^(-1),anaerobe 1.14×10~3～(8.8)×10~3 cell·g^(-1),nitrogen fixing bacteria 1.3×10~2～3.01×10~4 cell·g^(-1),actinomyces 8.6×10~3～2.99×10~4 cell·g^(-1),and fungi 6.6×10~3～2.435×10~5 cell·g^(-1).The highest quantity of soil microbe was in No.1 plot,which reached 2.45×10~6 cell·g^(-1).It showed the numbers of soil microbes in mixed forest plantations were relatively plentiful.