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EN
The Bełchatów lignite deposits are a rich archive allowing palaeoenvironmental, palaeoecological and palaeoclimatic reconstructions from the Neogene and Quaternary periods. We describe the results of palynological studies (including non-pollen palynomorphs) of eight samples from the lower Miocene KRAM-P 211/214 collection of plant macroremains. The results of this palynological analysis are consistent with the results of previous studies of plant macroremains and significantly enrich our knowledge of vegetation and palaeoenvironment. Both studies indicate the presence of a freshwater body (a moderately large and deep lake) surrounded by wetland vegetation (including swamp forests with Glyptostrobus, Taxodium, Nyssa and Osmunda) and upland mesophytic forests. Evergreen or at least semi-evergreen forest communities grew along the ancient shores of the lake and on the slopes of the Mesozoic calcareus rocks surrounding the lake. In the lake, green algae (Pediastrum, Tetraedron and some Botryococcus) and freshwater peridinoid dinoflagellates were major components of the algal community. The same lake was the source of previously identified animal remains: freshwater fishes, molluscs, and mammals, including Megachiroptera bats. Our analysis shows that the climate was subtropical and humid, with an estimated mean annual temperature of 16.8–17.8°C.
EN
KopyrinaA total of 437 species (453 with infraspecific taxa) of algae and Cyanobacteria were identified in 2034 samples collected during the first research on nine thermokarst lakes in Yakutia carried out in 1986–1994 and 2001–2015. The richest algal flora was determined in Lake Aalah, represented by 241 taxa. Bacillariophyta species dominated in four lakes, whereas Chlorophyta and Cyanobacteria dominated in the others. The algal bioindication demonstrated preferences for benthic and plankticbenthic life, temperate temperature, low alkalinity, waters with moderate oxygenation, low to medium enrichment with chloride, low organic pollution, and mesotrophic state. Comparative floristic, CANOCO and JASP statistical methods divided the species and environmental variables into groups of lakes related to landscape terraces. Local landscape positions and high summer water temperatures may play a major role in the formation of algal flora. The index of algae taxa per area stabilized at about 70 species per km2. The highest polymorphism of algae floras, defined by the Subspecies/Species Index, was determined for the lakes of the Tungulunskaya terrace: Lake Ynakh, Lake Nal Tungulu and Lake Tungulu (1.041–1.058), and the average total flora was 1.036. Our results can help in monitoring and protecting the ecosystems of thermokarst lakes in Yakutia in the harsh climate environment of Northeastern Eurasia.
EN
We identified 209 species of algae and cyanobacteria at 4 sites in the Kabul River. Green algae, diatoms, and charophytes dominated in the river, which reflects regional features of agricultural activity. Species richness and algal abundance increased down the river. The Water Quality Index characterizes the quality of water down the river as medium to bad. The index of saprobity S reflects Class III water quality. The Water Ecosystem Sustainability Index (WESI) shows contamination with nutrients. According to the River Pollution Index (RPI), waters in the river have low alkalinity and low salinity, and are contaminated with nutrients. Pearson coefficients showed that water temperature plays a major role in the total species richness distribution (0.93*) and in the green algae distribution (0.89*), while cyanobacteria were stimulated also by water salinity (0.91*). Stepwise regression analysis indicated water temperature as the major regional factor that determines riverine algal diversity. Surface plots and Canonical Correspondence Analysis (CCA) showed that salinity, nitrates, temperature, and Biochemical Oxygen Demand (BOD) can be defined as major factors affecting algal diversity. Dendrites mark the upper site of the Warsak Dam as the source of the community species diversity. Bioindication methods can give relevant and stable results of water quality and self-purification assessment that can be employed to monitor the regional water quality.
PL
W pracy przedstawiono wyniki badań wpływu temperatury na wydajność produkcji biomasy alg słodkowodnych. Laboratoryjną hodowlę prowadzono w szklanych bioreaktorach cylindrycznych w temperaturze 26, 28 oraz 30°C. Zawartość biomasy w podłożu hodowlanym oznaczano metodą wagową. Najwyższą efektywność przyrostu biomasy uzyskano prowadząc hodowlę alg w temperaturze 28°C. Wzrost temperatury do 30°C nie powodował zwiększenia produktywności biomasy.
EN
The paper presents the influence of temperature on the efficiency of freshwater algae biomass production. Laboratory culture was carried out incylindrical glass bioreactors at 26, 28 and 30°C. The content of biomass in the culture medium was determined by dry weight measurement. The highest efficiency of algae biomass growth was obtained at 28°C. The incrase of biomass production with the rise of temperature to 30°C was not observed.
