Highly Distinct Microbial Communities in Elevated Strings and Submerged Flarks in the Boreal Aapa-Type Mire.

Large areas in the northern hemisphere are covered by extensive wetlands, which represent a complex mosaic of raised bogs, eutrophic fens, and aapa mires all in proximity to each other. Aapa mires differ from other types of wetlands by their concave surface, heavily watered by the central part, as well as by the presence of large-patterned string-flark complexes. In this paper, we characterized microbial diversity patterns in the surface peat layers of the neighboring string and flark structures located within the mire site in the Vologda region of European North Russia, using 16S rRNA gene sequencing. The microbial communities in raised strings were clearly distinct from those in submerged flarks. Strings were dominated by the Alpha- and Gammaproteobacteria. Other abundant groups were the Acidobacteriota, Bacteroidota, Verrucomicrobiota, Actinobacteriota, and Planctomycetota. Archaea accounted for only 0.4% of 16S rRNA gene sequences retrieved from strings. By contrast, they comprised about 22% of all sequences in submerged flarks and mostly belonged to methanogenic lineages. Methanotrophs were nearly absent. Other flark-specific microorganisms included the phyla Chloroflexi, Spirochaetota, Desulfobacterota, Beijerinckiaceae- and Rhodomicrobiaceae-affiliated Alphaproteobacteria, and uncultivated groups env.OPS_17 and vadinHA17 of the Bacteroidota. Such pattern probably reflects local anaerobic conditions in the submerged peat layers in flarks.

Biodiversity of macrophyte communities and associated aquatic organisms in lakes of the Vologda Region (north-western Russia).

BACKGROUND: This paper provides current data on the biodiversity of boreal lakes of the Vologda Region (north-western Russia), including macrophytes (vascular plants and macroscopic algae) and macrophyte inhabitants (invertebrates and microalgae). The raw data, given in two datasets (Sampling event dataset and an Occurrence dataset) and presented in the form of GBIF-mediated data, were collected from 139 lakes (macrophytes between 2005 and 2021, macrophyte inhabitants between 2014 and 2020). The dataset contains materials on the diversity of vascular plants (Tracheophyta, 3225 occurrences; Bryophyta, 155; Marchantiophyta, 16), macro- and microalgae (Ochrophyta, 546 occurrences; Chlorophyta, 193; Charophyta, 153; Cyanobacteria, 139; Cryptophyta, 86; Myzozoa, 33; Euglenozoa, 27; Rhodophyta, 8; Bigyra, 1) and aquatic invertebrates (Arthropoda, 1408 occurrences; Annelida, 487; Mollusca, 263; Platyhelminthes, 36; Cnidaria, 11). This paper summarises previously unpublished materials in a standardised form. NEW INFORMATION: The paper summarises the data collected during the long-term phytodiversity studies in a series of lakes of different types (Vologda Region, north-western Russia). Data on algae and invertebrates diversity were obtained in 60 different plant communities of aquatic, semi-aquatic and coastal plants or their combinations. A total of 6787 occurrences were included in the dataset, published in the global biodiversity database (GBIF) for the first time. According to the GBIF taxonomic backbone, the dataset comprised 837 taxa, including 711 lower-rank taxa (species, subspecies, varieties, forms). New records of 47 species rare and protected in the Vologda Region are given: 43 species of plants, three species of animals and one species of Cyanobacteria.

Macrophyte diversity in rivers and streams of the Vologda Region and several other regions of Russia.

BACKGROUND: The data paper contains the authors' materials on the diversity of macrophytes, macroscopic plants regardless of their taxonomic position, in rivers and streams of East European Russia and Western Siberia. These data, collected on 247 rivers and 32 streams in 13 administrative regions of the Russian Federation, were provided as an occurrence dataset presented in the form of GBIF-mediated data. The main portion of the data was obtained in water objects of the Vologda Region (5201 occurrences). In addition, occurrences from the Arkhangelsk Region (347 occurrences), Khanty-Mansi Autonomous Okrug (159), Yaroslavl Region (132), Novgorod Region (97), Kostroma Region (41), Republic of Karelia (31), Sverdlovsk Region (29), Komi Republic (28), Orenburg Region (26), Chelyabinsk Region (22), Voronezh Region (22) and Tyumen Region (18) were given. The studies were carried out mainly in the southern and middle taiga and, to a lesser extent, in the northern taiga and the forest-steppe. The analysed watercourses belong to five drainage basins: the Azov Sea, the Baltic Sea, the White Sea, the Caspian Sea and the Kara Sea. The dataset contains materials on the diversity of Plantae (6094 occurrences) and Chromista (59 occurrences). This paper, in a standardised form, summarises mostly unpublished materials on the biodiversity of lotic ecosystems. NEW INFORMATION: The paper summarises the data obtained in long-term studies of phytodiversity in a range of rivers and streams of East European Russia and, fragmentarily, Western Siberia. A total of 6153 occurrences were included in the dataset. According to the GBIF taxonomic backbone, the dataset comprises 292 taxa, including 280 lower-rank taxa (species, subspecies, varieties) and 12 taxa identified to the genus level. All the occurrences are published openly through the Global Biodiversity Information Facility (GBIF) for the first time. Most of the data were stored in field diaries and, thus, by adding the data in GBIF, we believe that other researchers could benefit from it.

Biodiversity of a boreal mire, including its hydrographic network (Shichengskoe mire, north-western Russia).

BACKGROUND: The paper is based on the dataset whose purpose was to deliver, in the form of GBIF-mediated data, diverse materials on the biodiversity of a large mire, Shichengskoe mire (Vologda Region, north-western Russia), including its various mire sites and intra-mire water bodies. The dataset was based on our materials collected for two decades (from 2000 to 2021) in different parts and biotopes of the Shichengskoe mire and complemented by scarce data obtained previously by other researchers. The data contain materials on the diversity of Animalia (2886 occurrences), Bacteria (22), Chromista (256), Fungi (111), Plantae (2463) and Protozoa (131). Within the study period, the most detailed and long-term biodiversity studies were carried out for higher plants and invertebrates. On the other hand, the data on the composition of lichens, protozoa, algae, basidiomycetes, some groups of invertebrates and, to a lesser extent, lichens and vertebrates are far less comprehensive and require further substantial research efforts. The list includes occurrences from both the peatland (mire sites and mire margins different in typology) and the objects of the mire hydrographic network. In a standardised form, this article summarises both already published (mainly in Russian) and unpublished materials. NEW INFORMATION: The paper summarises the results of long-term research on the biodiversity of a boreal mire, including its hydrographic network. A total of 5869 occurrences were included in the dataset published in the Global Biodiversity Information Facility (GBIF, gbif.org) for the first time. According to the GBIF taxonomic backbone, the dataset covers 1358 taxa, including 1250 lower-rank taxa (species, subspecies, varieties, forms) and 108 taxa identified to the genus level. Several species found in the Shichengskoe mire, mainly belonging to Bacteria, Chromista and Protozoa, have never been listed in GBIF for the territory of Russia before. The overwhelming majority of occurrences and identified species came from the territory of Shichengskiy Landscape Reserve. Due to our work, this Reserve is now the most studied regional reserve in the Vologda Region with respect to biodiversity. By the number of revealed species, it is close to two federal protected areas: Darwinskiy State Nature Biospheric Reserve and National Park "Russkiy Sever".

Rokubacteria in Northern Peatlands: Habitat Preferences and Diversity Patterns.

Rokubacteria is a phylogenetic clade of as-yet-uncultivated prokaryotes, which are detected in diverse terrestrial habitats and are commonly addressed as members of the rare biosphere. This clade was originally described as a candidate phylum; however, based on the results of comparative genome analysis, was later defined as the order-level lineage, Rokubacteriales, within the phylum Methylomirabilota. The physiology and lifestyles of these bacteria are poorly understood. A dataset of 16S rRNA gene reads retrieved from four boreal raised bogs and six eutrophic fens was examined for the presence of the Rokubacteriales; the latter were detected exclusively in fens. Their relative abundance varied between 0.2 and 4% of all bacteria and was positively correlated with pH, total nitrogen content, and availability of Ca and Mg. To test an earlier published hypothesis regarding the presence of methanotrophic capabilities in Rokubacteria, peat samples were incubated with 10% methane for four weeks. No response to methane availability was detected for the Rokubacteriales, while clear a increase in relative abundance was observed for the conventional Methylococcales methanotrophs. The search for methane monooxygenase encoding genes in 60 currently available Rokubacteriales metagenomes yielded negative results, although copper-containing monooxygenases were encoded by some members of this order. This study suggests that peat-inhabiting Rokubacteriales are neutrophilic non-methanotrophic bacteria that colonize nitrogen-rich wetlands.

Wide distribution of Phycisphaera-like planctomycetes from WD2101 soil group in peatlands and genome analysis of the first cultivated representative.

Phycisphaera-like WD2101 'soil group' is one of the as-yet-uncultivated phylogenetic clades within the phylum Planctomycetes. Members of this clade are commonly detected in various terrestrial habitats. This study shows that WD2101 represented one of the major planctomycete groups in 10 boreal peatlands, comprising up to 76% and 36% of all Planctomycetes-affiliated 16S rRNA gene reads in raised bogs and eutrophic fens respectively. These types of peatlands displayed clearly distinct intra-group diversity of WD2101-affiliated planctomycetes. The first isolate of this enigmatic planctomycete group, strain M1803, was obtained from a humic lake surrounded by Sphagnum peat bogs. Strain M1803 displayed 89.2% 16S rRNA gene similarity to Tepidisphaera mucosa and was represented by motile cocci that divided by binary fission and grew under micro-oxic conditions. The complete 7.19 Mb genome of strain M1803 contained an array of genes encoding Planctomycetal type bacterial microcompartment organelle likely involved in l-rhamnose metabolism, suggesting participation of M1803-like planctomycetes in polysaccharide degradation in peatlands. The corresponding cellular microcompartments were revealed in ultrathin cell sections. Strain M1803 was classified as a novel genus and species, Humisphaera borealis gen. nov., sp. nov., affiliated with the formerly recognized WD2101 'soil group'.

Closely Located but Totally Distinct: Highly Contrasting Prokaryotic Diversity Patterns in Raised Bogs and Eutrophic Fens.

Large areas in Northern Russia are covered by extensive mires, which represent a complex mosaic of ombrotrophic raised bogs, minerotrophic and eutrophic fens, all in a close proximity to each other. In this paper, we compared microbial diversity patterns in the surface peat layers of the neighbouring raised bogs and eutrophic fens that are located within two geographically remote mire sites in Vologda region using 16S rRNA gene sequencing. Regardless of location, the microbial communities in raised bogs were highly similar to each other but were clearly distinct from those in eutrophic fens. Bogs were dominated by the Acidobacteria (30%-40% of total 16S rRNA gene reads), which belong to the orders Acidobacteriales and Bryobacterales. Other bog-specific bacteria included the Phycisphaera-like group WD2101 and the families Isosphaeraceae and Gemmataceae of the Planctomycetes, orders Opitutales and Pedosphaerales of the Verrucomicrobia and a particular group of alphaproteobacteria within the Rhizobiales. In contrast, fens hosted Anaerolineae-affiliated Chloroflexi, Vicinamibacteria- and Blastocatellia-affiliated Acidobacteria, Rokubacteria, uncultivated group OM190 of the Planctomycetes and several groups of betaproteobacteria. The Patescibacteria were detected in both types of wetlands but their relative abundance was higher in fens. A number of key parameters that define the distribution of particular bacterial groups in mires were identified.

Data on chemical characteristics of waters in two boreal Sphagnum mires (North-Western Russia).

The dataset contains chemical parameters of waters in different mire water bodies (fen strip, bog stream, Sphagnum hollows, hollow-pools, intra-mire lakes, drainage way). Data were collected once a month from May till September 2012 and in May, July and September 2013 and 2014 in Shichengskoe and Alekseevskoe-1 mires (Vologda Region, Russia). Water samples were kept in a cooling bag and transported to the laboratory within a day. Prior to analyses, water samples were filtered (pore size 90 µm). Colour of water, pH, permanganate value, dry residues, and total iron, manganese, carbonate, phosphate, sulphate and nitrate ion concentrations were measured. Data were obtained by the atomic absorption spectrometry and spectrophotometric and titrimetric methods. The pH values varied from 3.7 in Sphagnum hollows to 6.9 in a bog stream and 7.2 in a primary intra-mire lake. The minimum permanganate value of 5.6 mg O/L was registered in a bog stream, the maximum of 150.4 mg O/L in a weakly waterlogged Sphagnum hollow. Dry residue values varied in a range of 35 mg/L in a large hollow-pool to 315 mg/L in a flow-through fen strip. The data are useful for investigating chemical composition of waters in different mire water bodies and the heterogeneity of these abiotic factors.

Limnoglobus roseus gen. nov., sp. nov., a novel freshwater planctomycete with a giant genome from the family Gemmataceae.

The family Gemmataceae accommodates aerobic, chemoorganotrophic planctomycetes, which inhabit various freshwater ecosystems, wetlands and soils. Here, we describe a novel member of this family, strain PX52T, which was isolated from a boreal eutrophic lake in Northern Russia. This isolate formed pink-pigmented colonies and was represented by spherical cells that occurred singly, in pairs or aggregates and multiplied by budding. Daughter cells were highly motile. PX52T was an obligate aerobic chemoorganotroph, which utilized various sugars and some heteropolysaccharides. Growth occurred at pH 5.0-7.5 (optimum pH 6.5) and at temperatures between 10 and 30 °C (optimum 20-25 °C). The major fatty acids were C18 : 1É·7c, C18 : 0 and ßOH-C16:0; the major intact polar lipid was trimethylornithine, and the quinone was MK-6. The complete genome of PX52T was 9.38 Mb in size and contained nearly 8000 potential protein-coding genes. Among those were genes encoding a wide repertoire of carbohydrate-active enzymes (CAZymes) including 33 glycoside hydrolases (GH) and 87 glycosyltransferases (GT) affiliated with 17 and 12 CAZy families, respectively. DNA G+C content was 65.6 mol%. PX52T displayed only 86.0-89.8 % 16S rRNA gene sequence similarity to taxonomically described Gemmataceae planctomycetes and differed from them by a number of phenotypic characteristics and by fatty acid composition. We, therefore, propose to classify it as representing a novel genus and species, Limnoglobus roseus gen. nov., sp. nov. The type strain is strain PX52T (=KCTC 72397T=VKM B-3275T).

100-year-old enigma solved: identification, genomic characterization and biogeography of the yet uncultured Planctomyces bekefii.

The first representative of the phylum Planctomycetes, Planctomyces bekefii, was described nearly one century ago. This morphologically conspicuous freshwater bacterium is a rare example of as-yet-uncultivated prokaryotes with validly published names and unknown identity. We report the results of molecular identification of this elusive bacterium, which was detected in a eutrophic boreal lake in Northern Russia. By using high-performance cell sorting, P. bekefii-like cell rosettes were selectively enriched from lake water. The retrieved 16S rRNA gene sequence was nearly identical to those in dozens of metagenomes assembled from freshwater lakes during cyanobacterial blooms and was phylogenetically placed within a large group of environmental sequences originating from various freshwater habitats worldwide. In contrast, 16S rRNA gene sequence similarity to all currently described members of the order Planctomycetales was only 83%-92%. The metagenome assembled for P. bekefii reached 43% genome coverage and showed the potential for degradation of peptides, pectins, and sulfated polysaccharides. Tracing the seasonal dynamics of P. bekefii by Illumina paired-end sequencing of 16S rRNA gene fragments and by fluorescence in situ hybridization revealed that these bacteria only transiently surpass the detection limit, with a characteristic population peak of up to 104 cells ml-1 following cyanobacterial blooms.

Data on air temperature, relative humidity and dew point in a boreal Sphagnum bog and an upland site (Shichengskoe mire system, North-Western Russia).

The dataset contains microclimate parameters including air temperature, relative humidity and dew point measurements from a large wetland, Shichengskoe mire system, in Vologda Region, Russia, during four vegetation periods. Data were collected in 2013-2015 and 2017 using DT-171 data loggers (Elma Instruments). Data loggers were attached to the wooden posts at 0.5 m height from the surface. Continuous recordings were performed every 30 min providing 48 measurements of air temperature, relative humidity and dew point per day. The dataset presented in the article is of particular value to understanding the heterogeneity of abiotic parameters within mire systems.

Distinct diversity patterns of Planctomycetes associated with the freshwater macrophyte Nuphar lutea (L.) Smith.

Members of the phylum Planctomycetes were originally described as freshwater bacteria. Most recent studies, however, address planctomycete diversity in other environments colonized by these microorganisms, including marine and terrestrial ecosystems. This study was initiated in order to revisit the specific patterns of planctomycete diversity in freshwater habitats using cultivation-independent approaches. The specific focus was made on planctomycetes associated with Nuphar lutea (L.) Smith, an emergent macrophyte with floating leaves, which is widespread in the Holarctic. As revealed by Illumina pair-end sequencing of 16S rRNA gene fragments, the bacterial assemblages colonizing floating leaf blades of waterlilies sampled from two different boreal lakes displayed similar composition but were distinct from the planktonic bacterial communities. 16S rRNA gene fragments from the Planctomycetes comprised 0.1-1 and 1-2.2% of total 16S rRNA gene reads retrieved from water samples and plant leaves, respectively. Planktonic planctomycetes were mostly affiliated with the class Planctomycetaceae (77-97%), while members of the Phycisphaerae were less abundant (3-22%). The relative proportion of the latter group, however, increased by 13-45% on leaves of N. lutea. The Phycisphaera-related group WD2101, Pirellula-like planctomycetes, as well as Gemmata, Zavarzinella and Planctopirus species were the most abundant groups of planctomycetes associated with plant leaves, which may suggest their involvement in the degradation of plant-derived organic matter.