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As many as four rivers affected by brown coal mine waters were surveyed: Noteć (Lubstów open-pit mine), Pichna (Tomisławice), Widawka (Bełchatów), and Grójecki Channel (Drzewce). Identical procedures of sampling and laboratory analyses were applied in all of them. Heavy metal concentrations, pH reaction, and conductivity in river sediments were analyzed in warm periods of 2012 and 2013 to assess the impact of mine waters on riverbed material. Data on heavy metal concentrations, pH, and conductivity of water were recorded in warm periods in 2011-13. For the Lubstów open-pit mine, closed in the year 2009, data from water samples collected in 2004-05 were used. Results showed that the impact of lignite mine waters on total heavy metals in river sediments was low in the case of the Noteć and Pichna rivers. In Grójecki Channel at the site situated 1 km below the mine waters discharge the total heavy metal concentration in the bottom substrate was significantly higher than above the mine waters discharge outlet. An opposite trend was observed in the Widawka River sediments (715 mg of heavy metals·kg-1 of dry matter), where the total heavy metal concentration in the substrate 1 km below the mine waters discharge outlet decreased by approx. 44%. This was related to low concentrations of heavy metals in the Bełchatów mine waters, amounting to 0.033 mg·L-1.
The aim of the studies carried out in the year 2000 was evaluation of Mean Trophic Rank (MTR) method for water trophy assessment in the Kujawskie Lakeland and estimation of necessary changes in list of bioindicators. During researches results from MTR were compared with Chemical Index of Trophy (CIT) created for conditions of the Kujawskie Lakeland. Obtained results were very promising and both methods could be used in this region in the future.
Wskaźniki makrofitowe, takie jak Mean Trophic Rank (MTR), Macrophyte Biological Index for Rivers (IBMR), River Macrophyte Nutrient Index (RMNI), Reference Index (RI) i inne są z powodzeniem wykorzystywane w ocenie jakości ekosystemów rzecznych. Opierają się one głównie na tolerancji poszczególnych taksonów roślin naczyniowych, mszaków, wątrobowców i makroglonów na trofię wody. Oceniany odcinek rzeki Noteć znajdujący się powyżej jeziora Gopło odbiera zrzuty wód kopalnianych z odkrywki węgla brunatnego Tomisławice. W 2012 roku przeprowadzono badania dotyczące wpływu wód kopalnianych z odkrywki węgla brunatnego na trofię wód Noteci. Wykorzystano w tym celu kilka wskaźników makrofitowych oraz przeprowadzono analizy wskaźników troficznych na wybranych stanowiskach. Dla wybranych stanowisk dysponowano także wynikami badań z 2008 roku, które wykorzystano w celach porównawczych. Na podstawie uzyskanych wyników można stwierdzić, że wpływ charakterystyki troficznej wód kopalnianych na wielkości wskaźników makrofitowych oraz wskaźników jakości wody był nieznaczny. Wynika to z małych różnic trofii wód rzecznych i wód kopalnianych oraz braku wrażliwości wykorzystanych wskaźników makrofitowych na wypadnięcie pojedynczych gatunków wskaźnikowych z grupy roślin wodnych. Rośliną, która wypadła z listy makrofitów poniżej dopływu rzeki Pichny był grążel żółty, a niektóre wykazywały znaczny spadek pokrycia bez istotnego wpływu na wartości wskaźników makrofitowych. Świadczy to o niezbyt wysokiej czułości tego typu wskaźników w sygnalizowaniu nieznacznych zmian w środowisku wodnym.
Most lakes in Poland are shallow and vulnerable to degradation mostly due to lake morphology and landscape structure. Other factors, like discharged sewage, internal loading and human activities in the watershed are also important. During studies on Brdowskie Lake, water samples were taken twice a year (spring and summer season) from the surface layer and analyses of soluble reactive phosphates, total phosphorus, nitrates, conductivity, five-day biochemical oxygen demand, chlorophyll a, dry mass of seston and Secchi depth were undertaken. Brdowskie Lake is situated in Kujawskie Lakeland and its catchment basin covers about 155.3 km2. The littoral vegetation is dominated by reed bed with a minor presence of other taxa. The lake is very susceptible to degradation (morphology, agricultural lands, housing) and has several potential sources of pollution, e.g. Noteæ River, a nameless stream and summer houses. In general, water quality of the lake was better during the spring season, especially in terms of chlorophyll a and dry mass of seston concentrations. In 1997- -2006, the level of conductivity was very changeable with the maximum values observed in 1999-2001. Significant correlations between some parameters in certain seasons of the year were found, e.g. between chlorophyll a and Secchi depth during spring and total phosphorus and phosphates in summer. The impact of water level fluctuations on water quality parameters, like total phosphorus and chlorophyll a was observed. According to the results, the quality water in Brdowskie Lake is improving. After a biological wastewater treatment plant in the catchment had opened, the rate of salts flowing into the lake with sewage was reduced.
