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The distribution and ecology of Chara braunii Gmellin 1826 in Poland is described, based on herbaria collections, literature data and own investigations. Maps showing the distribution of Ch. braunii are presented, as well as a list of localities with brief descriptions of the habitats. Additionally, some remarks on the distribution limit in the northern hemisphere are given.
The fossil Charophyta from the Devonian sediments of Spitsbergen are here described for the first time and classified to the species rank on the basis of thin sections.
Ultrastructural changes of manubria of Chara vulgaris during spermiogenesis were studied. The changes (as compared to the antheridial filament proliferation stage) involve thickening of the content of secretive vesicles and changes in their consistency, the disappearance of rough endoplasmic reticulum (ER) and appearance of smooth ER, increases in the number and size of plastoglobules in plastids, condensation of mitochondria, and significant cell vacuolization. Autoradiography with 3H-fucose pulse incubation showed that during spermatogenesis it was incorporated into the manubria. Their radioactivity decreased after 2 h postincubation in nonradioactive fucose during spermiogenesis. This was not observed during proliferation of antheridial filament cells. It is suggested that polysaccharide secretion into the internal antheridial space increases during spermiogenesis, perhaps connected with the thickening of secretive vesicle content observed by electron microscopy.
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The distribution and ecology of charophytes in Lubelszczyzna (Eastern Poland) is described based on herbaria collections, literature data, and the author’s own investigations. Maps showing the distribution of all 22 charophyte species identified so far are presented, as well as the details of habitats ecology. Some data on species frequency, conservation, and threats are added.
This paper presents recent localities of charophytes in the peatland complex of the northern part of Noteć Forest (Wielkopolska, Poland). In alkaline or calcareous fens and shallow waters, seven species of charophytes were found: Chara globularis, C. intermedia, C. virgata, C. vulgaris, Nitella capillaris, N. mucronata and N. syncarpa. Some of the charophytes, which were observed in this area, are regarded as endangered and vulnerable in Poland, especially, C. intermedia, N. capillaris and N. syncarpa. The preliminary research results on the studied charophyte distribution and ecology are presented.
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