Geochemical and microbiological characteristics of sediments near the Malenky mud volcano (Lake Baikal, Russia), with evidence of Archaea intermediate between the marine anaerobic methanotrophs ANME-2 and ANME-3   总被引：1，自引：1，他引：0  

Tamara I. Zemskaya  Tatiayna V. Pogodaeva  Olga V. Shubenkova  Svetlana M. Сhernitsina  Olga P. Dagurova  Savelii P. Buryukhaev  Bair B. Namsaraev  Oleg M. Khlystov  Aleksandr V. Egorov  Aleksei A. Krylov  Gennadii V. Kalmychkov 《Geo-Marine Letters》2010,30(3-4):411-425

Detailed lithological, biogeochemical and molecular biological analyses of core sediments collected in 2002–2006 from the vicinity of the Malenky mud volcano, Lake Baikal, reveal considerable spatial variations in pore water chemical composition, with total concentrations of dissolved salts varying from 0.1 to 1.8‰. Values of methane δ¹³С in the sediments suggest a biogenic origin (δ¹³С_min. ?61.3‰, δ¹³С_max. ?72.9‰). Rates of sulphate reduction varied from 0.001 to 0.7 nmol cm^?3 day^?1, of autotrophic methanogenesis from 0.01 to 2.98 nmol CH₄ cm^?3 day^?1, and of anaerobic oxidation of methane from 0 to 12.3 nmol cm^?3 day^?1. These results indicate that methanogenic processes dominate in gas hydrate-bearing sediments of Lake Baikal. Based on clone libraries of 16S rRNA genes amplified with Bacteria- and Archaea-specific primers, investigation of microbial diversity in gas hydrate-bearing sediments revealed bacterial 16S rRNA clones classified as Deltaproteobacteria, Gammaproteobacteria, Chloroflexi and OP11. Archaeal clone sequences are related to the Crenarchaeota and Euryarchaeota. Baikal sequences of Archaea form a distinct cluster occupying an intermediate position between the marine groups ANME-2 and ANME-3 of anaerobic methanotrophs.  相似文献   

Bottom bituminous constructions and biota inhabiting them according to investigation of Lake Baikal with the Mir submersible     

O. M. Khlystov  T. I. Zemskaya  T. Ya. Sitnikova  I. V. Mekhanikova  I. A. Kaigorodova  A. G. Gorshkov  O. A. Timoshkin  O. V. Shubenkova  S. M. Chernitsyna  A. V. Lomakina  A. V. Likhoshvai  A. M. Sagalevich  V. I. Moskvin  V. I. Peresypkin  N. A. Belyaev  M. V. Slipenchuk  A. K. Tulokhonov  M. A. Grachev 《Doklady Earth Sciences》2009,429(1):1333-1336

  相似文献   

Structure and Production Potential of Summer Phytoplankton of Lake Baikal in the Present Period     

Bondarenko  N. A.  Rusanov  I. I.  Chernitsyna  S. M.  Shubenkova  O. V.  Zaharenko  A. S.  Pogodaeva  T. V.  Pimenov  N. V.  Zemskaya  T. I. 《Water Resources》2022,49(1):98-108

Water Resources - A study of the structure and production parameters of phytoplankton (biomass, photosynthesis rate, chlorophyll a content, and assimilation numbers) in the coastal and pelagic...  相似文献   

Faunal communities at sites of gas- and oil-bearing fluids in Lake Baikal     

Tamara I. Zemskaya  Tatiana Y. Sitnikova  Sergei I. Kiyashko  Gennady V. Kalmychkov  Tatiana V. Pogodaeva  Irina V. Mekhanikova  Tatiana V. Naumova  Olga V. Shubenkova  Svetlana M. Chernitsina  Oleg V. Kotsar  Evgeny S. Chernyaev  Oleg M. Khlystov 《Geo-Marine Letters》2012,32(5-6):437-451

Macro- and meiofaunal communities were examined at four geomorphologically distinct sites with different gas- and oil-bearing fluid characteristics in the northern, central and southern basins of Lake Baikal. All sites had elevated concentrations of bicarbonate, nitrate, sulphate and chloride ions in pore fluids, with highest values at the Frolikha vent. Elevated levels of iron ions were found in pore waters of the St. Petersburg methane seep and the Gorevoy Utes oil seep. The chemical composition of pore waters at the Malenky mud volcano was similar to that reported in earlier work. Consistent with published data, the Frolikha vent (northern basin) and the St. Petersburg methane seep (central basin) were characterised by methane of mixed genesis (thermogenic + biogenic), whereas the methane source was mainly thermogenic at the Gorevoy Utes oil seep (central basin) and biogenic at the Malenky mud volcano (southern basin). In contrast to marine seep ecosystems, the macrofauna was dominated only by amphipods, giant planarians and oligochaetes, whereas bivalves were absent; the meiofauna was similar to its marine counterpart, being dominated by nematodes, cyclops, harpacticoids and ostracods. A statistically significant positive relationship was revealed between faunal abundance and the availability of bacterial mats on seep sediments. Moreover, ANOVA tests showed significant increases in both meiozoobenthic and macrozoobenthic densities at “hot spot” vent/seep sites relative to discharge-free reference sites. The isotopic composition of carbon and nitrogen at various trophic levels of these benthic vent/seep communities was found to differ markedly from that reported by earlier studies for the pelagic and other benthic food webs in Lake Baikal. As in marine seeps, the macrofauna had variable isotopic signatures. Light δ¹³C and δ¹⁵N values suggest the utilization of chemosynthetically fixed and/or methane-derived organic matter. By contrast, the heavy δ¹³C signatures of some mobile amphipods likely reflect consumption of photosynthetically derived carbon. These findings would at least partly explain why Lake Baikal is a notable outlier in global temperature–biodiversity patterns, exhibiting the highest biodiversity of any lake worldwide but at an extremely cold average temperature.  相似文献