# Impact of High Water Levels in Lake Baikal on Rare Plant Species in the Coastal Zone
## 3 Results and Discussion
In the course of fieldwork, rare plant species were recorded at eight sites: the vicinity of Babushkin town; the sandy spit of Posolsky sor bay; the Lemasovo area; in the vicinity of the villages of Gremyachinsk, Goryachinsk, Turka, and Ust-Barguzin; and the coast of Barguzin Bay (Chivyrkuisky Isthmus) (Figure 4). A total of three populations of _D. turczaninowii_, two populations of _C. ulopterum_, one population of _A. sericecanus_, and seven populations of _C. subvillosum_ were identified. The number of plants of each population was counted, and the number of individuals subjected to inundation at different lake water levels was identified within vector polygons (Table 1). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Lake Baikal** & _Craniospermum_ & _Deschampsia_ & _Corisperum_ & _Astragalus_ & **Total,** \\
**Water Level** & _subvillosum_ & _turczaninowii_ & _ulopterum_ & _sericecanus_ & **Pcs.** \\ \hline
457.00–457.10 & 0 & 373 & 0 & 0 & 373 \\
57.10–457.20 & 83 & 373 & 0 & 0 & 456 \\
457.20–457.30 & 107 & 373 & 0 & 0 & 480 \\
457.30–457.40 & 137 & 373 & 0 & 0 & 510 \\
457.40–457.50 & 213 & 373 & 0 & 0 & 586 \\
457.50–457.60 & 482 & 373 & 0 & 0 & 855 \\
457.60–457.70 & 803 & 373 & 21 & 0 & 1197 \\
457.70–457.85 & 4737 & 373 & 30 & 24 & 5164 \\ Total. pcs. & 4737 & 373 & 30 & 24 & 5164 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Abundance of rare plant species subject to inundation at different water levels of Lake Baikal. Figure 4: Key areas with rare plant species along the southeastern shore of Lake Baikal. Circles denote the presence of species in the location. Yellow—_D. turczaninowii_ (2 locations); pink—_A. sericocanus_ (1 location); green—_C. ulopterum_ (2 locations); blue—_C. subvillosum_ (7 locations). _D. turczaninowii_ is the most vulnerable species to the risk of inundation due to its growth directly adjacent to bodies of water. All of its habitats are subject to inundation, with elevations ranging up to 457.10. Despite the fact that the _D. turczaninowii_ has high resistance and is capable of renewal and vegetative reproduction through the rooting of storm-torn parts of turf and rosettes, any change in the level of Lake Baikal may lead to changes in habitat conditions and its potential extinction [43,44]. A total of 373 individuals were affected by the inundation at the three survey sites. In the vicinity of the Goryachinsky village, two relatively large populations were recorded on a stony substrate with a predominance of the generative stage and a density of 6-7 species per 1 m\({}^{2}\). During the 2022 fieldwork, the _D. turczaninowii_ population in the vicinity of Babushkin was already partially inundated. _A. sericeoanus_ has been observed to inhabit the high terraces. However, within the proximity of Turka village, a population of 24 individuals was documented to fall within the flood zone, specifically at elevations exceeding 457.70 m. The estimated density within this area was recorded to be 0.06 per square meter. The high water level of Lake Baikal does not pose a direct threat to the main part of the population located at this site on sand dunes. The second habitat of the species in the northern part of Lake Baikal (Yarki Island), which is listed in the Red Book, was not surveyed during the 2022 field season. The island is subject to flooding, which is likely to exacerbate the total losses and damage costs. The number of _C. subvillosum_ specimens in the flood zone reaches 4737. In the vicinity of the villages of Goryachinsky, Gremyachinsky, and on the Chivyrkuisky Isthmus, the _C. subvillosum_ grows in a continuous line, in contrast to the areas around Babushkin, Posolsk, and Lemasovo, where the distribution area is disjunctive. The surveyed populations are at different ontogenetic stages, with the majority being in the virginile stage. The predominance of seedlings and juvenile species was observed on the beaches near Turka, while in the populations of Gremyachinsky and at the northern end of the Chivyrkuisk Isthmus, there is a predominance of generative species.