Celem pracy była analiza zróżnicowania gatunkowego oraz liczebności orzęsków planktonowych w układzie: rzeka - ekoton (woda/woda) - zbiornik retencyjny (Zbiornik Zemborzycki, Wschodnia Polska). Zarówno bogactwo gatunkowe jak i obfitość orzęsków planktonowych były wyraźnie zróżnicowane w poszczególnych badanych strefach. Najwyższą różnorodność i liczebność orzęsków stwierdzono w strefie ekotonowej. Najbardziej uboga jakościowo i ilościowo okazała się natomiast rzeka Bystrzyca. Niezależnie od strefy, w strukturze troficznej dominowały gatunki bakteriożerne, najniższy zaś udział miały gatunki glonożerne. Czynnikami w największym stopniu wpływającymi na występowanie protozoopłanktonu były stężenia w wodzie fosforu ogólnego, fosforanów oraz całkowitego węgla organicznego.

The aims of this study were to identify the taxonomic diversity and abundance of psammonic ciliate communities in mesotrophic and eutrophic lakes (Łęczna-Włodawa Lakeland, eastern Poland). The effect of selected physical and chemical water parameters on ciliates community was also analysed. Psammon samples were collected during three seasons: spring, summer and autumn of 2010. In each lake, in the psammolittoral, samples were collected in the euarenal, higroarenal, and hydroarenal zones. A total of 53 ciliate taxa were recorded. The highest value of the Shannon-Weaver index was recorded in summer in eutrophic lake (2.79). At the same time in mesotrophic lake, a lower value of the index was determined (0.79). The mean numbers of ciliates ranged from 516 ind.cm-3 in the eutrophic lake to 191 ind. cm-3 in the mesotrophic lake. In eutrophic lake, the highest number of ciliates was recorded in the euarenal (649 ind. cm-3), and the lowest in the higroarenal (425 ind. cm-3). In the mesotrophic lake, the highest average numbers were determined in the higroarenal (235 ind. cm-3), and the lowest in the hydroarenal (155 ind. cm-3). Irrespective of the lake trophy, Hymenostomata (Paramecium sp., Glaucoma sp., Uronema nigricans) occurred in the highest numbers (from 13 to 95%). The results demonstrated that N-NH4, P-PO4 and TOC can strongly regulate the abundance and taxonomic composition of ciliates. The strongest correlations between numbers of ciliates and physical and chemical water parameters were observed in the higro- and hydroarenal zones of the eutrophic lake.

The aim of the study was to specify the current status and direction of transformations of leaf beetle assemblages taking part in the rapid process of succession of vegetation towards the types of forest communities occurring in the Krzemionki Opatowskie reserve. At five sampling sites (in five plant associations) 30 species of Chrysomelidae were recorded. Five typical forest species (Chrysomela populi, Pyrrhalta viburni, Calomicrus pinicola, Altica brevicollis and Cryp-tocephalus labiatus) accounted for 16.67% of the number of species and 12.85% of the number of individuals caught in the reserve. The forest association richest in species (18) was Querco ro-boris-Pinetum (Que_Pin). This was followed by Tilio-Carpinetum association (Til_Car, 15 spp.), and then a mosaic of Tilio-Carpinetum and Querco roboris-Pinetum (Til_Car/Que_Pin), and Peucedano-Pinetum (Peu_Pin) (11 spp. each). The fewest number of species (10) were noted in Potentillo albae-Quercetum (Pot_Que). The most similar were the fauna of Potentillo albae--Quercetum (Pot_Que) and Querco roboris-Pinetum (Que_Pin) (55.08% similarity). The most distinct was the fauna of Peucedano-Pinetum (Peu_Pin). We can conclude that the structure of the leaf beetle assemblages in the forest associations studied in the reserve is at present an adaptive mixture of faunas characteristic of all the intermediate successional stages of vegetation, changing in this area in a relatively short time. The considerable diversity of fauna is the result of an ‘eco-tone in time’, i.e. the continuous presence of open-land species, which until recently had dominated here, accompanied by forest species characteristic of the current habitat types.