Habitat selective factors influencing the structural composition and functional capacity of microbial communities in agricultural soils
Habitat selective factors influencing the structural composition and functional capacity of microbial communities in agricultural soils
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DOI：
10.1016/j.soilbio.2007.10.015
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发表时间：
2008-03
影响因子：
9.7
通讯作者：
S. Wakelin;L. Macdonald;S. Rogers;Adrienne L. Gregg;T. Bolger;J. Baldock
中科院分区：
文献类型：
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作者：
S. Wakelin;L. Macdonald;S. Rogers;Adrienne L. Gregg;T. Bolger;J. Baldock
确定了与澳大利亚农业土壤微生物群落组成和功能相关的关键物理化学因素。根据土壤的细菌和真菌群落结构(使用PCRDGGE)和通过评估潜在的分解代谢功能(MicroResp™)，对来自不同长期农业管理制度的七个田间地点的土壤进行了物理化学特征分析。土壤类型，而不是农业管理实践，是微生物群落结构和分解代谢功能的关键决定因素(P<；0.05)。通过多变量分析，土壤pH被确定为与生物多样性和有机底物利用剖面的变化有关的关键的生境选择土壤物理化学性质。土壤对不同C底物的分解能力与pH密切相关(ρ=0.604，P=0.001)。随着pH值的降低，常见低分子有机物(特别是半胱氨酸和天冬氨酸)的分解代谢降低，而赖氨酸和精氨酸的分解代谢增加。土壤微生物群循环常见有机化合物的能力的变化对酸化土壤中C和N的整体地球化学循环有一定的影响。土壤细菌群落的遗传结构与pH(ρ=0.722；P=0.001)和土壤真菌的遗传结构(ρ=0.323；P=0.006)密切相关。分解代谢功能与细菌群落结构的关系比真菌群落更密切。这项工作表明，土壤pH是土壤微生物多样性和功能的主要驱动力。因此，农业管理做法在这种背景下有选择地转移人口和功能。
Key physicochemical factors associated with microbial community composition and functions in Australian agricultural soils were identified. Soils from seven field sites, with varying long-term agricultural management regimes, were characterised physicochemically, on the basis of their bacterial and fungal community structures (using PCR-DGGE), and by assessing potential catabolic functions (MicroResp™). Soil type, rather than agricultural management practice, was the key determinant of microbial community structure and catabolic function (P<0.05). Following multivariate analysis, soil pH was identified as the key habitat-selective physicochemical soil property associated with variation in biological diversity and profiles of organic substrate utilisation. In particular, the capacity of soils to catabolise different C-substrates was closely correlated (ρ=0.604, P=0.001) to pH. With decreasing pH, the catabolism of common low molecular weight organic compounds (especially cysteine and aspartic acid) declined, however catabolism of two others (lysine and arginine) increased. Shifts in the capacity of soil microbiota to cycle common organic compounds have implications for overall geochemical cycling of C and N in acidifying soils. The genetic structure of the bacterial communities in soil strongly correlated with pH (ρ=0.722; P=0.001) and that of soil fungi with pH and % sand (ρ=0.323; P=0.006). Catabolic function was more closely associated with the structure of the bacterial than fungal communities. This work has shown that soil pH is a primary driver of microbial diversity and function in soil. Agricultural management practices thereby act to selectively shift populations and functions against this background.