Wyniki badań przeprowadzonych w latach 1997-2003 nad wodami jezior oraz cieków świadczą o podwyższonej trofii wód powierzchniowych Kujaw Południowych. Na okresowe obniżanie jakości wody w jeziorach, szczególnie w okresie letnim, wpływ mają niskie stany wody oraz liczne rozproszone źródła zanieczyszczeń. Wody płynące są na badanym obszarze zróżnicowane pod względem stopnia zanieczyszczenia. W ciekach odprowadzających wody z jezior stwierdzono niższe stężenia fosforu i azotu niż na pozostałych odcinkach rzecznych, co można wiązać z akumulowaniem części zanieczyszczeń przez jeziora, co zostało częściowo poparte ocena statystyczną.
Studies of the impact of river shading on biological diversity of aquatic plants were carried out in central and western parts of the Polish Lowlands. Data was collected during field surveys in 2003 to 2010. Studied rivers represented watercourses with small and average watershed areas according to the Water Framework Directive, and sand was the dominant substrate of the river bottom. To evaluate the impact of shading on aquatic plants, biodiversity metrics such as number of taxa, Shannon-Wiener index, Simpson index, and evenness index were used. For statistical analyses, pairs of studied sites were compared and it was found that increased shading was limiting biodiversity, enhancing growth of bryophytes, and had minor influence on macrophyte indices describing ecological status. In the case of most of the diversity indices, high statistical significance was observed for pairs of sites with greater differences of shading between each other.
The surveys made on 80 river sites in Ecoregion 14 (Poland) were undertaken in years 2006-2008 to determine influence of river modifications and water trophy on variability of taxonomic structure of macrophyte taxa. Field surveys were conducted using widely accepted methods such as the River Habitat Survey and Mean Trophic Rank, supplemented by physico-chemi¬cal analyses of water and hydrochemical index for evaluation of trophic level. Obtained results showed, that there are significant differences between lowland and upland river sites according to the rate of channel modifications, concentration of trophic parameters and thus between aquatic macrophyte structure. The variability of taxonomic structure of aquatic macrophytes was found according to site altitude, rate of modifications and water quality parameters. It was found, that in case of lowland rivers the simultaneous influence of modifications and water trophy can affect taxonomic structure stronger than in upland sites, where level of kinetic energy of water flow plays the most important role.
The aim of this paper is to assess usefulness of different measures when determining central tendencies which characterise the environmental requirements of living organisms. Mathematical analyses were made of the environmental parameters of river macrophyte communities which were taken as a representative pattern of different levels of biological structures. To deliver a representative dataset, botanical surveys were carried out on a range of British rivers together with environmental assessment and the plant communities groups were identified based on characteristic species according to eslished phytosociological criteria. The mean values and standard univariate medians of the revealed associations were compared with means calculated on the basis of advanced transformation and also with the rarely calculated multivariate L median. Due to high variance and asymmetrical distribution, the analyses based on the mean-value appeared to be limited in application. To avoid this disadvantage transformation to obtain normality of the dataset standardisation was proposed although even this did not fully reach a satisfactory symmetry. It was concluded that each environmental variable for each single biota must be individually treated by a suile transformation to obtain approximately normal distributions. The univariate median was very resistant to the effects of outliers but gave a flattened output of the environmental dataset making the partitioning of biological units very difficult. The multivariate L median appeared to be unaffected by outliers. It enabled to obtain considerable ordering of communities against individual environmental parameters without data transformation.
The paper presents an assessment of the effect of three water reservoirs near the Nienawiszcz village (Western Poland) on the improvement of landscape structure and stability. The reservoirs were reconstructed in the years 1999-2012 in places where ponds and post-glacial lake were present in the past. A number of works were also carried out to organise and enrich the landscape around studied area, which is a part of real estate. The research carried out in the years 2013-2015 included valorisation of the natural environment, determination of the ecological and spatial model of the landscape and assessment of landscape stability according to the criterion of the connection network. Valorisation of the natural environment has shown the dominance of areas with outstanding and high natural values (class I and II). Regenerated water reservoirs and wood plantings increased the number and diversity of landscape islands and the connections between them, which additionally improved the stability of the landscape. Water reservoirs and numerous landscape activities in this area significantly influenced the increase of biological diversity as well as the diversity and functionality of the landscape.
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