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EN
The studies on bentic diatoms were conducted in 2009–2011 at eight samplings sites over the Żołynianka stream and its tributary, the Jagielnia. 427 diatom taxa were recorded in total. Achnanthidium minutissimum var. minutissimum, Aulacoseira ambigua, Fragilaria capucina var. capucina, Gomphonema parvlum, Navicula gregaria, Nitzschia palea and Planothidium lanceolatum were dominant taxa in both watercourses. Chemical analysis of water showed high chemical status of water at most of sampling sites. The results of diatomaceous analysis conducted with OMNIDIA software revealed moderate and poor condition of water. The best water quality was recorded in the Jagielnia stream (good or moderate status). The values of the analyzed indices showed the worst water quality on the Żołynianka at site four, showing bad ecological status. TDI index deviated the most from the other two indices (IPS and GDI), always indicating poorer water quality.
EN
Diatoms Bacillariophyceae are a specialized, systematic group of algae, living in different types of ecosystems, and they are very good indicators of water quality. Recently, detailed studies have been carried out in the territory of the Podkarpacie Province on the diversity of diatoms in running waters. The area of study covers mostly the catchment of the biggest rivers of the province (mainly the Wisłok River) and cultivated soils. Running waters in the Podkarpacie Province are characterized by a huge species richness of diatoms, 738 different taxa have been found so far. The highest number of taxa was noted in the Wisłok River (400), while the Żołynianka and Różanka streams and the Mleczka were also characterized by huge diversity (from 200 to over 350 taxa). In the majority of studied sites diatoms of alkaline (pH>7) and nutrient rich (eutrophic) waters dominated: Navicula lanceolata, N. gregaria, N. capitatoradiata, Nitzschia palea, N. dissipata ssp. dissipata, Achnanthidium minutissimum var. minutissimum, A. pyrenaicum, Amphora pediculus, Diatoma vulgaris, Rhoicosphenia abbreviata, Planothidium lanceolatum, Cocconeis pediculus and C. placentula var. lineata. About 150 taxa were indentified on cultivated soils, among which the largest populations were formed by Hantzschia amphioxys, Mayamaea atomus, Nitzschia palea, N. pusilla, Pinnularia obscura and Stauroneis thermicola.
EN
The Baryczka stream is a small (about 20 km long), left bank tributary of the River San (Podkarpackie Voivodeship). Studies on diversity of diatom communities using OMNIDIA software were conducted in 2010 and 2011. Diatomaceous indices IPS, GDI and TDI and Van Dam et al. classification system were used for water quality assessment. Planothidium lanceolatum, Cocconeis placentula var. lineata, Achnanthidium minutissimum var. minutissimum, Nitzschia linearis, Rhoicosphenia abbreviata, Navicula lanceolata and Naicula gregaria were the most numerous. Values of the IPS index indicate good water quality (II–III class). Based on the GDI index, waters of the Baryczka stream were classified to III class water quality. The TDI index indicated poor and bad ecological state on the most sampling sites. On all sampling sites alaliphilous (pH>7) diatoms taxa predominated. The most common were eutraphentic and hypereutraphentic diatoms. With respect to trophy, it was shown that α- and β-mesosaprobous diatoms were the most common (III and II class water quality).
EN
Analyses of diatom assemblages were performed in sediment cores from the Szczecin Lagoon area, as a part of a multidisciplinary research including seismoacoustic profiling and different types of palaeoecological and geological analyses: palynological, macrofossil, malacological, lithological, geochemical and sedimentological. Changes in the composition of a large spectrum of species of the local fauna and flora allowed the reconstruction of environmental conditions during the Late Glacial and Holocene in the Szczecin Lagoon. Succession of the diatom communities is the main topic of the present paper. In the Late Glacial sediments, the diatom flora was scarce and occurred only in core 42/99. In other cores, diatom assemblages characteristic for three phases of the Holocene development (limnic-swampy, marine/brackish-water and lagoonary) of the Szczecin Lagoon were distinguished. The Late Glacial (Older-Dryas (?), Allerod and Younger Dryas) record is incomplete and the flora is predominantly represented by Actinocyclus normanii, Aulacoseira spp, Cocconeis placentula, and Fragilaria brevistriata. The oldest Holocene sediments of the limnic-swampy type, are characterised by freshwater and halophilous diatoms (e.g. Fragilaria brevistriata, Cocconeis placentula and Stephanodiscus hantzschii). In the overlying marine sediments, only occasionally brackish-water taxa (e.g. Planothidium delicatulum, Cocconeis hauniensis) were observed. In the uppermost deposits formed in lagoonary conditions freshwater, halophilous and brackish-water species dominated (e.g. Aulacoseira granulata, Cavinula scutelloides and Epithemia turgida).
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