摘要: |
【目的】研究不同林龄沙棘人工林土壤微生物多样性的差异,为沙棘林分的衰败机制研究奠定基础。【方法】采用BIOLOG-ECO微平板法,对不同林龄(8,13,18年生)沙棘人工林表层土(0~10 cm)微生物利用碳源的动力学特征和土壤微生物多样性进行研究,比较分析土壤微生物利用碳源能力、土壤微生物多样性与沙棘人工林林龄的相关性。【结果】18年生沙棘人工林表层土在短期内(培养24~60 h)对单一碳源底物的利用能力高于13和8年生沙棘林表层土,说明13和8年生沙棘人工林表层土中微生物生长的启动速度较慢,生长停滞期较长。随着林龄的延长,土壤微生物群落的Shannon指数(H′)、Simpson指数(D)和Mcintosh指数(U)的变化规律不同,13年生沙棘人工林表层土微生物群落的D、H′值均最大,但U值最小;8和18年生沙棘人工林表层土微生物群落的D、H′、U值差异很小。13年生沙棘人工林表层土微生物利用羧酸类化合物的能力,在培养72 h后相对于8和18年生沙棘人工林均有明显提高;8和18年生沙棘人工林表层土微生物利用醣类化合物的能力,在培养24~144 h时相对于13年生沙棘人工林有明显优势。在其他化合物的利用能力上,8,13和18年生沙棘人工林表层土微生物未表现出明显的差异。只有18年生沙棘人工林表层土在主成分1上可以与13年生沙棘人工林表层土很好地分离,其他林龄沙棘林表层土在主成分1,2,3,4上均未实现分离。【结论】沙棘林的微生物多样性与其林龄存在一定关系。 |
关键词: 沙棘林 林龄 表层土 微生物功能多样性 |
DOI: |
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基金项目:国家“十一五”林业科技支撑计划项目(2006BAD03A1207) |
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Study on soil microbial diversity of seabuckthorn forest |
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Abstract: |
【Objective】The comparative study on soil microbial diversity in seabuckthorn plantations of different ages is to provide theoretical basis for the decay mechanism of seabuckthorn forest.【Method】BIOLOG-ECO micro-plate methodology was taken to study dynamic characteristics of micro organisms using carbon and soil microbial diversity of seabuckthorn plantations in different ages(8,13,18-year)topsoil(0-10 cm),a comparative analysis of the relationship among ability of use carbon,soil microbial diversity and seabuckthorn plantation’s age.【Result】 In the short term(incubation 24-60 h),a single carbon substrate utilization capacity of 18-year topsoil of seabuckthorn plantations is more than that of 13-year and 8-year topsoil,indicating that 13-year,8-year microbial growth of surface soil starts slowly,and microbial stagnation lasts longer;With the extension of the stand age,the Shannon index(H′),Simpson index(D) and Mcintosh index(U) of soil microbial communities shows a different regularity.The D index and the H′ index of 13 year topsoil of seabuckthorn plantations microbial communities are the largest,but the U index is the smallest,the D index,H′ index,U index of 8 year,18-year topsoil of seabuckthorn plantations microbial communities make little difference;Compared to 8-year and 18-year the capable of using carboxylic acids of topsoil micro-organisms,13-year seabuckthorn plantations after 72 h culture has a clear advantage.8,18-year seabuckthorn plantations on topsoil microorganisms in the use of capacity of sugar compounds form 24 h to 144 h has an obvious advantage than 13 year.The capacity of using other compounds on topsoil microorganisms of seabuckthorn plantation in different ages doesn’t show a great difference;Only 18-year on the main component PCA1 of topsoil has a good separation from 13-year,others are not met.【Conclusion】 Difference in microbial diversity has a certain relationship with seabuckthorn’s ages. |
Key words: seabuckthorn forest stand age topsoil microbial functional diversity |