Intralandscape differentiation of the local flora in the central part of the Gydansky Peninsula (West Siberian Arctic)

The paper aims to describe Russian approaches to inventory of vascular plants diversity in the Russian Arctic. In the study, the local flora method is used. It provides comparable data for spatial comparisons between different locations. The method includes the study of species distributions within a landscape, therefore the concept of “partial flora” was elaborated. A complex estimate “activeness” allows to assess a species role within the landscape. These theoretical concepts are applied at the local flora of a hardly accessible central part of the Gydansky Peninsula. The local flora numbers 191 vascular plant species. Altogether, 18 habitat types were distinguished with partial floras numbering from 15 to 75 species. The highest alfa-diversity was recorded on steep slopes, many rare species occurred there as well. These habitats occupied less than 10% of the area but provided almost 75% of local flora. Although the morphology of relief was better developed at this locality compare to the others at the Gydansky Peninsula, the intralandscape structure of flora is continuous, showing a low beta-diversity and high similarity of species composition between different habitats. It is explained by a high proportion of “active” species, which occur in many different habitat types. Along the zonal gradient within the Gydansky Peninsula, a decrease of species richness at local flora level was found but no change at partial floras level

The High–Low Arctic boundary: How is it determined and where is it located?

Geobotanical subdivision of landcover is a baseline for many studies. The High–Low Arctic boundary is considered to be of fundamental natural importance. The wide application of different delimitation schemes in various ecological studies and climatic scenarios raises the following questions: (i) What are the common criteria to define the High and Low Arctic? (ii) Could human impact significantly change the distribution of the delimitation criteria? (iii) Is the widely accepted temperature criterion still relevant given ongoing climate change? and (iv) Could we locate the High–Low Arctic boundary by mapping these criteria derived from modern open remote sensing and climatic data? Researchers rely on common criteria for geobotanical delimitation of the Arctic. Unified circumpolar criteria are based on the structure of vegetation cover and climate, while regional specifics are reflected in the floral composition. However, the published delimitation schemes vary greatly. The disagreement in the location of geobotanical boundaries across the studies manifests in poorly comparable results. While maintaining the common principles of geobotanical subdivision, we derived the boundary between the High and Low Arctic using the most up‐to‐date field data and modern techniques: species distribution modeling, radar, thermal and optical satellite imagery processing, and climatic data analysis. The position of the High–Low Arctic boundary in Western Siberia was clarified and mapped. The new boundary is located 50–100 km further north compared to all the previously presented ones. Long‐term anthropogenic press contributes to a change in the vegetation structure but does not noticeably affect key species ranges. A previously specified climatic criterion for the High–Low Arctic boundary accepted in scientific literature has not coincided with the boundary in Western Siberia for over 70 years. The High–Low Arctic boundary is distinctly reflected in biodiversity distribution. The presented approach is appropriate for accurate mapping of the High–Low Arctic boundary in the circumpolar extent

Russian Arctic Vegetation Archive—A new database of plant community composition and environmental conditions

Motivation: The goal of the Russian Arctic Vegetation Archive (AVA-RU) is to unite and harmonize data of plot-based plant species and their abundance, vegetation structure and environmental variables from the Russian Arctic. This database can be used to assess the status of the Russian Arctic vegetation and as a baseline to document biodiversity changes in the future. The archive can be used for scientific studies as well as to inform nature protection and restoration efforts. Main types of variables contained: The archive contains 2873 open-access geobotanical plots. The data include the full species. Most plots include information on the horizontal (cover per species and morphological group) and vertical (average height per morphological group) structure of vegetation, site and soil descriptions and data quality estimations. In addition to the open-access data, the AVA-RU website contains 1912 restricted-access plots. Spatial location and grain: The plots of 1–100 m2 size were sampled in Arctic Russia and Scandinavia. Plots in Russia covered areas from the West to the East, including the European Russian Arctic (Kola Peninsula, Nenets Autonomous district), Western Siberia (Northern Urals, Yamal, Taza and Gydan peninsulas), Central Siberia (Taymyr peninsula, Bolshevik island), Eastern Siberia (Indigirka basin) and the Far East (Wrangel island). About 72% of the samples are georeferenced. Time period and grain: The data were collected once at each location between 1927 and 2022. Major taxa and level of measurement: Plots include observations of >1770 vascular plant and cryptogam species and subspecies. Software format: CSV files (1 file with species list and abundance, 1 file with environmental variables and vegetation structure) are stored at the AVA-RU website (https://avarus.space/), and are continuously updated with new datasets. The open-access data are available on Dryad and all the datasets have a backup on the server of the University of Zurich. The data processing R script is available on Dryad

Spatial patterns of arctic tundra vegetation properties on different soils along the Eurasia Arctic Transect, and insights for a changing Arctic

