OXYGEN CONCENTRATION PROFILES IN SOFT-SEDIMENT OF LAKE BAIKAL (RUSSIA) NEAR THE SELENGA-DELTA

1. Microprofiles of oxygen concentration were made in soft sediments o f Lake Baikal, along three transects near the Selenga delta. This is t he first time the available oxygen in the sediment has been measured i n this lake. 2. The microprofiles had a similar and typical shape (a s ingle exception was possibly caused by bioturbation). A positive corre lation was found between the sediment oxygen penetration depth (SOP) a nd the bathymetric depth of the epilimnion, probably caused by a decre ase in oxygen sediment consumption with increasing depth. 3. The obser ved SOP values are generally very high, which is an indication of olig otrophy. A single low SOP value, observed in the northern transect, ap pears to be linked to organic pollution caused by the Selenga River.