Hydrophysical expedition on board the R/V “G.Yu. Verschagin” on July 16-27, 2023
The field works were carried out on board the R/V “G.Yu. Verschagin” on July 16-27, 2023 within the State assignments “Investigation of the advective and turbulent water exchange of Lake Baikal and its impact on the lake ecosystem, risks of catastrophic events” (0279-2021-0004) (led by I.A. Aslamov), “From the cell to the ecosystem: Investigation of the ultrastructure of hydrobionts and their communities in the evolutionary and ecological aspect by methods of cell biology and genomics” (0279-2021-0008) (led by Ye.V. Likhoshway) and “Study of transformations in the state of water bodies and watercourses of East Siberia in seasonal and long-term aspects in terms of climate changes, geological environment and anthropogenic pressure” (0279-2021-0005) (led by A.P. Fedotov).
The expedition was aimed to assess the impact of the advective and turbulent water exchange on the Lake Baikal ecosystem that determines the quality of its waters.
Fieldworks were carried out in three lake basins and in Barguzinsky bay, Chivyrkuisky bay and in the Maloye More Strait. Sampling was carried out according to a standard grid of stations at fixed horizons from surface to bottom using a Carousel SBE-32 sampler equipped with 24 bathometers with a capacity of 5 liters. Water samples were taken for chemical analysis for methane content and to investigate the spatial distribution of dominant microalgae species throughout the Lake Baikal water area. Samples of phytoplankton were taken using a Juday net. Water was sampled at 37 stations. Hydrophysical measurements were carried out at 53 stations by high-precision CTD-probe SBE-25 with additional sensors of dissolved oxygen, transparency and suspended solid concentration.
Total number of samples:
- to determine the concentration of methane – 387
- chemical analysis – 196
- phytoplankton (net samples) – 19
- phytoplankton (with bathometers) – 99
With the course of the vessel, temperature and electrical conductivity of water surface were recorded, and the seeps of gas bubble were monitored using the soft hardware based on the Furuno sonar with the echogram data recording.
In the area of the neutrino telescope near Ivanovka settlement (106 km) and Cape Nizhneye Izgolovie, the experiment was conducted with the Argos autonomous drifting buoys. The drift trajectories were obtained with the installation of underwater sails with its area of 3m2 at a depth of 4 m and 14 m.
The data collection and storage system was modernized on the previously installed agrometeorological stations with a lake level meter near Cape Elokhin and on Maly Ushkaniy Island.
