Figuerola Eva L M, Guerrero Leandro D, Türkowsky Dominique, Wall Luis G, Erijman Leonardo
Instituto de Investigaciones en Ingeniería Genética y Biología Molecular 'Dr Héctor N. Torres' (INGEBI-CONICET), Buenos Aires, Argentina.
Environ Microbiol. 2015 Mar;17(3):678-88. doi: 10.1111/1462-2920.12497. Epub 2014 Jun 2.
The goal of this study was to investigate the spatial turnover of soil bacterial communities in response to environmental changes introduced by the practices of soybean monoculture or crop rotations, relative to grassland soils. Amplicon sequencing of the 16S rRNA gene was used to analyse bacterial diversity in producer fields through three successive cropping cycles within one and a half years, across a regional scale of the Argentinean Pampas. Unlike local diversity, which was not significantly affected by land use type, agricultural management had a strong influence on β-diversity patterns. Distributions of pairwise distances between all soils samples under soybean monoculture had significantly lower β-diversity and narrower breadth compared with distributions of pairwise distances between soils managed with crop rotation. Interestingly, good agricultural practices had similar degree of β-diversity as natural grasslands. The higher phylogenetic relatedness of bacterial communities in soils under monoculture across the region was likely determined by the observed loss of endemic species, and affected mostly to phyla with low regional diversity, such as Acidobacteria, Verrucomicrobia and the candidates phyla SPAM and WS3. These results suggest that the implementation of good agricultural practices, including crop rotation, may be critical for the long-term conservation of soil biodiversity.
本研究的目的是调查相对于草地土壤，大豆单作或作物轮作实践所引入的环境变化对土壤细菌群落空间周转的影响。利用16S rRNA基因的扩增子测序，在一年半的时间内，通过三个连续的种植周期，在阿根廷潘帕斯草原的区域尺度上分析了生产田中的细菌多样性。与不受土地利用类型显著影响的局部多样性不同，农业管理对β多样性模式有强烈影响。与轮作管理的土壤之间的成对距离分布相比，大豆单作下所有土壤样品之间的成对距离分布具有显著更低的β多样性和更窄的范围。有趣的是，良好农业实践的β多样性程度与天然草地相似。整个区域单作土壤中细菌群落较高的系统发育相关性可能是由观察到的特有物种丧失所决定的，并且主要影响区域多样性较低的门类，如酸杆菌门、疣微菌门以及候选门类SPAM和WS3。这些结果表明，包括作物轮作在内的良好农业实践的实施对于土壤生物多样性的长期保护可能至关重要。
