Microinvertebrates play a role as top consumers on glaciers. In this study we tested what kind of cryoconite material the animals inhabit (mud vs granules) on the edge of the Greenland ice sheet (GrIS) in the south-west. We also tested the links between the densities of micro-fauna in cryoconite material and selected biotic (algae, cyanobacteria, bacterial abundances) and abiotic (water depth, pH, ion content, radionuclides) factors. We collected 33 cryoconite samples. Tardigrada and Rotifera were found in 18 and 61% of samples, respectively. Invertebrates in this study were considerably less frequent and less abundant in comparison with High Arctic glaciers. The highest density of tardigrades and rotifers constituted 53 and 118 ind./ml, respectively. Generalized linear models showed no relationship between the densities of fauna and biotic and abiotic factors. The densities of animals were significantly higher in granules than in mud. The difference in the densities of animals between granules and mud reflects a simple mechanistic removal of invertebrates from the sediment during its erosion by flushing which leads to mud formation. These processes may influence a random distribution of micro-fauna without clear ecological interactions with biotic and abiotic variables at the edge of the GrIS.

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The methods of separation of microalgae has a significant impact in the economic aspects of their cultivation. in this study, pine bark was used as a substrate for immobilization of microalgal biomass cultivated in raw municipal sewage. the experiment was conducted in cylindrical photobioreactors (PBRs) with circulation of wastewater. Biomass was cultivated for 42 days. After that time, abundant growth of the biofilm with microalgae on the surface of pine bark as well as improvement of the quality of treated sewage were observed. The efficiency of removal of nutrients from wastewater was 64-81% for total nitrogen and 97-99% for total phosphorus. Moreover, the concentration of suspended solids in sewage was reduced, which resulted in a decrease in turbidity by more than 90%. Colorimetric analysis and Volatile Matter (VM) content in the substrate showed a decrease in the Higher Heating Value (HHV) and concentration of VM due to the proliferation of biofilm.

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–PO₄³⁻, N–NH₄⁺ and Ca²⁺ (soil surface habitats), and NO₃⁻, 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.

This article describes the morphological characteristics of the populations of green alga, Tetraspora gelatinosa, growing in the stressful Arctic conditions (77°00'22" N, 015°32'54.33" E). We present the first detailed morphological characteristics of this spe− cies from such a high latitude. Populations from both stagnant and flowing waters were studied. Depending on the type of habitat, their mucilaginous colonies (thalli) have differ− ent shapes, but the structure, size and the placement of the vegetative cells, akinetes and ameboid forms, as well as the pseudocilia morphology of both populations, were very simi− lar. Literature data on the distribution of T. gelatinosa indicate that it is a cosmopolitan spe− cies. Our data are compared with some characteristic features of this species growing in dif− ferent geographical and climatic zones. No significant differences were found in the mor− phology of the colonies compared, nor in the location and the inner structure of cells. How− ever, there were slight differences in cell size between the populations from warm and cold zones.

The process of growth of algae can be described using the images from microscopic analysis. The new approach to assessment of the growth dynamics of algae used the data of granulometric composition of liquid medium and the modified Avrami equation relating to the crystallisation process. This paper presents a comparison of both methods (granulometric and microscopic) for the analysis of the dynamics of changes in the growth of algae in wastewater. The experimental set-up consisted of four glass tanks filled with biologically treated sewage, in which algae grew. The cultivation of algae was carried out for 8 weeks. During this period, the granulometric analysis and microscopic observations of sewage were conducted. The study demonstrated that with increase in the size of flocs in treated sewage, biomass of algae was also increased. Therefore, the results obtained with the method of laser diffraction are in agreement with microscopic observation of flocs. Granulometric analysis could be, next to microscopic analysis, a method for the estimation of the dynamics of changes in the growth of algae in sewage. This knowledge will allow to selection of a suitable method of wastewater treatment and algal separation.