title: Microbial communities show parallels at sites with distinct litter and soil characteristics.
abstract: Plant and microbial community composition in connection with soil chemistry determines soil nutrient cycling. The study aimed at demonstrating links between plant and microbial communities and soil chemistry occurring among and within four sites: two pine forests with contrasting soil pH and two grasslands of dissimilar soil chemistry and vegetation. Soil was characterized by C and N content, particle size, and profiles of low-molecular-weight compounds determined by high-performance liquid chromatography (HPLC) of soil extracts. Bacterial and actinobacterial community composition was assessed by terminal restriction fragment length polymorphism (T-RFLP) and cloning followed by sequencing. Abundances of bacteria, fungi, and actinobacteria were determined by quantitative PCR. In addition, a pool of secondary metabolites was estimated by erm resistance genes coding for rRNA methyltransferases. The sites were characterized by a stable proportion of C/N within each site, while on a larger scale, the grasslands had a significantly lower C/N ratio than the forests. A Spearman's test showed that soil pH was correlated with bacterial community composition not only among sites but also within each site. Bacterial, actinobacterial, and fungal abundances were related to carbon sources while T-RFLP-assessed microbial community composition was correlated with the chemical environment represented by HPLC profiles. Actinobacteria community composition was the only studied microbial characteristic correlated to all measured factors. It was concluded that the microbial communities of our sites were influenced primarily not only by soil abiotic characteristics but also by dominant litter quality, particularly, by percentage of recalcitrant compounds.
authors.affiliation: Laboratory for Diagnostics and Epidemiology of Microorganisms, Crop Research Institute, Drnovska 507, 16106 Prague 6, Czech Republic.
authors.forename: Marketa
authors.initials: M
authors.lastname: Sagova-Mareckova
authors.forename: Marek
authors.initials: M
authors.lastname: Omelka
authors.forename: Ladislav
authors.initials: L
authors.lastname: Cermak
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Kamenik
authors.forename: Jana
authors.initials: J
authors.lastname: Olsovska
authors.forename: Evelyn
authors.initials: E
authors.lastname: Hackl
authors.forename: Jan
authors.initials: J
authors.lastname: Kopecky
authors.forename: Franz
authors.initials: F
authors.lastname: Hadacek
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D058491:Bacterial Load; D044822:Biodiversity; D002244:Carbon / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D016000:Cluster Analysis; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005658:Fungi / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D008780:Methyltransferases / Q000235:genetics; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000032:analysis; D009930:Organic Chemicals / Q000032:analysis; D010802:Phylogeny; D010944:Plants / Q000382:microbiology*; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology
chemical_list: D004269:DNA, Bacterial; D009930:Organic Chemicals; D012987:Soil; D002244:Carbon; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase; D009584:Nitrogen