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

Abstract 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 This paper, in a standardised form, summarises mostly unpublished materials on the biodiversity of lotic ecosystems.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.


Introduction
Macrophytes are an essential component of lotic ecosystems, especially in terms of biodiversity (Chambers et al. 2008), playing an important functional role, providing trophic resources and habitat for other aquatic organisms (Biggs 1996, Grenouillet et al. 2002 and regulating water flows and their chemistry (e.g. Carpenter and Lodge 1986, Clarke and Wharton 2001, Horvath 2004, Gurnell et al. 2006. Under the Water Framework Directive (European Commision 2000), macrophytes are one of the key indicators used for environmental health assessment.
The study summarises the authors' materials collected in the rivers of the European part of Russia between 2005 and and Western Siberia in 2021. A small part (5.5%) of the data was published in the research articles (Ivicheva et al. 2018), but mainly as short notes on the new records (Dulin et al. 2009, Afonina et al. 2010, Abolin et al. 2011, Bobrov and Philippov 2012, Sofronova et al. 2012, Shabunov and Philippov 2014, Vishnyakov and Philippov 2018, Vishnyakov et al. 2020, Vishnyakov et al. 2021.
All the raw data on the biodiversity in rivers and streams are provided in an occurrence dataset .

Project description
Title: Diversity, distribution, ecology, biology of aquatic and semi-aquatic plants in the European North Personnel: Dmitriy A. Philippov

Sampling methods
Study extent: A list of records of macrophytes in rivers and streams of European Russia and Western Siberia is presented. By macrophytes, we understood macroscopic plants, regardless of their taxonomic position and ecological characteristics. Macrophytes include vascular plants, mosses, liverworts and large multicellular algae (Papchenkov et al. 2003). We determined the flora of rivers and streams as aquatic species and species directly related to the aquatic environment (helophytes, plants of the water's edge, amphibious plants, hygrophytes, plants of drying sandbanks).

Sampling description:
Field studies were carried out from May to October, mainly during the greatest development of macrophytes (July and August). The composition of the flora of rivers and streams was established during route field studies. We studied all available microhabitats in the channel and coastal parts of water bodies, including those differing in current velocity, sediments, depths and macrophyte canopy development. When studying streams, the route, as a rule, ranged from 50 to 150 m; on rivers, usually from 100 to 1000 m. In the Vologda Region, studies were carried out in all landscapes; several objects per type of landscape were selected depending on the density of the river network. In other regions, studies were carried out along with the study of other wetland ecosystems. In all studied regions, one route per water object was made. In the field, photographs of plants and their communities were taken, floristic lists were compiled and the main hydrochemical parameters were measured (water temperature, pH and TDS). The studies of the macrophyte community composition were conducted both purposefully and along with the studies of other groups of aquatic organisms. Macrophyte samples were collected; they are currently stored and being registered in the Herbaria of Mire Research Group, Papanin Institute for Biology of Inland Waters Russian Academy of Sciences (coded MIRE) and Vologda State University (coded VO). More than 1000 macrophyte specimens were collected in total.
Quality control: The data were collected and identified by scientists from the Papanin Institute for Biology of Inland Waters Russian Academy of Sciences (IBIW RAS). The accuracy of determination of some samples was confirmed by experts from the Institute of Biology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences and Institute of Biology of Karelian Research Centre of the Russian Academy of Sciences Step description: Research problem formulation.
Logistic issues resolution, including the choice of routes, water objects, time and duration of work.
Field stage: obtaining samples and other original materials on the flora of rivers and streams. In the field, pictures of plants and floristic lists were taken, some species were collected in a herbarium; several hydrochemical parameters (water temperature, total dissolved solids, pH and electrical conductivity) were measured using portable devices (Philippov et al. 2017).
Data collection: analysis of samples not identified in the field or verification of the identification data by the experts. The keys by Tzvelev (2000), Ignatov and Ignatova (2003), Ignatov and Ignatova (2004), Lisitsyna et al. (2009) and Maevskii (2014) were used in the study. Herbarium materials were transferred for processing to the Herbarium of the Mire Research Group of Papanin Institute for Biology of Inland Waters Russian Academy of Sciences (MIRE).
Records list compilation. The dataset field names were chosen according to Darwin Core (Wieczorek et al. 2012). Georeferencing was made by fixing the coordinates of the middle part of the studied river site using a GPS navigator or Google maps. Coordinates accuracy was set to the fourth digit. In all cases, the WGS-84 coordinate system was used.

