Valuable Secondary Habitats or Hazardous Ecological Traps? Environmental Risk Assessment of Minor and Trace Elements in Fly Ash Deposits across the Czech Republic

Deposits of coal combustion wastes, especially fly ash, are sources of environmental and health risks in industrial regions. Recently, fly ash deposits have been reported as habitat surrogates for some threatened arthropods in Central Europe. However, the potential environmental risks of fly ash have not yet been assessed in the region. We analysed concentrations of 19 minor and trace elements in 19 lignite combustion waste deposits in the Czech Republic. We assessed their environmental risks by comparison with the national and EU legislation limits, and with several commonly used indices. Over 50% of the samples exceeded the Czech national limits for As, Cu, V, or Zn, whilst only V exceeded the EU limits. For some studied elements, the high-risk indices were detected in several localities. Nevertheless, the measured water characteristics, the long-term presence of fly ash, previous leaching by acid rains, and the low amount of organic matter altogether can infer low biological availability of these elements. We presume the revealed high concentrations of some heavy metals at some studied sites can be harmful for some colonising species. Nevertheless, more ecotoxicological research on particular species is needed for final decision on their conservation potential for terrestrial and freshwater biota.info:eu-repo/semantics/publishedVersio

Bioaccumulation of chemical elements at post-industrial freshwater sites varies predictably between habitats, elements and taxa: A power law approach

Elevated environmental levels of elements originating from anthropogenic activities threaten natural communities and public health, as these elements can persist and bioaccumulate in the environment. However, their environmental risks and bioaccumulation patterns are often habitat-, species- and element-specific. We studied the bioaccumulation patterns of 11 elements in seven freshwater taxa in post-mining habitats in the Czech Republic, ranging from less polluted mining ponds to highly polluted fly ash lagoons. We found nonlinear, power-law relationships between the environmental and tissue concentrations of the elements, which may explain differences in bioaccumulation factors (BAF) reported in the literature. Tissue concentrations were driven by the environmental concentrations in non-essential elements (Al, As, Co, Cr, Ni, Pb and V), but this dependence was limited in essential elements (Cu, Mn, Se and Zn). Tissue concentrations of most elements were also more closely related to substrate than to water concentrations. Bioaccumulation was habitat specific in eight elements: stronger in mining ponds for Al and Pb, and stronger in fly ash lagoons for As, Cu, Mn, Pb, Se, V and Zn, although the differences were often minor. Bioaccumulation of some elements further increased in mineral-rich localities. Proximity to substrate, rather than trophic level, drove increased bioaccumulation levels across taxa. This highlights the importance of substrate as a pollutant reservoir in standing freshwaters and suggests that benthic taxa, such as molluscs (e.g., Physella) and other macroinvertebrates (e.g., Nepa), constitute good bioindicators. Despite the higher environmental risks in fly ash lagoons than in mining ponds, the observed ability of freshwater biota to sustain pollution supports the conservation potential of post-industrial sites. The power law approach used here to quantify and disentangle the effects of various bioaccumulation drivers may be helpful in additional contexts, increasing our ability to predict the effects of other contaminants and environmental hazards on biota.info:eu-repo/semantics/publishedVersio

Sediment oxygen demand in Jordan reservoir

Sediment oxygen demand was described in Jordan reservoir during the year. Sediment from the inflow part of the reservoir had SOD20 value was lower comparing to the ones from the dam part. By the peak of summer season the dam part sediments have consumed the oxygen three times faster that the infow sediments. The influence of freshly settled seston was shown. Remove of the upper most layer of the sediment – fresh seston – caused the decrease of 47% of the SOD value the dam part sediments. Sediment oxygen demand differed both among localities and during the year in dependence on temperature

Methodology for assessing ecological potential of heavily modified and artificial water bodies

Methodology for the assessment of the ecological potential of heavily modified and artificial water bodies was developed, including water body typology. The selection of indicator metrics was based on statistical analyses of the sensitivity of each of the indicators towards the most significant stressor – eutrophication. According to these results, biological communities and their indicators were selected to comply with the requirements set forth in the Water Framework Directive (2000/60/EC)

Analysis and design of the use of variants of Cloud Business Intelligence solutions in enterprises

