38 research outputs found
Fairtrade Label Use in Business
101 s., 22 s. příl. :obr., tab., grafy +CD ROMFairtrade, v českém překladu spravedlivý obchod, je pro českého spotřebitele relativně novinkou. Přesto, že jeho institucionální i mediální podpora neustále roste, není povědomí místních obyvatel dostatečné. Diplomová práce se ve své teoretické části snaží o osvětu a vysvětlení základních principů fairtrade včetně popisu historických skutečností vedoucích ke vzniku hnutí. Dále je popsána situace rozvojových zemí a vysvětlení neúčinnosti rozvojové pomoci ze strany rozvinutých tržních ekonomik. V neposlední řadě je definován globální potravinový problém a absolutní chudoba, která postihuje právě ty země, pro které má být hnutí fairtrade řešením jejich tíživé situace. Cílem teoretické části práce je seznámení čtenáře s touto rozvojovou problematikou a ospravedlní nutnosti fairtrade. Praktická část práce je věnována popisu podnikatelského prostředí, na který navazuje analýza dvou místních podniků z nichž jeden při svém podnikání využívá známku faitrade. Cílem praktické části práce je rozhodnutí, zejména na základě ekonomických a marketingových ukazatelů, zda je pro podnik výhodné podnikat pod záštitou fairtrade
Diatoms in cryoconite holes and adjacent proglacial freshwater sediments, Nordenskiöld glacier (Spitsbergen, High Arctic)
Cryoconite holes are small, extreme habitats, widespread in the ablation zones of gla-ciers worldwide. They can provide a suitable environment for microorganisms including bacteria, cyanobacteria, algae, fungi, and invertebrates. Diatoms have been previously recovered from cryoconite holes of Greenland and of Svalbard, and recent findings from Antarctica suggest that cryoconite holes may harbor a unique diatom flora distinct from other aquatic habitats nearby. In the present study, we characterize the diatom communi-ties of Nordenskiöld glacier cryoconite holes in Billefjorden (Svalbard, Spitsbergen), and multivariate approaches were used to compare them with three freshwater localities in the immediate vicinity to investigate possible sources of the species pool. We found cryoconite holes to have similar or greater average genus-richness than adjacent lake/ ponds habitats, even though lower numbers of valves were recovered. Overall, cryoconite hole diatom communities differed significantly from those observed in lakes, suggesting that other sources actively contribute to these communities than nearby lakes alone. This further suggests that (i) diatoms present in cryoconite might not exclusively originate from aquatic habitats, but also from (semi-) terrestrial ones; and (ii) that a much wider area than the immediate surroundings should be considered as a possible source for cryoconite diatom flora
Diatom communities differ among Antarctic moss and lichen vegetation types
Continental Antarctica is a polar desert containing sparse pockets of vegetation within ice-free areas. Despite the recognized association between lichens, mosses and epiphytic diatoms, the environmental factors controlling diatom community structure are poorly understood. We investigated the association between diatom communities and host vegetation characteristics by experimentally adding nutrients and/or water to two bryophyte (healthy and moribund) and two lichen (crustose and Usnea) vegetation types in the Windmill Islands. Diatom communities were morphologically characterized, diversity indices calculated and differences between treatments, vegetation type and vegetation characteristics tested. We identified 49 diatom taxa, 8 of which occurred with \u3e 1% relative abundance. Bryophyte and lichen vegetation harboured significantly different diatom communities, both in composition and diversity indices. Specifically, Luticola muticopsis was more prevalent in moribund bryophytes and crustose lichens, and Usnea lichens showed lower species richness than other types. While nutrient and water additions did not significantly alter diatom communities, diversity indices and some species showed relationships with vegetation physiological characteristics, notably %N and δ13C, suggesting the importance of ambient gradients in water and nutrient availability. Collectively, this work suggests that future conditions favouring the dominance of a particular vegetation type may have a homogenizing effect on the terrestrial diatom communities of East Antarctica
Luminescence Measurements of Sediment Cores from Lake Esmeralda and Monolith Lake, James Ross Island Archipelago
The James Ross Island archipelago is located at the northern end of the Antarctic Peninsula, one of the most sensitive regions to global climate changes. The islands are characterised by large deglaciated areas containing remarkable sedimentary archives, including lacustrine sediments, which record past climatic conditions. Sedimentary sequences from two lakes in the area have been retrieved for multi-proxy analyses of sediment properties to reconstruct the past climatic and environmental evolution. This data needs to be set into a reliable chronological framework to correlate the environmental records with other regional palaeoreconstructions from ice cores, marine sediments and glacial chronologies. There are large uncertainties in radiocarbon chronologies ensuing from large reservoir effects and the scarcity of terrestrial macroremains. Luminescence dating techniques, which measure ages of commonly occurring minerals, could therefore provide a robust chronology and offer new insights into the age and mode of sediment deposition. Previous studies of Antarctic lacustrine sediments have shown large residual thermoluminescence (TL) signals, and smaller residual infra-red stimulated luminescence (IRSL) signals. Optically stimulated luminescence (OSL) has been applied to samples from raised Antarctic lake deltas and shorelines, and sediments from subglacial lakes.
