Assessment of the Current Trophic Status of the Southern Baikal Littoral Zone

Eutrophication is a major ecological problem and affects endangers freshwater bodies, making assessment of the trophic status water bodies crucial for their restoration sustainable use. Lake Baikal affected by number environmental stressors, including coastal eutrophication. Daily measurements concentrations nutrients, dissolved oxygen (DO), chlorophyll-a (Chl-a), weekly algae abundance biomass in open season June-December 2020, nutrients at 2–7-day intervals June-October 2021 were made littoral South first time. It was shown that nitrate phosphate decreased July-August, minimum content maintained until September, began to increase October reached maximum December. The chlorophyll only observed early July. Storm situations increased nitrogen, phosphorus DO water, duration influence not more than 2 days. A correlation matrix revealed significant positive correlations NO3−-DO, (SPR)-NO3−, SRP-DO biomass-Chl-a strong negative between temperature (Tw)-DO, Tw-NO3−, Tw-total nitrogen (TN) Tw-SRP. Based on SRP NO3− TN:TP ratios, it concluded algal development limited summer. Southern zone assessed using classifications based TN, TP, NO3−, SRP, Chl-a biomass, as well Carlson index (TSI) probabilistic assessment. results assessments different methods determination showed study area belongs oligotrophic type with minor elements mesotrophy. According saprobity index, purity waters varies within oligosaprobic β-mesosaprobic zones corresponded quality classes II III (clean moderate purity); system demonstrates high capacity self-purification.