为了探究不同林龄油松根际与非根际土壤微生物群落多样性及其与土壤环境因子之间的关系,利用Illumina-MiSeq高通量测序技术对不同林龄油松根际与非根际土壤中细菌的16SrDNA基因V3—V4区片段和真菌18SrDNA基因V4区片段进行测序,为油松的人工培育林提供有益借鉴和参考。结果 表明:(1)油松根际土壤pH值显著低于非根际(p<0.05),根际土壤有机碳、全氮、有效氮和有效磷均显著高于非根际(p<0.05),土壤中根际和非根际有机碳、全氮、有效磷和有效钾含量呈一致的变化趋势,随着油松林龄的增长表现出先增加后降低趋势,在成熟林阶段达到最大值。(2)土壤中根际土壤酶活性(蔗糖酶活性、碱性磷酸酶活性、脲酶活性、过氧化氢酶活性)显著高于非根际,随着油松林龄的增长表现出先增加后降低趋势,在成熟林阶段达到最大值,过熟林有所降低。(3)油松根际土壤细菌和真菌多样性指数均高于非根际,其中随着油松林龄的增长表现出先增加后降低趋势,丰富度指数、Shannon-Wiener指数、ACE、Chao 1指数均显著高于非根际(p<0.05); 而根际土壤细菌和真菌覆盖度、均匀度和Simpson指数指数与非根际差异并不显著(p>0.05)。(4)主坐标分析(PCoA)分析表明,油松土壤根际和非根际细菌和真菌群落具有很好的相似性,并且根际和非根际细菌群落产生明显的分离效应。(5)冗余分析显示,土壤环境因子对油松土壤细菌和真菌多样性有显著影响。其中对土壤细菌和真菌多样性影响较大的有SOC和TN,而pH值对土壤细菌和真菌多样性影响为负。
Microbial diversity and its influencing factors in rhizosphere and non-rhizosphere in the stands of Pinus tabulaeformis with different ages were studied by using Illumina-MiSeq high-throughput sequencing technologies to measure sequences of 16srDNA gene segments of V3—V4 area of bacteria and 18srDNA gene segments of V4 area of fungi, in order to provide useful management for Pinus tabulaeformis plantation. The results showed that:(1)pH value of the rhizosphere soil value of Pinus tabulaeformis was significantly lower than that of the non-rhizosphere(p<0.05), soil organic carbon, total nitrogen, available nitrogen and available phosphorus in rhizosphere were significantly higher than those of the non-rhizosphere(p<0.05), soil organic carbon, total nitrogen, available phosphorus and available potassium contents in rhizosphere and non-rhizosphere showed the consistent change trend, reaching to the maximum values in the mature forest;(2)activity of soil invertase, alkaline phosphatase, urease and catalase in rhizosphere were significantly higher than the non-rhizosphere, soil enzyme activities in rhizosphere and non-rhizosphere showed the consistent change trend, reaching to the maximum values in the mature forest and decreasing in the aged forest;(3)the diversity indexes of bacteria and fungi in the rhizosphere of Pinus tabulaeformis was higher than those in the non-rhizosphere; the richness index, shannon-wiener index, ACE index and Chao 1 index in rhizosphere were significantly higher than those in the non-rhizosphere with the growth of the age of Pinus tabulaeformis; however, there were no significant differences in the coverage, uniformity and Simpson index between the rhizosphere and the non-rhizosphere soil (p>0.05);(4)PCoA analysis showed that the bacterial and fungal communities in rhizosphere and non-rhizosphere of stands of Pinus tabulaeformis had the higher similarity, and the communities in rhizosphere and non-rhizosphere bacterial produced obvious separation effects;(5)redundancy analysis showed that the nine soil environmental factors explained the total characteristic values of 86% bacteria and 82% fungi, respectively, indicating that the soil environmental factors had a significant impact on the diversity of bacteria and fungi in soils of stands of Pinus tabulaeformis, soil organic carbon and total nitrogen had a great impact on soil bacterial and fungal diversity, while pH value had the negative impact on soil bacterial and fungal diversity.