The diploma thesis focuses on Cloud Business Intelligence, specifically on analysis of approaches used in businesses.The aim of the diploma thesis is to analyse the possibilities of using Cloud Business Intelligence as a visualization tool compared to the full-stack Cloud Business Intelligence variant including the design of sample solutions. The thesis also suggests recommendations for companies in the transition to Cloud Business Intelligence. To achieve this goal, the author uses professional literature and qualitative research for developing drafts.First, the use of Cloud solutions in enterprises is introduced, then the author analyses the reasons and possibilities of adoption of Cloud solutions by customers. Subsequently, the author analyses the current standard and Cloud BI. Then, the author analyses and compares the variants full-stack cloud BI and Cloud BI as a visualization tool. Next, the author evaluates the given variants, including author designs of sample solutions using SAP Analytics Cloud and SAP Cloud Platform. Subsequently, the author suggests recommendations for businesses when shifting to Cloud BI. Suggestions are consulted and validated by Cloud BI experts.The work should ease the overall view of Cloud BI in businesses and help professionals and enterprises select and create a suitable Cloud BI solution.Diplomová práce se zaměřuje na oblast Cloud Business Intelligence, konkrétně na analýzu přístupů používaných v podnicích.Cílem diplomové práce je analyzovat možnosti využití Cloud Business Intelligence jako vizualizačního nástroje oproti full-stack Cloud Business Intelligence variantě včetně návrhu vzorových řešení. V práci jsou rovněž navržena doporučení pro firmy při přechodu na Cloud Business Intelligence. Pro dosažení cíle autor využívá odborné literatury a při tvorbě návrhů rovněž kvalitativního výzkumu.Nejprve je představeno využití Cloud řešení v podnicích, dále autor analyzuje důvody a možnosti adopce Cloud řešení zákazníky. Autor následně analyzuje standardní a Cloud BI současnosti. Poté autor analyzuje a srovnává varianty full-stack Cloud BI a Cloud BI jako vizualizačního nástroje. V další části práce autor zhodnocuje dané varianty včetně autorských návrhů a vzorových řešení s využitím platformy SAP Analytics Cloud a SAP Cloud Platform. Následně autor navrhuje doporučení pro podniky při přecházení na Cloud BI. Návrhy jsou konzultovány a validovány odborníky v oblasti Cloud BI. Práce by měla ulehčit celkový pohled na Cloud BI v podnicích a pomoci odborníkům a firmám při výběru a vytváření vhodného Cloud BI řešení

Evaluation of sediment importance for phosphorus internal load

Eutrophication still belongs to the serious problems waiting for solution. Phosphorus is the nutrient most often limiting the primary producers. It is well known, the improvement of water quality can be, after successful decrease of external P load, retarded by P-release from sediments. It is also necessary to realize, that the decrease of external P-load to the demanding level cannot be due to technical, political or economical reasons always possible. Measures increasing P-retention in sediments are often employed in such conditions. Many cases are known when the level of the water quality improvement remained far behind the expectations. Technical problems, still unknown mechanisms or insufficient screening followed by inadequate solution might be the reasons for the failures. The aim of this paper is to show simple decision-support system for exclusion of improper solutions and increase of the effectiveness of activities made before the rehabilitation measures realization

Phosphorus release from sediments - a comparison of methods

Phosphorus release rates from sediments were compared at two localities of Jordan Reservoir (Czech Republic) during the year. The release rates measured by incubation method were an order of magnitude higher comparing to the release rates calculated from phosphorus gradient in pore-water. A rapid decomposition of freshly settled seston at the sediment surface or just above the sediment was suggested to explain the differences

Possibilities to decrease of the phosphorus concentrations in wateshed and reservoir

P concentrations in the outflow from the watershed result from the group of factors including geology, climate, vegetation cover, morphology of streams and others. Selection of the watershed restoration strategy and its optimalisation depends on the regional, but the common idea for management of both watershed and reservoir should be the recovery to natural processes of nutrient retention together with the idea of sustainable development of the landscape. For the reservoirs, it is always lucrative to precede their overloading by phosphorus. Thinking about the decrease of P in the reservoir, the only possibility is to remove the sediments as the final deposition pool in the P-cycle. In case of the decrease of P in the water column, i.e. available for algae, another procedures of reservoir management can be used