The "Flora of Russia" project on iNaturalist brought together professional scientists and amateur naturalists from all over the country. Over 10,000 people were involved in the data collection. Within 20 months, the participants accumulated 750,143 photo observations of 6,857 species of the Russian flora. This constitutes the largest dataset of open spatial data on the country’s biodiversity and a leading source of data on the current state of the national flora. About 87% of all project data, i.e. 652,285 observations, are available under free licences (CC0, CC-BY, CC-BY-NC) and can be freely used in scientific, educational and environmental activities.

Sparganiumis an emergent aquatic macrophyte widely spread in temperate and subtropical zones. Taxa of this genus feature high phenotypic plasticity and can produce interspecific hybrids. By means of high-throughput sequencing of the internal transcribed spacer (ITS1) of 35S rDNA, the status of 15 EurasianSparganiumspecies and subspecies was clarified and the role of hybridization events in the recent evolution of the genus was investigated. It has been shown that a number of species such asS. angustifolium, S. fallaxandS. subglobosumhave homogenized rDNA represented by one major ribotype. The rDNA of other taxa is represented by two or more major ribotypes. Species with high rDNA heterogeneity are apparently of hybrid origin. Based on the differences in rDNA patterns, intraspecific diversity was identified inS. probatovaeandS. emersum. Thus, we have concluded thatSparganiumhas extensive interspecific hybridization at the subgenus level, and there may also be occasional hybridization between species from different subgenera.

The study represents the results of research of intragenic polymorphism in transcribed spacer ITS1 of the 35S rRNA genes in representatives of subgenus Xanthosparganium genus Sparganium which were obtained by means of locus-specific next generation sequencing on the platform Illumina MiSeq. It was shown that ribotype variations in studied samples generally correspond to the division of this genus into three sections Erecta (subgenus Sparganium), Natantia and Minima (subgenus Xanthosparganium). High level of intragenic polymorphism was revealed in S. hyperboreum, with ribotypes distributed among several groups. Genome of this species includes ribotypes which are typical for other species in subgenus Xanthosparganium. For two investigated S. glomeratum samples, there were no ribotypes similar to such ribotypes in other species of Natantia section. S. glomeratum has got ribotypes identical with S. hyperboreum of Minima section. This feature may be the evidence of ancient intersectional hybridization of these two species. Characteristics of rDNA in S. glomeratum are in favor of putting this species into Minima section. It was suggested that speciation processes within the genus could be based not only on hybridization but also went on in allopatric way. The fist statement is supported by the presence of similar and identical ribotypes in S. emersum, S. longifolium, S. gramineum and S. hyperboreum, the second as it was mentioned by other researchers, is due to close relationship between North American and Eurasian taxa.

The phytoplankton and vascular aquatic plants have been studied in small lakes Vashutinskoe, Chashnitskoe, Ryumniki, and Zaozer’e, located in the southern part of the Yaroslavl Region, Russia. The taxonomic composition of phytoplankton comprised 137 species of algae belonging to 8 divisions, 18 orders, and 76 genera. The studied water bodies were characterized by high biomass of cyanobacteria. Aphanizomenon flos-aquae (L.) Ralfs ex Born et Flah. and the species of the genus Anabaena had a significant contribution to the phytoplankton biomass in the lakes Zaozer’e, Chashnitskoe, and Ryumniki, Limnothrix planctonica (Wołosz.) Meff. and Microcystis aeruginosa (Kütz.) Kütz, in the Lake Vashutinskoe. In terms of phytoplankton biomass, the pelagial and shallow areas of the Lake Vashutinskoe belonged to eutrophic reservoirs, of the Lake Ryumniki, to oligotrophic. The phytoplankton biomass in the pelagial zone of the lakes Chashnitskoe and Zaozer’e indicated the mesotrophic status of these water bodies, in the littoral zone, eutrophic. The study of the phytoplankton of the lakes was carried episodically and was often performed at different periods of the growing season. Therefore, the obtained data did not allow one to assess the direction of the successional changes in the algal flora. The flora of vascular plants of lakes was represented by 118 species belonging to 4 divisions, 5 classes, 22 orders, and 37 families. Thirty-four species were common to all studied water bodies. The differences in the The differences in the flora of vascular aquatic plantsof the studied lakes were associated with differences in their trophic status, the presence of various biotopes, the nature of anthropogenic load, and the degree of eutrophication. During a hundred years of observations, some species have disappeared, but some have appeared, including adventive species (such as Elodea canadensis Michx., Bidens frondosa L., Epilobium adenocaulon Hausskn, Zizania latifolia Griseb., and Juncus tenuis Willd.). The study of the current state of rare and protected species of vascular plants made it possible to reveal the eventual causes and period of disappearance of some species from the lakes. The taxonomic and ecological structure of phytoplankton and vascular plants of lakes was quite diverse and usual for the water bodies of the European part of Russia.

The morphology of the vegetative and generative sphere of the relic species Sparganium gramineumGeorgi, collected from lakes of the central region of European Russia (Moscow, Tver, and...

Nuphar lutea (L.) Sm. (Nymphaeaceae Salisb.) belongs to the category of highly active cenose-forming plants in water bodies and water flows. The material for study of morphological peculiarities and seed productivity of the fruits of this species was collected mainly in the lake ecosystems of the Central Part of European Russia and Republic of Belarus. In the study we used biomorphological and ontogenetic approaches. Seed productivity was surveyed by direct count of number of seeds in the fruit. By abundance (in descending order), the significant reliable inter-lake differences in a number of morphological parameters of the fruit fall into the following sequence: number of rays of stigma of fruit (in six pairs of lakes) > length of fruit (in four pairs of lakes) > diameter of the stigma of fruit (in three pairs of lakes) > diameter of fruit (in two pairs of lakes) > length of the neck of the fruit (in one pair of lakes). Intra-regional differences in certain morphological parameters of fruits (by number of rays of stigmas) were most notably manifested only in the Belarus lakes which are similar by trophic status. All the differences in the fruits’ morphology could be due to differences in the habitat by the amount of nutrients in water and soil. The amount of seed productivity of the fruits from N. lutea varies broadly. Analysis of this parameter depending on the character of soils in which the plants grew indicated reliable results only in the case of muddy (296 ± 81) and sandy soils (179 ± 13). We determined that distribution of generative diasporas of N. lutea across large distances is related not only to presence of floating ability in the seeds, but also the “multi-step” process of their release: first – mericarps from fruits, and then seeds from mericarps. In the experimental conditions, most seeds directly sunk to the bed (70%) and the rest continued to float on the surface of the water during a month. Low germination of the seeds of the water-lily in the laboratory conditions (4–6%) with use of different means and terms of dry stratification was due to the fact that they have an organic morphophysiological intermediate type of rest. Having such a mechanism causes portioned and prolonged germination, allowing the species to survive in non-favourable conditions and accumulate generative diaspores in the soil. Despite the fact that the initial stages of ontogenesis in the laboratory and natural conditions have no significant differences, we found polyvariance in their tempo of development. First of all, this is related to different dates of transition of the plant from one age state to another. In the case of N. lutea, one should also note the morphological polyvariance of ontogenesis related to change in morphologic characteristics of plants depending on the water level. The obtained results give a more complete picture of the peculiarities of generative reproduction of N. lutea, necessary for understanding the ecosystem role of this plant and its impact on biological processes in water bodies.