Expedition on board the RV “G. Yu. Vereshchagin” from 16 to 17 June 2022
The expeditionary works on the RV “G.Yu. Vereshchagin” were carried out during two days in South Baikal within the grant of the Russian Science Foundation: 22-14-00084 “Metagenomic analysis of microbial communities in the gradient zones of the sedimentary strata of Lake Baikal, search for new taxa and metabolic pathways” (Leader by T. Zemskaya).
The fieldworks were done in three areas of South Baikal: i) in the deep-water zone, ii) at the Kedr mud volcano and iii) at the methane seep Goloustnoe. The bottom sediments from the first site were collected considering: aerobic and anaerobic condition, sediment layers enriched by iron-manganese, and concentrations of methane and main ions. At the Kedr mud volcano, special focus was to sampling of the sediment with different carbon isotopic content and various composition of microbial communities. The concentrations of CH4, CH3COO-, SO42-, HCO3- , NO3-, NO2-, Fe2+, Mn2+, NH4+ were measured to assess the zones of the processes of AOM, methangeneration, carbonate formation and formation of the iron-manganese layers. The рН and Eh were measured in the water-sediments interface and bottom sediments collected for molecular-biological research and obtaining of microbial cultures. Taking into account these data, the sediment samples were collected to isolate the native DNA and the shotgun sequencing. The experiments on cultivation under anaerobic conditions to obtain the accumulative cultures of methanogens, iron-manganese microorganisms and organic-heterotrophic bacteria and archaea were installed during the expedition.
