Effect of plant biodiversity on microbial community structure and their role in amino acid turnover in soil
2 Institute of Ecology, University of Jena
O 2.2 in Biodiversity and Nature Protection
15.04.2010, 13:15-13:30, H13
Effect of plant biodiversity on microbial community structure and their role in amino acid turnover in soil
Michaela Dippold1,2, Leopold Sauheitl1, Alexandra Weigelt3, Bruno Glaser1
1Department of Soil Physics, University of Bayreuth
2Department of Agroecosystem Research, University of Bayreuth
3Institute of Ecology, University of Jena
Little is known about the interaction of primary producer’s diversity with the microbial community. Therefore this study, taking place at a managed grassland biodiversity experiment, had the objective, to investigate plant biodiversity effects on the amount of microbial biomass and the composition of the microbial community. To evaluate the functions of microbial community the amino acid turnover was investigated after the addition of dual labelled amino acids to the plots with different plant biodiversity. 24 h after tracer application the uptake 13C and 15N by microbial biomass was measured by chloroform-fumigation-extraction. Deaminase activity and the 13CO2 efflux were measured to reflect metabolic activity of the microbial community and its effect on amino acid decomposition. Compound specific stable isotope analysis of the phospholipid fatty acids was used to identify changes of the microbial community and its tracer-uptake along the biodiversity gradient. Our results demonstrate a bottom-up effect of primary producer diversity on diversity and metabolic activity of the microbial community. The formers’ higher uptake rates for amino acids with increasing plant biodiversity and the higher turnover of the microbial community by an increased protozoan population lead to higher N-flows through the bioavailable N pools with increased biodiversity. This shows a positive feedback-mechanism of plant biodiversity.
Export as iCal:
