Cyanobacterial and green algal assemblages in various tundra habitats in the high Arctic (West Spitsbergen, Norway)

Abstract

The diversity of cyanobacteria and algae from various microhabitats in Spitsbergen is comparatively well known. However, the relationships between environmental factors and the structure of microflora communities remain largely unclear. This study was conducted in Hornsund Bay, which exhibits large variability in the physicochemical characteristics of habitats, particularly with regard to the availability of nitrogen and phosphorus. This variability, to a large degree, is caused by seabird colonies, which fertilize nutrient-poor terrestrial ecosystems near their nesting areas. The large variations in ecological conditions and vegetation types in the study area aid assessment of habitats representing different combinations of factors potentially influencing the formation of cyanobacterial and algal assemblages. The aim of this study was to examine the influence of physicochemical parameters on the taxonomic composition and diversity of green algae and cyanobacteria (particularly the coccoid, oscillatorialean, and heterocystous taxa). The study encompassed two groups of habitats – soil surface habitats and water-saturated habitats, both characterized by diverse influences of seabird colonies, vegetation cover, and moisture. Our results showed that taxonomic diversity and composition of cyanobacteria and algae were mainly influenced by P–PO<sub>4</sub><sup>3−</sup>, N–NH<sub>4</sub><sup>+</sup> and Ca<sup>2+</sup> (soil surface habitats), and NO<sub>3</sub><sup>−</sup>, as well as moisture (index of wetness) and pH (water-saturated habitats). The variability of these physicochemical properties was largely due to the variability of the seabird colony influence. Taken together, our findings aid in understanding the processes of formation of phycoflora assemblages in Arctic tundra.

Palynological Analysis of Surface Sediments in a High Arctic Pond, Revealing Desmids as Indicators of Wetlands and Climate Change

“…Our findings from the studied lake represent only eight species of Cosmarium from 457 with known ecological properties. Bioindication that was firstly implemented for Svalbard aquatic communities shows similar results of environment assessment, as were found previously in respect of water pH (Richter, 2018) and for close related well studied regions such as Kola Peninsula (Denisov and Barinova, 2015), where there were found 16 species of Cosmarium as bioindicators of similar environmental conditions. Four of them were found in Svalbard also.…”

“…The high relative abundance of C. punctulatum could be due to its wide range of pH tolerance because it has been reported from slightly acidic to alkaline habitats. However, C punctulatum has been recovered from a lake in Hornsund with pH 7.3 (Richter et al, 2018). The desmid assemblage record from snow samples and moss patches along the rim of ponds situated on the coast in Ny-Alesund includes the forms C. botrytis, C. crenatum, and C. granatum that are present in the surface sediments (Lenzenweger and Lütz, 2006).…”

“…The primary producers are directly affected by changes in the physical environmental factors such as light, temperature, etc. (Richter, 2018). The study of the biota of these ponds is, therefore, crucial to understand recent abrupt warming of the Arctic region and the impact of these changes on the ecosystem.…”

The impact of marine vertebrates on polar terrestrial invertebrate communities

“…Complete and lush vegetation cover is commonly observed along such slopes, apart from sites very close to the base of the bird cliffs or within the colony itself, where mechanical disturbance by falling rock debris and nest material, trampling activity and excess guano input is experienced (Eurola and Hakala 1977;Hodkinson et al 1994;Zmudczyńska et al 2008;Zmudczyńska-Skarbek et al 2013;Zwolicki et al 2020). A band of unstable ground immediately adjacent to the base of large, densely-occupied bird cliffs may be completely devoid of vegetation (the zone described as 'sterile' by Odasz 1994), or only sparsely colonised by a very few nitrophilous, relatively fast-growing vascular plant species such as Cochlearia groenlandica and Poa alpina (Zwolicki et al 2016a), and patches of algae and cyanobacteria (Richter et al 2018). Such poorly vegetated habitat found at the foot of Gnålberget cliff (Hornsund) was colonised by a single springtail species, Megaphorura arctica (Zmudczyńska et al 2012).…”

Polar terrestrial ecosystems: ecology, diversity, and biogeography

“…Various kinds of organisms interact with their environments at different levels. Richter et al [11] describe how the structure of cyanobacterial and algal assemblages depends on correlative physicochemical factors in the high Arctic tundra habitats.…”