Geographic coverage
Description: The studies were carried out in various parts of European Russian and Western Siberia, mainly in the southern and middle taiga and a lesser number 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 coordinates of the northernmost site were 64.5729N, 43.2959E, the southernmost site 51.8139 N, 39.3836 E, the westernmost site 58.4353N, 33.2828E and the easternmost site 60.8691N, 76.4263E (Fig. 1).
Some examples of the studied rivers are given below (Figs 2, 3, 4, 5, 6). Study area and occurrences localities (red circles). The map was constructed using ArcGis 10 software.     taxonRank The taxonomic rank. kingdom The full scientific name of the kingdom in which the taxon is classified. phylum The full scientific name of the phylum or division in which the taxon is classified. class The full scientific name of the class in which the taxon is classified. order The full scientific name of the order in which the taxon is classified. family The full scientific name of the family in which the taxon is classified.

genus
The full scientific name of the genus in which the taxon is classified.
habitat A category or description of the habitat in which the occurrence was recorded (river or stream). decimalLatitude The geographic latitude in decimal degrees of the geographic centre of the data sampling place.
decimalLongitude The geographic longitude in decimal degrees of the geographic centre of the data sampling place.
geodeticDatum The ellipsoid, geodetic datum or spatial reference system (SRS) upon which the geographic coordinates given in decimalLatitude and decimalLongitude are based.
coordinatePrecision A decimal representation of the precision of the coordinates given in the decimalLatitude and decimalLongitude. A constant ("0.0001").
countryCode The standard code for the Russian Federation according to ISO 3166-1-alpha-2 (RU).
county District ('rayon', in Russian administrative subdivision system) name. The secondlevel administrative division. locality The specific description of the place. This term may contain information modified from the original to correct perceived errors or standardise the description. A variable (names of rivers or springs). year The four-digit year in which the Event occurred, according to the Common Era Calendar.

month
The integer month in which the Event occurred. day The integer day of the month on which the Event occurred.
recordedBy List of persons who collected field data.
identifiedBy A person who assigned the Taxon to the subject. dateIdentified The date when the taxonomic identification happened.
associatedReferences List of literature references associated with the occurrences (articles). acceptedNameUsage The full name, with authorship and date information, if known, of accepted taxon. taxonomicStatus The taxonomic status of a taxon. A variable (accepted or synonym).

Additional information
The data were collected on 247 rivers and 32 streams of East European Russia and Western Siberia and included 6153 occurrences of macrophytes (280 lower-rank taxa and 12 taxa identified to the genus level).
These studies have been conducted since 2005. From 8 to 1404 occurrences were registered each year (Fig. 7). The most productive years in respect to macrophyte studies in rivers and streams were 2011, 2013, 2017, 2018, 2020 and 2021. In any given year, the greatest emphasis was on rivers, not streams.
The studies were conducted in 13 administrative regions of Russia (Table 1). The greatest number of water objects were investigated in the Vologda Region (190 rivers and 26 streams). In the Arkhangelsk Region, 30 rivers and streams were studied; in other 11 administrative regions, from 1 to 7 rivers and streams. Therefore, the most occurrences and lower-rank taxa records came from the Vologda Region (5201 and 266, respectively). Distribution of macrophyte occurrences in rivers and streams from 2005 to 2021. Number of occurrences and taxa of macrophytes in rivers and streams in the studied regions. Table 2.

Number of occurrences
Top 50 rivers by the number of macrophyte occurrences amongst the 279 studied rivers and streams of Russia.

River
The studies have provided data on the locations of a number of rare macrophyte species.