Home – Home – Jornals – Flora and Vegetation of Asian Russia 2022 number 4

In 1968-1985, in the course of study of phytobenthos in the Lake Baikal, L.A. Izhboldina sampled and analyzed material on the structure and distribution of meio- and microphytobenthos in Chivyrkuyskiy Gulf, the second-largest gulf in the lake. Until now, just a general description of phytobenthos structure was published. The article presents schemes of 18 profiles, 12 of which (more than three quarters of sampled data) were laid during July 1985. For each profile we have drawn a scheme where indicated dominant and codominant species, type of bottom substrate, generalized biomass of community (gr/m²) and the number of species for every station (sampling site). Due to the predominance of shallow depths and mechanically unstable sandy, silty-sandy and silty substrates, the structure of benthic vegetation is monotonous, and phytobenthos belts described for Lake Baikal, are not expressed. There is also a certain gradient in communities along the central part of the gulf from its top to the mouth. Small bays along the western shore of the gulf have certain specificity. In some parts of the gulf, Chaetomorpha curta (Chlorophyta), Cladophora aegagriopila, C. meyeri, C. meyeri var. gracilior (Chlorophyta), Collema ramenskii (Ascomycota), Gloeothrichia pisum (Cyanophyta), Nostoc pruniforme (Cyanophyta) are comparatively frequent and abundant. Noteworthy, the high occurrence of such algae as G. pisum and C. aegagropila, which are absent in littoral of the open Baikal. Charophyta (Chara sp., Nitella sp.) often form communities at depths of 5-8 m. Among vascular plants, the most active are Lemna trisulca and Potamogeton perfoliatus. The alien North American Elodea canadensis and the zignem algae Spirogyra sp., settled in the lake and experienced catastrophic outbreaks of development in subsequent years, in 1985 were represented by few samples.