EN
A new palaeopalynological investigation was conducted on 15 samples from four test-pits at the Gray Fossil Site (Bear Pit, Elephant Pit, Test Pit 2-2010, and Rhino Pit). In total, 50 morpho-species of miospores (including five species of spores, eight species of gymnosperm pollen, and 37 species of an giosperm pollen) and 18 morpho-species of fresh water algal micro-remains were identified. One new morphological species, related to zygospores of the Zygnemataceae, Stigmozygodites grayensis sp. nov., is proposed. The assemblage of fossil algae recovered provides in sights into the palaeoenvironmental conditions of the uppermost (125 cm) part of the Gray Fossil Site sedimentary cover, deposited after the formation of a number of sink holes, and the fill of the palaeosinkholes. Most of the algae identified prefer meso- to eutrophic conditions and are characteristic of stagnant to slowly flowing shallow fresh water. Therefore, the lacustrine fossiliferous sediments at the Gray Fossil Site represent pond deposits. The palaeopalynological analysis revealed differences in the composition of the miospore and algal assemblages of the pits studied, suggesting that the Test Pit 2-2010, Bear, and Elephant pits are similar and may have been formed in the same pond, while the presence of a higher percentage of algae in the Rhino Pit may indicate sedimentation in a separate waterbody.
EN
Pollen analysis of 16 samples of coaly sediments taken from one of sinkholes developed within the Triassic limestones cropping out at Tarnów Opolski, Upper Silesian Upland has been done. The study revealed a taxonomically rich assemblage of excellently preserved sporomorphs (pollen grains and spores) as well as microfossils of fresh-water algae (mainly Chlorophyta). The pollen analysis made it possible to reconstruct a vegetation growing during sedimentation of deposits filling the studied sinkhole and clear facies succession, from open aquatic (with abundant fresh-water algae) to marshy one (e.g. swamp forests composed of Taxodium, Nyssa and Alnus). Riparian forests dominated by deciduous trees, e.g. Pterocarya, Carya and Liquidambar, grew on wet terrains surrounding the water body. Drier elevated terrains were overgrown by mixed mesophytic forests with small admixture of thermophilous plants. Results of the pollen analysis indicate that during the sedimentation of the sinkhole filling the climate was warm temperate and moderately wet. Recorded sporomorphs and a mutual ratio of arctotertiary and palaeotropical taxa point at a Middle Miocene age of the studied deposit.
8
Content available remote Manganese accumulation by two species of Chara
EN
This paper reports the results of Mn accumulation in two species of green algae: Chara globularis and Chara hispida. The results of laboratory and field experiments show a rapid accumulation of Mn by charophytes and demonstrate that deposit formation on the plant surface in the so-called adsorption phase occurs in Mn accumulation. Both species can be an important factor in Mn circulation in lakes.
EN
Pollen grains, spores and phytoplankton from the Neogene succession of a borehole at Józefina (northern part of the Kraków–Silesia Upland, Poland) have been studied. The composition of the pollen spectra and the mutual ratio of palaeotropical and arctotertiary elementssuggest a Late Miocene age. Among the pollen grains, there are significant elements characteristic of riparian forests (Pterocarya, Caryaand Liquidambar) and mixed mesophytic forests (Pinus, Fagus and Carpinus). Such a pollen and spore association suggests a temperateand mid-wet climate, cooler than during the Early and Mid Miocene period, but still warmer than the present-day climate of Poland. Thismakes the pollen-spore association from Józefina comparable with XII climatic phase represented by the Carpinipites-Juglandaceaespore-pollen zone. The occurrence of aquatic plants and freshwater algae (e.g., Sigmopollis, Zygnemataceae and desmids) indicates alacustrine palaeoenvironment.
EN
The Zygnemataceae are an extant family of freshwater filamentous green algae which produce acid-resistant zygospores. Palynomorphs of probable zygnematacean affinity occur in sediments of the Carboniferous to Holocene age (van Geel & Grenfell, 1996). These algae reproduce using four types of spores, but only zygospores and probably aplanospores are acid-resistant and can be preserved in the fossil record. The majority of recent species have zygospores of constant form of three types: elliptical (occurring in genera Debarya and Spirogyra), square (occurring in Mougeotia) or circular (occurring in Zygnema). The zygospores normally have a three-layered wall (exospore, mesospore and endospore), but only mesospore contains a decay and acid-resistant substance (most probably algaenans), so usually only this layer is preserved in fossil state, and is of interest to palynologists. The mesospore layer is smooth or ornamented with various sculptures (Kadłubowska, 1972; Grenfell, 1995). The shape and sculpture are very important features for determination of both the recent and fossil species. Two samples from the Bełchatów Lignite Mine were palynologically examined and two types of probable fossil zygnematacean zygospores, differing in shape, were encountered. The following species have been distinguished: Tetraporina sp., Spintetrapidites quadriformis Krutzsch & Pacltová as well as Ovoidites elongatus (Hunger) Krutzsch, and O. ligneolus Potonié ex Krutzsch. The fossil genus Tetraporina is usually related to the recent zygnematacean algae zygospores of Mougeotia genus, fossil Ovoidites is the nearest the recent zygospores of Spirogyra and Sirogonium, while Spintetrapidites is similar to both zygospores of Zygnemataceae and Tetraedron green algae. Species of recent genera Mougeotia and Spirogyra are usually found in shallow, freshwater, oxygen-rich environments such as ponds, lake margins (paludal or low gradient fluvial), ditches and very slowly moving streams (Kadłubowska, 1972). Occurrence of Tetraporina and Ovoidites zygnematacean zygospores in the material studied from Bełchatów points out at presence of water basin(s) during sedimentation time. That confirms the previous geological results that formation of examined sediments took place in the environment of a meandering river (including ox-bow lakes).
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