Soil metagenome after added nitrogen
Soils were destructively harvested with each soil mixed by hand with a sterile implement in the original incubation tube prior to freezing at -20C before transporting, frozen, to the South Australian Genomics Centre (SAGC), Australia, for DNA extraction and sequencing. Samples were forwarded to the AGRF Ltd., Australia where DNA extractions were conducted on 250 mg of soil with up to 10% variation using the Qiagen DNeasy PowerSoil Pro Kit as per the manufacterers protocol. DNA quantity was checked via Qubit Fluorometric Quantification (Thermo Fisher Scientific, Waltham MA, USA) with size distribution quantified using TapeStation electrophoresis (Agilent, Santa Clara CA, USA). DNA was sequenced at SAGC using MGI DNBSEQ G400 with libraries generated according to the Illumina DNA Prep protocol (10000000254 16 v10) with 12 amplification cycles. All libraries were a similar size and quantity and totalled 1.68 billion reads passing the quality filter.