Figure - available from: Frontiers in Microbiology
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Effect of controlled desiccation and rehydration on the effective quantum yield (Y(II)) of PSII to five diatom cultures isolated from biocrusts in sand dunes (n = 4, only negative standard deviation is displayed for a better overview). Effective quantum yield values were standardized to the starting Y(II) to 100% for better comparison. The dashed line represents the measurement of relative humidity in the desiccation chamber.
Source publication
Terrestrial diatoms are widespread in a large variety of habitats and are regularly recorded in biocrusts. Although diatoms have long been known to live in terrestrial habitats, only a few studies have focused on their diversity of ecophysiology. Here we present a study on the ecophysiological performance of five terrestrial diatom cultures from bi...
Citations
... Most aero-terrestrial algal species are eurytherm and thus, the broad temperature tolerance of all three Streptofilum strains is in line with previous reports of other biocrusts algae Glaser et al. 2023). In terrestrial habitats, like soil surface or biocrusts, the environmental conditions can change more drastic and faster than in aquatic ecosystems, and consequently, broad temperature tolerance is required to thrive in those habitats. ...
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. Molecular and morphological characterisation including transmission electron microscopy confirmed that both new strains belong to Streptofilum . The Arctic strain is described as a new species, Streptofilum arcticum sp. nov., based on molecular differences, a specific sarcinoid morphology and unique ultrastructure with massive cell coverage composed of pili‐shaped scales. A comprehensive characterisation of the ecophysiological traits of both new Streptofilum isolates and the original one revealed a broad temperature tolerance, a rapid recovery of photosynthetic performance after desiccation, an efficient photosynthesis at low light and a tolerance to high‐light conditions. In addition, Streptofilum could cope with UV irradiation, but only S. capillatum grew under UV exposure. All Streptofilum strains are well‐adapted to water‐deprived terrestrial habitats such as biocrusts. From this study it can be concluded that already early‐branching streptophytes were able to tolerate terrestrial conditions.
