Ultrastructural observations on five pioneer soil algae from ice denuded areas (King George Island, West Antarctica)

Morphological observations were made using transmission electron microscopy on five species of green soil algae, including Chlorosarcinopsis cf. gelatinosa Chantanachat & Bold, Muriella decolor visher, Tetracystis aeria Brown & Bold, Tetracystis pampae Brown & bold, and Stichococcus bacillaris Nageli. With an exception of the latter species, they are all new records in Antarctica. These species were the important pioneers in the colonization process of the areas recently denuded of ice. Collection of Muriella decolor was the first record from a soil habitat

Morphological and ultrastructural studies on Ulva flexuosa subsp. pilifera (Chlorophyta) from Poland

Ulva flexuosa subsp. pilifera (Kütz.) M. J. Wynne 2005 (= Enteromorpha pilifera Kützing 1845) was previously found in Argentina, the Czech Republic, Germany, Hungary, Romania, Slovakia and Sweden, recently also in Poland. The genus Ulva was first time described as Enteromorpha. Interestingly, Enteromorpha is used nowadays as a synonym for Ulva, a development which is based on molecular data. The morphologies of both young and mature specimens were studied, and most life cycle stages could be observed. Further, the formation of calcium carbonate crystals on the surface of Ulva thalli seems to influence the arrangement of the cells. A detailed ultrastructural (TEM) analysis of cell walls is presented. The TEM reveals in great details highly complex, irregular structures with stratification lines.The project was supported by funding from the Polish Ministry of Science, grant No. NN 304 013 437 and partially funded by the project GDWB-07/ 2011.822157163Acta Societatis Botanicorum Polonia

Morphology, ultrastructure and ecology of Muriella decolor (Chlorophyta) from subaerial habitats in Poland and the Antarctic.

This paper offers a comparison of Muriella decolor specimens from different geographical regions and habitats (limestone caves in Poland and ice denuded areas near the Ecology Glacier, King George Island, South Shetland Islands, West Antarctic). Morpho− logical and cytological variability, ecology and life strategies of M. decolor were studied in fresh samples, and also in cultures grown on agar plates. The complete life cycle, with de− tailed ultrastructural (LM and TEM) analysis are presented. The electron microscopic ob− servations prove that materials identified as M. decolor collected in Poland and the Antarc− tic have distinct ultrastructural features. These include the chloroplast lamella arrangement, mitochondrial cristae structure and the cell wall thickness

Diversity of Cyanobacteria on Limestone Caves

The caves are the biodiversity centers for different types of microorganisms, especially for cyanobacteria. They are also present in almost all extreme environments, and their importance in terrestrial ecosystems is greater because of the decreased competition from vascular plants. Cyanobacteria occurring on rocks are epilithic (colonizing the substrate surface), hypolithic (growing under pebbles and small stones), and endolithic (present in an upper layer of rock). There are three limiting factors for cyanobacteria growing in caves: light or its lack, high humidity, and constant temperature. In caves, one can find not only the cosmopolitan cavernicolous species but also rare taxa. Light, transmission, and scanning electron microscopy (SEM), laboratory cultures, as well as molecular phylogenetic studies are important tools in the study of cave cyanobacteria

Morphology, ultrastructure and ecology of Muriella decolor (Chlorophyta) from subaerial habitats in Poland and the Antarctic

This paper offers a comparison of Muriella decolor specimens from different geographical regions and habitats (limestone caves in Poland and ice denuded areas near the Ecology Glacier, King George Island, South Shetland Islands, West Antarctic). Morphological and cytological variability, ecology and life strategies of M. decolor were studied in fresh samples, and also in cultures grown on agar plates. The complete life cycle, with detailed ultrastructural (LM and TEM) analysis are presented. The electron microscopic observations prove that materials identified as M. decolor collected in Poland and the Antarctic have distinct ultrastructural features. These include the chloroplast lamella arrangement, mitochondrial cristae structure and the cell wall thickness

Morphology and ultrastructure of <i>Interfilum</i> and <i>Klebsormidium</i> (Klebsormidiales, Streptophyta) with special reference to cell division and thallus formation

<div><p>Representatives of the closely related genera, <i>Interfilum</i> and <i>Klebsormidium</i>, are characterized by unicells, dyads or packets in <i>Interfilum</i> and contrasting uniseriate filaments in <i>Klebsormidium</i>. According to the literature, these distinct thallus forms originate by different types of cell division, sporulation (cytogony) versus vegetative cell division (cytotomy), but investigations of their morphology and ultrastructure show a high degree of similarity. Cell walls of both genera are characterized by triangular spaces between cell walls of neighbouring cells and the parental wall or central space among the walls of a cell packet, exfoliations and projections of the parental wall and cap-like and H-like fragments of the cell wall. In both genera, each cell has its individual cell wall and it also has part of the common parental wall or its remnants. Therefore, vegetative cells of <i>Interfilum</i> and <i>Klebsormidium</i> probably divide by the same type of cell division (sporulation-like). Various strains representing different species of the two genera are characterized by differences in cell wall ultrastructure, particularly the level of preservation, rupture or gelatinization of the parental wall surrounding the daughter cells. The differing morphologies of representatives of various lineages result from features of the parental wall during cell separation and detachment. Cell division in three planes (usual in <i>Interfilum</i> and a rare event in <i>Klebsormidium</i>) takes place in spherical or short cylindrical cells, with the chloroplast positioned perpendicularly or obliquely to the filament (dyad) axis. The morphological differences are mainly a consequence of differing fates of the parental wall after cell division and detachment. The development of different morphologies within the two genera mostly depends on characters such as the shape of cells, texture of cell walls, mechanical interactions between cells and the influence of environmental conditions.</p></div

Relationships between diatoms and environmental variables in industrial water biotopes of Trzuskawica S.A. (Poland)

The heterogeneous nature and widespread anthropogenic impacts on industrial water biotopes in the Trzuskawica S.A., pose challenges to biomonitoring of this habitat. Generally, the concentration of trace elements in the industrial water biotopes reflects the anthropogenic impacts. With X-ray fluorescence method (TXRF) in waters 17 elements:P,S,Cl,K,Ca,Ti,Cr, Mn,Fe,Ni,Cu,Zn,Br,Rb, Sr, Ba, Pb were revealed. High amounts of Ca, from 300 ppm to 198 ppm in May and from 999 ppm to 231 ppm in September 2015, was determined. A total of 36 diatoms were found in two reservoirs and drainage ditch, but only three taxa: Cymatopleura radiosa, Navicula upsaliensis and Nitzschia angustata were present in all 7 sampling sites. These species are known to be tolerant to organic pollution, eutrophication, and also characteristic for limestone waters. The results of CVA showed that dintoms in the water reservoir stocked with fish were distinguished by highest species richness. The relationships between diatoms and environmental variables confirm the positive correlation with the currently functioning industrial plant (despite the increased water temperature and large content of trace elements). Our results suggest that, though heterogeneity in both diatoms and selected elements in industrial waters, diatoms can be useful indicators of habitat conditions