Sedimentary cores were collected from Lake Esmeralda (Vega Island) and Monolith Lake (James Ross Island), with one core from each lake examined in this work. Luminescence profiling has been conducted on the two cores, with measurements on bulk sediments using the SUERC Portable OSL instrument under blue and IR stimulation, and laboratory profiling using IRSL and TL on separated 90-250 µm polymineral grains and OSL on 90-250 µm quartz grains. The profile measurements show significant differences in estimated stored dose between methods, with the OSL giving the lowest doses, followed by IRSL and TL, consistent with previous studies showing large residual signals in TL and smaller residuals in some IRSL measurements. Quantitative OSL analyses were conducted on 150-250 µm quartz grains extracted from selected samples from these cores to calculate sedimentary ages.
For Lake Esmeralda, the ages show a general increase with depth, from 0.4 to 0.8 ka, with some small age inversions between 40 and 50 cm and between 140 and 150 cm.
For Monolith Lake, the top 5 cm cover an age range similar to the entire length of the Lake Esmeralda core and show significantly lower luminescence sensitivity. Below 5 cm there is a significant increase in apparent age, to 2.5-3.0 ka, which is approximately constant within ~0.5 ka for most of the core, and increased sensitivity. The lower samples below 26 cm are significantly younger and form a progression of older aged material at greater depth. This suggests that within the last 1000 years there has been a significant change in the sediment supply to Monolith Lake. The age profile for Monolith Lake, in particular the younger ages for material below 26 cm, suggests that the sediments below 5 cm carried a residual dose when they were deposited in the lake, with the deepest sediments in the core carrying a smaller residual, or even having being reset and thus giving a true age for these layers. The larger doses measured by IRSL and TL in the profiling indicate that it is likely that the luminescence centres associated with these signals carried a residual dose for all samples. Further exploration of these signals may reveal additional information on the sediment histories
Adaptations of cyanobacteria and algae to extreme conditions of polar regions
Katedra ekologieDepartment of EcologyFaculty of SciencePřírodovědecká fakult
Intercultural communication - the French vs. the Quebecers
The Master’s thesis is focused on intercultural communication between the French and the Quebecers. Intercultural communication represents communication among different cultures and it has crucial role in several areas in today’s globalized world. The aim of this thesis is to prove that there are many differences between the French and the Quebecers. Also, to identify these differences and propose possible solutions among these cultures. The aim is achieved by a qualitative reasearch, specifically structured interviews, by theoretical findings, and personal experience. The first part of the thesis is focused on the explanation of key concepts related to intercultural communication and conflicts in management. Vital terms are cultural dimensions based on theoretical concepts of two Dutch authors Geert Hofstede and Fons Trompenaars. The second part characterizes and compares the chosen cultures through application of cultural dimensions’ theories. The last part refers to the research itself and evaluation of its results. Recommendations on conflict prevention and possible solutions are proposed.Diplomová práce se zabývá interkulturní komunikací mezi Francouzi a Quebečany. Interkulturní komunikace představuje komunikaci mezi různými kulturami a v dnešním globalizovaném světě má klíčovou roli v řadě oblastí. Cílem práce je prokázat, že mezi Francouzi a Quebečany existují rozdíly, tyto rozdíly identifikovat a navrhnout možná řešení případných konfliktů mezi těmito kulturami. Cíl práce je naplněn za pomocí kvalitativního výzkumu ve formě strukturovaných rozhovorů, teoretických zjištění a vlastních zkušeností. První část práce je zaměřena na objasnění pojmů souvisejících s interkulturní komunikací a konflikty v managementu. Zásadním pojmem jsou kulturní dimenze, vycházející z teoretických prací nizozemských autorů Geerta Hofstedeho a Fonse Trompenaarse. Druhá část charakterizuje a porovnává zvolené kultury prostřednictvím aplikace těchto teorií kulturních dimenzí. Poslední část se týká samotného výzkumu, vyhodnocení jeho výsledků a následných doporučení prevence konfliktů mezi danými kulturami a možnosti jejich řešení
