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Khanaev, I.

Publications and source records attributed to Khanaev, I..

2 recordsLinked to original sources

Changes in the microbial community of Lubomirskia baicalensis affected by Brown Rot Disease

Sponge diseases occur globally and the resulting reduction of sponge populations has negative effects on other organisms within the ecosystems due to loss of nutrient enrichment and loss of bioremediation. In Lake Baikal, the predominate sponge species Lubomirskia baicalensis is currently being infected with an unidentified pathogen resulting in a sharp decline in population. The current hypothesis is that the recent increase in methane concentration in the lake has caused dysbiosis within the bacterial community of L. baicalensis resulting in the disease outbreak. In this study we investigated the changes in the bacterial community between healthy and sick sponges using 16S bacterial profiling targeting veritable regions 3-5. Here we present data that the bacterial communities of the healthy sponge samples were significantly different from sick samples and several poorly classified organisms were identified by Indicator Species Analysis as significant. Organisms identified from the sick samples classified within taxonomic units that contain acidophilic bacteria which suggest pH may play a role. There was also an observed decrease in the number of identified methyltropic bacteria present in the sick sponge samples compared to the healthy.

ecology↗

Water motion as a transformation mechanism of algal communities structure in Lake Baikal

The diversity of algal communities of phytoplankton and meio-and macrophytes was investigated in Lake Baikal. Fragments of Spirogyra thallomes were recorded in the phytoplankton community of Southern Baikal, which had never been recorded before in its composition. It was also established that the structure of benthic algal communities changed in comparison with that in 2000 due to intense development of filamentous algae, particularly Spirogyra. Its lowest biomass was recorded in the surf zone and wave breaking, whereas the highest biomass was registered in the area of weakened effect of waves on the bottom. The cover percent of the bottom with filamentous algae in different areas of the coastal zone varied from 0 to 100%. Hydraulic characteristics of Spirogyra were the same as those of planktonic diatoms. The circulation currents and wave effect on the bottom favoured transfer and distribution of Spirogyra from the location of its intense development into the coastal area of Lake Baikal.

ecology↗