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Zmienność przebiegu zjawisk lodowych na Bugu w latach 1903–2012

Bączyk A., Suchożebrski J.

Inżynieria Ekologiczna

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2016

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Nr 49

136--142

PL

W artykule dokonano analizy wyników obserwacji przebiegu zjawisk lodowych na Bugu, prowadzonych w latach 1903–1960 oraz 2001–2012 w przekrojach wodowskazowych Dorohusk, Włodawa, Frankopol i Wyszków. Ustalono, że czas trwania zjawisk lodowych uległ skróceniu. Wyraźne są fluktuacje czasu trwania zjawisk lodowych i zlodzenia rzeki związane przede wszystkim ze zróżnicowaniem warunków termicznych w sezonach zimowych. Artykuł jest wprowadzeniem do tematyki zjawisk lodowych występujących na rzekach we wschodniej części Polski, a także przyczynkiem do prowadzenia dalszych badań związanych ze zlodzeniem rzek oraz do poznawania procesów je kształtujących.

EN

The article describes an analysis of observations of ice phenomena on the Bug River, conducted between 1903– 1960 and 2001–2012, on representative gauge stations – Dorohusk, Włodawa, Frankopol and Włodawa. It has been concluded that the length of the period of ice phenomena has decreased. Fluctuations of duration of ice phenomena and ice cover, which are related to differentiation of temperature conditions in winter season, are well-marked. The article is an introduction to the subject of ice phenomena on the rivers in eastern part of Poland, as well as, the cause to pursue further research related to the ice cover of rivers and to explore the processes shaping them.

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Aquatic mollusc communities in riparian sites of different size, hydrological connectivity and succession stage

Jurkiewicz-Karnkowska E.

Polish Journal of Ecology

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2008

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Vol. 56, nr 1

99-118

EN

The aim of the present study was to describe the diversity and abundance of the mollusc communities in long and diverse series of riparian water bodies (59 in total) and to compare them with previous (two years before) studies based on much shorter series of sites (21 in total). An attempt was made to check whether the previous analysis of mollusc groupings is suitable to the classification of the riparian sites of a large area. The studies were carried out in the years 2004-2006 in left-bank part of the valley between 53 and 152 km of the course of the lowland medium sized natural river (Bug River, Eastern Poland) in 59 water bodies differing as regards size (from about 0.01 to a few ha), location in the valley, hydrological regime and successional stage. The samples were collected from the bottom (with dredge) and from macrophytes. The high species richness and diversity were found within the study area despite that the natural floodplain fragments were quite small (about 10% of the whole investigated fragment of the river valley). 52 mollusc species were noted: 36 snails and 16 bivalves (over 50% more than in the preliminary series). Relatively rich malacofauna existed in larger and younger water bodies, as well as in some temporary ones, but located in the active floodplain. Species diversity of individual habitats was comparable to that reported from the earlier study (Jurkiewicz-Karnkowska 2006), i.e. H' values amounted to 2-3 in most cases. However, there were more cases where H' values exceeded 3, as well as H' values were higher at larger scale, i.e. site groups and the total study area (3.5-4.5). The most common species (F [Greater-than or equal to] 50%) within the investigated area were Lymnaea stagnalis, Bithynia tentaculata, Planorbarius corneus, Anisus vortex, Radix balthica and Viviparus contectus. The most frequent species usually constituted significant components of mollusc communities of individual water bodies. The only species with percentages exceeding 10% of total mollusc abundance at the scale of the study area were P. corneus and L. stagnalis. The abundance of molluscs was of the order of several to a few hundred individuals per sample (0.5-1 m[^2] of bottom). Basing on the occurrence of molluscs in the investigated habitats I-V groups of water bodies were distinguished applying multivariate analysis. They differed in abundance, dominance pattern and diversity of malacocoenoses, as well as frequencies of individual species. Especially high distinctness of malacocoenoses of small temporary water bodies was found.

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Communities of aquatic molluscs in floodplain water bodies of lowland river (Bug River, East Poland)

Jurkiewicz-Karnkowska Ewa

Polish Journal of Ecology

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2006

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Vol. 54, nr 2

253-266

EN

The present study aimed at describing composition, species richness, dominance patterns and diversity of mollusc communities aswell as frequency of individual species within selected water bodies of the valley of large Poland lowland river (lower Bug River). Suitability of molluscs in the ordination of the investigated habitats wasevaluated. The studies were carried out in the years 2003-2004 in left-bank part of the valley between 2.5-6.5 and 90-107 km of the river course in 21 water bodies heterogenous as regards size, location and successional stage. The dredge was used. 34 mollusc species were found: 23 snails and 11 bivalves. At individual sites from 2 to 15 species were noted (4 - 18 including molluscs found only as empty shells). Relatively rich malacofauna existed in larger water bodies in comparison with small stagnant and isolated ones located outside the embankment. Malacocoenoses of the investigated habitats exhibited considerable species diversity (H' = 2-3 in most habitats). Lymnaea stagnalis, Bithynia tentaculata, Planorbarius corneus and Viviparus contectus were the most frequent species (F > [or] = 50%). These species as well as moderately frequent ones constituted significant components of mollusc communities of individual water bodies. Frequencies and dominance patterns of molluscs inhabiting younger and older water bodies distinctly differed. The abundance of molluscs was mostly of the order of several to a few dozen individuals per sample (0.5-1 m2 of bottom). Principal component analysis and classification (PCCA) basing on the occurrence of molluscs expressed as the classes of abundance enabled to distinguish 4 groups of water bodies, amongwhich 2 were more distinct. The comparison of malacofauna on these two groups exhibited significant difference in frequencies. Species (S) and percentage (Psc) similarities among malacocoenosesof the investigated water bodies were generally weak or moderate, which presumably results from isolation among majority of them. More cases of high values of similarity indices were found within the gropu of small and shallow water bodies in comparison with larger and deeper ones. This may result mainly from higher habitat homogeneity at later stages or hydrarch succession. Generally higher species than percentage similarity was observed indicating the differences in dominance relations among sites with similar composition of malaconfauna.