Taxonomy, ecology and biogeography of aquatic and limno-terrestrial diatoms (Bacillariophyta) in the Maritime Antartic Region
Diatoms (Bacillariophyta) are one of the most diverse algal groups in the Antarctic Region and play a dominant role in almost all freshwater and terrestrial ecosystems. Despite this overall occurrence, little is known about the diversity, ecology and biogeography of this group in the Maritime Antarctic Region. The main objective of this thesis is therefore to define the taxonomical, ecological and biogeographical characterisation of aquatic, semi- aquatic and moss-inhabiting diatom communities from two islands in the Maritime Antarctic Region: James Ross Island and Livingston Island, located on opposite sides of the Antarctic Peninsula. In this study, a total of 250 samples from three different habitat types (lakes, streams & seepage areas and mosses) from Byers Peninsula (Livingston Island) and Ulu Peninsula (James Ross Island) have been analysed. Using light and scanning electron microscopy, a rather diverse diatom flora composed of 178 taxa, belonging to 43 genera has been identified. Although even until recently, it was generally accepted that the Antarctic diatom flora was mostly composed of cosmopolitan taxa, several new species could be described as a new for science during this PhD study (a reflection of this work is presented in chapters 2 & 3 and in Appendices). Habitat type and..
Taxonomie, ekologie a biogeografie sladkovodních a limnoterestrických rozsivek (Bacillariophyceae) v maritimní Antarktidě
Diatoms (Bacillariophyta) are one of the most diverse algal groups in the Antarctic Region and play a dominant role in almost all freshwater and terrestrial ecosystems. Despite this overall occurrence, little is known about the diversity, ecology and biogeography of this group in the Maritime Antarctic Region. The main objective of this thesis is therefore to define the taxonomical, ecological and biogeographical characterisation of aquatic, semi- aquatic and moss-inhabiting diatom communities from two islands in the Maritime Antarctic Region: James Ross Island and Livingston Island, located on opposite sides of the Antarctic Peninsula. In this study, a total of 250 samples from three different habitat types (lakes, streams & seepage areas and mosses) from Byers Peninsula (Livingston Island) and Ulu Peninsula (James Ross Island) have been analysed. Using light and scanning electron microscopy, a rather diverse diatom flora composed of 178 taxa, belonging to 43 genera has been identified. Although even until recently, it was generally accepted that the Antarctic diatom flora was mostly composed of cosmopolitan taxa, several new species could be described as a new for science during this PhD study (a reflection of this work is presented in chapters 2 & 3 and in Appendices). Habitat type and...Rozsivky (Bacillariophyta) představuji jednu z nejrozmanitějších skupin řas v antarktické oblasti, hrající dominantní roli téměř ve všech sladkovodních a suchozemských ekosystémech. Přestože se jedná o tak důležitou skupinu, její diverzitě, ekologii a biogeografii v oblasti maritimní Antarktidy bylo věnováno jen málo pozornosti. Hlavním cílem této práce je taxonomická, ekologická a biogeografická charakteristika sladkovodních, limno-terestrických a mechy osídlujících společenstev rozsivek ze dvou ostrovů v oblasti maritimní Antarktidy: z ostrova Jamese Rosse a ostrova Livingston, které se nacházejí na opačných stranách Antarktického poloostrova. V této práci bylo analyzováno celkem 250 vzorků z různých typů habitatů (z jezer, potoků, mělkých mokřadů a mechů) poloostrova Byers na ostrově Livingston a poloostrova Ulu na ostrově Jamese Rosse. S využitím světelného a skenovacího elektronového mikroskopu byla popsána poměrně bohatá rozsivková flóra složená ze 178 druhů zastupujících 43 rodů. Ačkoli ještě donedávna bylo všeobecně uznáváno, že rozsivková flora antarktické oblasti se skládá z převážně kosmopolitních druhů, výsledky této práce a popis mnoha nových druhů (některé z nich prezentovány v kapitolách 2, 3 a Appendixech 1-5) tuto teorii vyvrací. Zdá se, že vedle vlivu fyzikálně-chemických...Department of EcologyKatedra ekologieFaculty of SciencePřírodovědecká fakult