Irena Bielańska-Grajner

The psammic rotifer structure in three Lobelian Polish lakes differing in pH

Thirty five species of rotifers were found in the psammon of three lakes of differing pH in open water. The largest number of rotifer species and their highest abundance was found in lake Rekowskie which had a slightly acid to neutral water pH. The lowest quantity and the number of rotifers species were observed in the lake with lowest pH. The results suggest that pH is one of the most important factors affecting the number and diversity of psammic rotifers in these lakes.

The influence of biotic and abiotic factors on psammic rotifers in artificial and natural lakes

The effect of sand grain size, porosity and the abundance of algae on the community structure of psammic rotifers was tested in three anthropogenic lakes (Upper Silesia) and compared with three natural ones (West Pomerania). The structure of grain size in the studied beaches of artificial and natural lakes was similar but differences were found in the abundance of algae. The structure of the psammic rotifer community in Upper Silesian lakes was different from natural lakes in West Pomerania. The structure of psammic rotifer communities in anthropogenic reservoirs and lakes (West Pomerania) differed in numbers of species and numbers of psammobiont species, and also diversity index. The most altered structure of rotifer assemblages was observed in the psammon rotifers of the strongly contaminated Dzierzno Duze Lake.

The biodiversity of psammon rotifers in Włocławek Reservoir

The biodiversity of psammon rotifers in Włocławek Reservoir In total 47 rotifer taxa were found in the psammon of Włocławek Reservoir; 36 at the site in Dobiegniewo and 38 at Dobrzyń. Five species were classified as psammobionts, 14 as psammophiles, and the remaining ones as psammoxens. Psammobionts and psammophiles were observed mostly in the psammon at Dobiegniewo. The highest density of psammon rotifers was noted in the euarenal zone of the flooded part of the reservoir. However, the highest density in the area near the swift current was noted in the hygroarenal zone. While the flooded part of the reservoir had four dominant species of rotifer: Lecane closterocerca, L. scutata, Lepadella patella and Cephalodella catellina, the area near the swift current had only two: Cephalodella catellina and Brachionus quadridentatus. The most favorable conditions for the development of psammon rotifers was in the flooded area of the reservoir. In comparison with other dam-reservoirs in Poland, the community of these rotifer types in the Włocławek Reservoir was characterized by considerable species richness.

Biodiversity of rotifers in urban water reservoirs of Southern Poland

Abstract Rotifer diversity was studied in three different types of artificial water bodies situated in one of the largest cities in Poland. The bodies of water were as follows: a fountain in a city park, the Nowa Huta dam reservoir, and the Bagry gravelpit. The lowest number of rotifer species (23) was noted in the urban fountain, and the highest (36) in the Bagry gravel-pit lake. Rotifers’ communities in the investigated water reservoirs showed different levels of diversity and density. The most numerous species in the dam reservoir was Trichocerca similis (2511 ind. l-1) and in the Bagry gravel-pit lake was Polyarthra dolichoptera (2634 ind. l-1). However, the most abundant species in the fountain was Brachionus urceolaris (863 ind. l-1). The highest values of Shannon and evenness diversity indices were found in the Bagry gravel-pit lake (H’ = 2.521, J’ = 0.783), while the lowest in the urban fountain (H’ = 0.568, J’ = 0.258). The DCA analysis (Detrended Correspondence Analysis) showed that the diversity of rotifers communities in the studied reservoirs was related to the concentration of magnesium and calcium, and to water conductivity.

Bdelloidea (Rotifera) from the Tatra National Park, with some species newly found in Poland

In comparison to a substiantial body of information on monogonont Rotifera, there has been relatively little work on the bdelloid biogeography in Poland. Of the 450 species known in the World only 85 were recorded in Poland and 31 - in the Tatra Mountains until 2007. Elaboration of samples taken from different habitats: water, moss, lichens and litter, and tree lichens in the Tatra National Park in July 2008 revealed 23 taxons of Bdelloidea, 14 of which had not previously been found in the rotifer fauna of Poland..

Is zooplankton an indicator of the water trophic level in dam reservoirs

Abstract The trophic state of ten dam reservoirs was assessed using a zooplankton community. In order to determine the trophic state of dam reservoirs, we used indices calculated on the basis of density and species structure of Rotifera and Crustacea communities. Samples were collected once during summer 2012 in ten dam reservoirs. The largest numbers of zooplankton taxa were found in a lowland high meso-eutrophic dam reservoir (Koronowski) and the lowest ones in a submontane low eutrophic dam reservoir (Lubachowski). The trophic state was determined for the investigated dam reservoirs. In the case of the Rotifera community, the percentage of the tecta form in the Keratella cochlearis population and the proportion of high-trophic species in the total species density were the best indices to describe the water trophic status. In the case of the crustacean community, the best indices were the density of Crustacea and the biomass of Cyclopoida. The high value of all indices calculated on the basis of density and species structure of Rotifera and Crustacea was determined for Zygmunt August Lake, whose trophic status was defined as highly eutrophic to polytrophic. Our study has shown that zooplankton could be a good ecosystem indicator of the water trophic level in dam reservoirs.

Ecology of moss-dwelling rotifers in a raised bog: Differentiation of rotifer communities in microhabitats

Abstract Peat bogs play key roles in preserving the stability of ecological relationships, but are some of the fastest disappearing and most endangered ecosystems in Europe. The aims of this study were: (1) to compare the distribution, species richness, diversity, and density of rotifers in microhabitats of a raised bog; and (2) to verify the hypothesis that rotifer density and species composition are dependent on seasonal factors, moss moisture content, and the dominant species of mosses in the microhabitats. Sampling was done monthly from April to November in 2013–2014 in the bog Moszne in eastern Poland (51°27′28.7″ N, 23°07′15.8″ E). The microhabitats sampled included hummocks, slopes, and hollows. A total of 40 rotifer taxa were identified. The highest species richness occurred in the hollows (40), dominated by Sphagnum angustifolium. Markedly lower numbers of taxa were observed on the slopes (28) dominated by Sphagnum magellanicum and Sphagnum rubellum, and in the hummocks dominated by S. magellanicum and Polytrichum sp. During the entire study period all the studied microhabitats were dominated by the Bdelloidea: Habrotrocha angusticollis, Habrotrocha lata, Habrotrocha sp., Dissotrocha macrostyla, Philodina sp. as well as Rotaria rotatoria and Rotaria tardigrada. The greatest species diversity of rotifers was recorded in the hollows (diversity index H′ = 2.307) and the smallest in the hummocks (H′ = 0.769). The density of rotifers was also the highest in the hollows. Statistically significant differences in densities of rotifers between the microhabitats were found (Kruskal–Wallis test: H′(2, n = 33)= 10.33, P = 0.005). The greatest diversity of rotifers and the greatest density were observed in spring.