Submitted to: Ecological Society of America Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 8/7/2011
Publication Date: 8/12/2011
Citation: Davinic, M., Moore-Kucera, J., Fultz, L., Dowd, S., Acosta Martinez, V., Cox, S.B., Allen, V.G. 2011. Pyrosequencing-based assessment of soil bacterial communities within soil aggregates: Linking structure to C storage [abstract]. Ecological Society of America Annual Meeting. August 7-12, 2011. Austin, TX. Abstract No. 31444. Interpretive Summary:
Technical Abstract: Alterations in soil structural properties created by agricultural management practices have a significant influence on soil aggregation, which manages the chemical and physical heterogeneity of soil properties, and, consequently, the distribution of microorganisms and their activity among aggregates of different sizes. Despite the essential role of soil microbial communities in C sequestration, green house gas emission and formation of soil aggregates, attempts to determinemicrobial community distribution within various size aggregates have received little attention. This study evaluated bacterial diversity of different aggregate size classes of soil samples using bacterial tag-encoded FLX amplicon pyrosequencing of the 16S rDNA gene. Soil samples (clay loam, 38% clay, pH of 7.5) were collected from the 0-5cm depth from a long-term (8 years) study with 5 integrated crop and livestock (beef cattle) systems. A wet-sieving fractionation method on field-moist soil was used to separate the bulk soil into macroaggregates (>250 um), microaggregates (53-250 um) and silt+clay (< 53 um). Distance-based redundancy analysis (db-RDA) using relative abundances of the predominant 29 phyla/ subphyla and also using 1000+ species was used to test for differences in overall bacterial community composition.