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

Development of commercial law at the second half of the 19th century and at the beginning of the 20th century

Tato diplomová práce pojednává o historickém vývoji obchodního práva ve druhé polovině 19. století a v první polovině 20. století. První část je věnována počátkům a prvním zákonům, kterými byly Colbertova nařízení, Francouzský zákoník nebo směnečný řád. Zásadním obdobím vývoje obchodního práva byl jistě kapitalismus, neboť vznikly další významné předpisy ? Všeobecný obchodní zákoník a Akciový regulativ. Poslední část mé práce se zabývá vývojem práva v první polovině 20. století, kdy vznikl zákon o kartelech, jednotný směnečný řád či živnostenský zákon. Na konci tohoto období byly zrušeny Všeobecný občanský a obchodník zákoník, které nahradil občanský zákoník.This diploma work deals with historical development of commercial law in the second half of 19. century and in the first half of 20. century. The first part includes its origin and also first law, which were Colbert´s statute, French Code or Exchange system. Capitalism was fundamental period of the development of commercial law, because other significant laws were created ? General Commercial Code and Stock Regulator. The last part of my work deals with the development law in the first half of 20. century, when Cartel Law, Unified Exchange system or Trading regulations were created. At the end this period were General Commercial and Civil Code violated, which the new Civil Code replaced.Ústav veřejné správy a právaAutorka představila členům komise svou diplomovou práci s názvem "Vývoj českého obchodní ho práva ve druhé polovině 19. století a na začátku 20. století." Diplomová práce pojednává o historickém vývoji obchodního práva ve druhé polovině 19. století a v první polovině 20. století. Autorka si ve své diplomové práci kladla za cíl provést analýzu vývoje českého obchodní práva v daném období a stanovit, jak toto obchodní právo ovlivňovalo dnešní právní stav

Seasonality and weather conditions jointly drive flight activity patterns of aquatic and terrestrial chironomids

Dispersal by flight is crucial for long-term survival of organisms inhabiting dynamic environments, especially small standing waters. Surprisingly, flight activity of the most abundant macroinvertebrate group in standing freshwater habitats, the Chironomidae, has rarely been studied, leaving a gap in our understanding of the environmental drivers of their dispersal activity. The goal of this study was to investigate flight activity of adult chironomids on diel and seasonal timescales in sandpit pools in the Czech Republic. We show that aquatic and terrestrial chironomids use partly alternating time windows for their flight and partly differ in their responses to weather conditions. We also compare our results to previous studies that analysed the impact of weather conditions on flight activity of aquatic insects

Disperzní a letová aktivita pakomárů stojatých vod (Diptera: Chironomidae)

I first review the significance of dispersal for individuals and populations including the role of the most significant environmental drivers on separate phases of dispersal. Emphasis is put on aquatic insects inhabiting small standing waters. The following manuscript summarizes a quantitative study of diel and seasonal flight patterns of adult Chironomidae in the Cep II sandpit in southern Bohemia. It provides one of the first comprehensive treatments of the effect of weather conditions and seasonality on the flight activity of adult Chironomidae, phenology of most common species and differences between terrestrial and aquatic species

Development of commercial law in Czech countries until the year 1989

Bakalářská práce pojednává o historickém vývoji obchodního práva v českých zemích do roku 1989. První část je věnován počátkům a prvním zákonům, kterými byly Colbertova nařízení, Francouzský zákoník nebo směnečný řád. Zásadním obdobím vývoje obchodního práva byl jistě kapitalismus, neboť vznikly další významné předpisy - Všeobecný obchodní zákoník a Akciový regulativ. Posledním obdobím před sametovou revolucí byl socialismus, který zaznamenal nejvýraznější posun a vývoj tohoto práva. Všeobecný občanský a obchodní zákoník byly zrušeny a nahrazeny novým občanským zákoníkem. Závěr této práce porovnává hospodářské a obchodní právo.This bachelor work deals with historical development of commercial law in Czech countries until the year 1989. The first part includes its origin and also first laws, which were Colbert's statute, French code or Exchange system. Capitalism was fundamental period of the development of commercial law, because other significant laws were created during it - General commercial code and Stock regulator. Socialism was the last period before the Velvet revolution, which meant the biggest advancement and the development of this law. General commercial and Civil code were violated and replaced by the new Civil code. The end of this work compares Economic and Commercial law.Ústav veřejné správy a právaDokončená práce s úspěšnou obhajobo

Dispersal and flight activity of aquatic insects: mechanisms and consequences for community assembly.

Water insects represent the considerable part of the freshwater communities. One of the most spectacular ability of those organisms is dispersion among various localities. The understanding of the dispersion mechanisms is of the key importance for unhiding the basic ecological and evolutionary processes such as colonization or maintaining high diversity patches. The aim of this thesis is to summarize findings about the dispersion and its main drivers. The experimental part deals with the influence of environmental factors on the flying activity of the water insects

Seasonality and weather conditions jointly drive flight activity patterns of aquatic and terrestrial chironomids

Abstract Background Chironomids, a major invertebrate taxon in many standing freshwaters, rely on adult flight to reach new suitable sites, yet the impact of weather conditions on their flight activity is little understood. We investigated diel and seasonal flight activity patterns of aquatic and terrestrial chironomids in a reclaimed sandpit area and analysed how weather conditions and seasonality influenced their total abundance and species composition. Results Air temperature, relative humidity, wind speed, and air pressure significantly affected total flight activity of both groups, but not in the same way. We identified an intermediate temperature and humidity optimum for the flight activity of terrestrial chironomids, which contrasted with weaker, timescale-dependent relationships in aquatic species. Flight activity of both groups further declined with wind speed and increased with air pressure. Observed flight patterns also varied in time on both daily and seasonal scale. Flight activity of both groups peaked in the evenings after accounting for weather conditions but, surprisingly, aquatic and terrestrial chironomids used partly alternating time windows for dispersal during the season. This may be driven by different seasonal trends of key environmental variables in larval habitats and hence implies that species phenologies and conditions experienced by chironomid larvae (and probably other aquatic insects with short-lived adults) influence adult flight patterns more than weather conditions. Conclusions Our results provide detailed insights into the drivers of chironomid flight activity and highlight the methodological challenges arising from the inherent collinearity of weather characteristics and their diurnal and seasonal cycles

MOESM3 of Seasonality and weather conditions jointly drive flight activity patterns of aquatic and terrestrial chironomids

Additional file 3. Adult chironomids collected during the study (Table S5)

MOESM2 of Seasonality and weather conditions jointly drive flight activity patterns of aquatic and terrestrial chironomids

Additional file 2. Weather conditions (Figures S3 and S4 and Tables S2–S4)