impact of grassland management regime on the community structure of selected bacterial groups in soils

• Published in: FEMS microbiology ecology Vol. 43; no. 2; pp. 263 - 270
• Main Authors: Clegg, C.D, Lovell, R.D.L, Hobbs, P.J
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.03.2003; Blackwell; Oxford University Press
• Subjects: 16S rDNA; Actinomycetales; Actinomycetes; Agronomy. Soil science and plant productions; Ammonia; Animal, plant and microbial ecology; Binary data; Biochemistry and biology; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; Clustering; Coefficients; Community composition; Community structure; Correlation analysis; denaturing gradient gel electrophoresis; DGGE profiling; Drainage; Ecology; Electrophoresis; Fatty acids; Fertilizer application; Fundamental and applied biological sciences. Psychology; Gel electrophoresis; Grassland; Grassland management; Grasslands; long term effects; Management; microbial communities; Microbial ecology; Microbiology; Microorganisms; Multivariate analysis; Nitrogen; nitrogen fertilizers; Organic matter; Organic soils; Phospholipid fatty acid; phospholipid fatty acids; Phospholipids; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Polymerase chain reaction; principal component analysis; Principal components analysis; range management; Similarity; Soil; Soil analysis; Soil management; Soil microorganisms; Soil organic matter; Soil science; Soil structure; soil treatment; Soils; Grassland; 16S rDNA; Phospholipid fatty acid; Multivariate analysis; DGGE profiling; Community structure; Gradient; Gel electrophoresis; Eubacteria; Phospholipid; Organic soil; Soil structure; Long term; Polymerase chain reaction; Grassland management; Bacteria; Actinomycetes; Microbial community
• ISSN: 0168-6496; 1574-6941
• DOI: 10.1111/j.1574-6941.2003.tb01066.x

The impact of long-term grassland management regimes on microbial community structure in soils was assessed using multivariate analysis of polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) banding patterns of selected bacterial groups and PLFA (phospholipid fatty acid) profiling. The management regimes assessed were inorganic nitrogen (N) fertiliser application and soil drainage. PCR-DGGE profiles of the eubacteria, actinomycetes, ammonia oxidisers and pseudomonads were assessed by principal co-ordinate analysis of similarity indices which were generated from binary data using both Dice and Jaccard coefficients. The analysis of binary DGGE data revealed significant impacts of N fertiliser on the eubacterial and actinomycete community structure using the Jaccard coefficient, whilst N fertiliser had a significant impact on the actinomycete community structure only when using similarity indices generated from the Dice coefficient. Soil drainage had a significant impact on the community structures of the actinomycetes and the pseudomonads using both Dice and Jaccard derived similarity indices. Multivariate analysis of principal components derived from PLFA profiling revealed that N fertiliser had a significant impact on the microbial community structure. Although drainage alone was not a significant factor in discriminating between PLFA community profiles of the different treatments, there was a significant interaction with N fertiliser. Analysis of principal component analysis (PCA) loadings revealed that PLFAs i15:0 and i17:0 were partly responsible for the clustering away of the undrained-N fertilised treatment. Although soil management regime influenced some background soil data, correlation analysis using PC1 from PLFA data revealed no significant relationship with soil organic matter, pH, total C and total N. These results provide evidence that grassland management practices impact on the community composition of specific microbial groups in soils.