New Strains of the Deep Branching Streptophyte Streptofilum: Phylogenetic Position, Cell Biological and Ecophysiological Traits, and Description of Streptofilum arcticum sp. nov.

Streptofilum capillatum was recently described and immediately caught scientific attention, because it forms a phylogenetically deep branch in the streptophytes and is characterised by a unique cell coverage composed of piliform scales. Its phylogenetic position and taxonomic rank are still controversial discussed. In the present study, we isolated further strains of Streptofilum from biocrusts in sand dunes and Arctic tundra soil.

Role of Climate and Edaphic Factors on the Community Composition of Biocrusts Along an Elevation Gradient in the High Arctic.

Biological soil crusts are integral to Arctic ecosystems, playing a crucial role in primary production, nitrogen fixation and nutrient cycling, as well as maintaining soil stability. However, the composition and complex relationships between the diverse organisms within these biocrusts are not well studied. This study investigates how the microbial community composition within Arctic biocrusts is influenced by environmental factors along an altitudinal gradient (101 m to 314 m).

Resurrection of a diatom after 7000 years from anoxic Baltic Sea sediment.

Dormancy is a wide-spread key life history trait observed across the tree of life. Many plankton species form dormant cells stages that accumulate in aquatic sediments and under anoxic conditions, form chronological records of past species and population dynamics under changing environmental conditions. Here we report on the germination of a microscopic alga, the abundant marine diatom Skeletonema marinoi that had remained dormant for up to 6871 ± 140 years in anoxic sediments of the Baltic Sea and resumed growth when exposed to oxygen and light.

Chytrid fungi infecting Arctic microphytobenthic communities under varying salinity conditions.

This study aimed to investigate the presence and diversity of fungal parasites in Arctic coastal microphytobenthic communities. These communities represent a key component in the functioning of Arctic trophic food webs. Fungal parasites, particularly Chytridiomycota (chytrids), play significant roles by controlling microalgal bloom events, impacting genetic diversity, modifying microbial interactions, and accelerating nutrient and energy transfer to higher trophic levels.