Vegetation properties of arctic tundra vary dramatically across its full latitudinal extent, yet few studies have quantified tundra ecosystem properties across latitudinal gradients with field-based observations that can be related to remotely sensed proxies. Here we present data from field sampling of six locations along the Eurasia Arctic Transect in northwestern Siberia. We collected data on the aboveground vegetation biomass, the normalized difference vegetation index (NDVI), and the leaf area index (LAI) for both sandy and loamy soil types, and analyzed their spatial patterns. Aboveground biomass, NDVI, and LAI all increased with increasing summer warmth index (SWI—sum of monthly mean temperatures > 0 °C), although functions differed, as did sandy vs. loamy sites. Shrub biomass increased non-linearly with SWI, although shrub type biomass diverged with soil texture in the southernmost locations, with greater evergreen shrub biomass on sandy sites, and greater deciduous shrub biomass on loamy sites. Moss biomass peaked in the center of the gradient, whereas lichen biomass generally increased with SWI. Total aboveground biomass varied by two orders of magnitude, and shrubs increased from 0 g m−2 at the northernmost sites to >500 g m−2 at the forest-tundra ecotone. Current observations and estimates of increases in total aboveground and shrub biomass with climate warming in the Arctic fall short of what would represent a 'subzonal shift' based on our spatial data. Non-vascular (moss and lichen) biomass is a dominant component (>90% of the photosynthetic biomass) of the vegetation across the full extent of arctic tundra, and should continue to be recognized as crucial for Earth system modeling. This study is one of only a few that present data on tundra vegetation across the temperature extent of the biome, providing (a) key links to satellite-based vegetation indices, (b) baseline field-data for ecosystem change studies, and (c) context for the ongoing changes in arctic tundra vegetation.Non peer reviewe

Floristic complexes on landslides of different age in Central Yamal, West Siberian Low Arctic, Russia

Accurate ground-based datasets are important for correct interpretation of remote sensing data. West-Siberian Arctic has been exposed to rapid land-cover and land-use changes during the last 50 years. Cryogenic  landslides  are important disturbing agents in the region, especially in the central part of the Yamal Peninsula. Different succession stages in the recovery of cryogenic landslides are described at the example of 4 model ones formed respectively in 1989, in the middle of 1970s, in late 1950s or early 1960s and an ancient landslide back scarp dated with radiocarbon method as ca 1000 year old. Botanical survey was performed in 1991 and repeated in 2012, phytosociological study on the same landslides and their surroundings was performed in 1997–2002. Correlation between different syntaxa, age and morphological element of landslide is shown. Both projective cover and species composition change gradually on young and old landslides, though vegetation on the ancient ones did not change during the last 20 years. Pioneer communities on Yamal landslides are dominated by grasses (Deschampsia borealis, Puccinellia sibirica, Calamagrostis holmii, Poa alpigena ssp. colpodea, Dupontia fisheri ).  Proportion of various species differs both between years and different sections of the shear surface. Сarex glareosa indicating saline deposits was recorded on landslides of all stages. Mosses play important role in the recovery and formation of organic horizon on the young landslides. Geochemical properties of the groundwater were analyzed and correlation of different communities with different levels of mineralization of groundwater is shown. Vegetation allows estimate the age of younger landslides and indicates the sites of possible ancient detachment

Applications of Local Floras for Floristic Subdivision and Monitoring Vascular Plant Diversity in the Russian Arctic

The local flora method has been used by Russian botanists for studying vast wilderness areas. The method strives to determine the total flora within a certain limited area and provides comparable data for spatial comparisons between different locations and temporal comparisons at the same location. Complete vascular plant diversity was sampled in 240 localities with an area between 100-300 km2 each throughout the Russian Arctic. These data were incorporated in a specially developed Integrated Botanical Information System (IBIS). This database provides a unique opportunity to study spatial gradients of different floristic variables. Pair-wise similarity of species composition and proportions of various phytogeographical groups in local floras were used in a floristic subdivision of the Russian Arctic. The floristic units derived by this method often resembled subprovinces of Yurtsev (1994), but there were also several areas of non-alignment. Application of local floras for monitoring of temporal changes has several constraints. However, nine local floras were re-visited 20-70 years after the initial survey. Increases in the number of Boreal and Hypoarctic species were recorded in the southern local floras. Standardized methods and the use of modern technical tools for accurate documentation could enable use of this approach at observatories across the Arctic.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Spatial patterns of arctic tundra vegetation properties on different soils along the Eurasia Arctic Transect, and insights for a changing Arctic

Vegetation properties of arctic tundra vary dramatically across its full latitudinal extent, yet few studies have quantified tundra ecosystem properties across latitudinal gradients with field-based observations that can be related to remotely sensed proxies. Here we present data from field sampling of six locations along the Eurasia Arctic Transect in northwestern Siberia. We collected data on the aboveground vegetation biomass, the normalized difference vegetation index (NDVI), and the leaf area index (LAI) for both sandy and loamy soil types, and analyzed their spatial patterns. Aboveground biomass, NDVI, and LAI all increased with increasing summer warmth index (SWI—sum of monthly mean temperatures > 0 °C), although functions differed, as did sandy vs. loamy sites. Shrub biomass increased non-linearly with SWI, although shrub type biomass diverged with soil texture in the southernmost locations, with greater evergreen shrub biomass on sandy sites, and greater deciduous shrub biomass on loamy sites. Moss biomass peaked in the center of the gradient, whereas lichen biomass generally increased with SWI. Total aboveground biomass varied by two orders of magnitude, and shrubs increased from 0 g m−2 at the northernmost sites to >500 g m−2 at the forest-tundra ecotone. Current observations and estimates of increases in total aboveground and shrub biomass with climate warming in the Arctic fall short of what would represent a 'subzonal shift' based on our spatial data. Non-vascular (moss and lichen) biomass is a dominant component (>90% of the photosynthetic biomass) of the vegetation across the full extent of arctic tundra, and should continue to be recognized as crucial for Earth system modeling. This study is one of only a few that present data on tundra vegetation across the temperature extent of the biome, providing (a) key links to satellite-based vegetation indices, (b) baseline field-data for ecosystem change studies, and (c) context for the ongoing changes in arctic tundra vegetation