The effect of drainage ditches networks on soil archaeal and bacterial community structure and abundance, as well as on nitrogen cycling processes was studied in full-drained peatland forests

The effect of drainage ditches networks on soil archaeal and bacterial community structure and abundance, as well as on nitrogen cycling processes was studied across the distance gradient from a drainage ditch in full-drained peatland forests (Scots pine forests of Vaccinium-type, and Oxalis-type Norway spruce and Downy birch forests) of Estonia. The study stands (three stands per each forest type) were growing on Histosol. In total 36 composite soil samples were taken from 0-10 cm layer in November 2014. In addition to the 16S rRNA gene fragment sequencing (Illumina MiSeq), bacterial and archaeal 16S rRNA genes, as well as nitrogen-cycling genes copy numbers were determined using qPCR. Additionally, soil chemical characteristics were determined and N2O emissions were measured in situ at the sampling while N2O and N2 emissions from the collected soil samples were measured also in the laboratory. Some plant root characteristics (tree root biomass and its proportion in the total plant root biomass, tree root turnover rate) were also measured in all sampling points.