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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

水利開發與清代嘉南平原的發展 / Irrigation Progress and the Development of Chianan Plain in Ching Dynasty

陳鴻圖, Chen, Hung Tu Unknown Date (has links)
水利開發被稱為台灣農業史上第一次革命,由於水利開發後對台灣農村經濟及農村社會產生莫大的改變。過去對於台灣農村社會的研究稍嫌薄弱,故本文從水利開發的角度切入來探討農村社會,時間以整個清代為斷限;研究區域以嘉南平原為對象。本文的研究除緒論及結論外,全文共分為四章作細部分析:第二章〈嘉南平原的自然環境及土地拓墾〉,水利開發的先決條件取決在自然環境的良窳,其次必須配合農業的發展。嘉南平原為典型的看天田,故在進入水利開發之前,必須先了解嘉南平原的自然環境。第三章〈清代嘉南平原的水利開發〉,本章主要是藉由水利開發史實的探討,來建構清代嘉南平原農村的水利原貌。本章主要分水利開發的進展、水利開發的模式及水利組織的經營三部分來說明。第四章〈水利開發對嘉南平原的影響〉,農村社會的主軸主要包括農業生產、商業行為及宗教活動三部分,而水利開發之後直接影響到農業生產、稻米產量增加、生產方式的改變、新市場圈的產生等;對農村經濟有莫大的影響,間接的影響新的地緣組織產生、水利糾紛及解決、人群關係的重新組合變了農村社會的秩序;這些影響無形中促成聚落的發展與人口的形成。第五章〈水利開發、區域發展與官府角色〉,本章主要藉由與台灣北部及閩粵的比較,來探討水利開發與區域展的關係,及不同地區官府所扮演的角色是否相同。最後從日據時期嘉南平原水利開發的轉變來釐清所謂官府角色問題。
252

Modellgestützte Analyse der Einflüsse von Veränderungen der Waldwirtschaft und des Klimas auf den Wasserhaushalt grundwasserabhängiger Landschaftselemente / Model-based Analysis of the Impact of Changing Climate and Forest Cultivation on the Water Balance of Groundwater-Dependent Landscape Elements

Natkhin, Marco January 2010 (has links)
In den letzten drei Jahrzehnten wurden in einigen Seen und Feuchtgebieten in bewaldeten Einzugsgebieten Nordost-Brandenburgs sinkende Wasserstände beobachtet. In diesen Gebieten bestimmt die Grundwasserneubildung im Einzugsgebiet maßgeblich das Wasserdargebot der Seen und Feuchtgebiete, die deshalb hier als grundwasserabhängige Landschaftselemente bezeichnet werden. Somit weisen die sinkenden Wasserstände auf einen Rückgang der wegen des geringen Niederschlagsdargebotes ohnehin schon geringen Grundwasserneubildung hin. Die Höhe der Grundwasserneubildung ist neben den hydroklimatischen Randbedingungen auch von der Landnutzung abhängig. Veränderungen in der Waldvegetation und der hydroklimatischen Randbedingungen bewirken Änderungen der Grundwasserneubildung und beeinflussen somit auch den Wasserhaushalt der Seen und Feuchtgebiete. Aktuell wird die Waldvegetation durch Kiefernmonokulturen dominiert, mit im Vergleich zu anderen Baumarten höherer Evapotranspiration. Entwicklungen in der Forstwirtschaft streben die Verringerung von Kiefernmonokulturen an. Diese sollen langfristig auf geeigneten Standorten durch Laubmischwälder ersetzt werden. Dadurch lassen sich eine geringere Evapotranspiration und damit eine höhere Grundwasserneubildung erreichen. In der vorliegenden Arbeit werden am Beispiel des Redernswalder Sees und des Briesensees die Ursachen der beobachteten sinkenden Wasserstände analysiert. Ihre Wasserstände nahmen in den letzten 25 Jahren um mehr als 3 Meter ab. Weiterhin wird untersucht, wie die erwarteten Klimaänderungen und Veränderungen in der Waldbewirtschaftung die zukünftige Grundwasserneubildung und den Wasserhaushalt von Seen beeinflussen können. Die Entwicklung der Grundwasserneubildung im Untersuchungsgebiet wurde mit dem Wasserhaushaltsmodell WaSiM-ETH simuliert. Die Analyse der Wechselwirkungen der Seen mit dem regionalen quartären Grundwasserleitersystem erfolgte mit dem 3D-Grundwassermodell FEFLOW. Mögliche zukünftige Veränderungen der Grundwasserneubildung und der Seewasserstände durch Klimaänderungen und Waldumbau wurden mit Szenarienrechnungen bis zum Jahr 2100 analysiert. Die modellgestützte Analyse zeigte, dass die beobachteten abnehmenden Wasserstände zu etwa gleichen Anteilen durch Veränderungen der hydroklimatischen Randbedingungen sowie durch Veränderungen in der Waldvegetation und damit abnehmenden Grundwasserneubildungsraten zu erklären sind. Die zukünftigen Entwicklungen der Grundwasserneubildung und der Wasserstände sind geprägt von sich ändernden hydroklimatischen Randbedingungen und einem sukzessiven Wandel der Kiefernbestände zu Laubwäldern. Der Waldumbau hat positive Wirkungen auf die Grundwasserneubildung und damit auf die Wasserstände. Damit können die Einflüsse des eingesetzten REMO-A1B-Klimaszenarios zum Ende des Modellzeitraumes durch den Waldumbau nicht kompensiert werden, das Sinken des Wasserstandes wird jedoch wesentlich reduziert. Bei dem moderateren REMO-B1-Klimaszenario werden die Wasserstände des Jahres 2008 durch den Waldumbau bis zum Jahr 2100 überschritten. / Declining water levels have been observed in some lakes and wetlands in forested catchments in North-East Brandenburg (Germany). Groundwater recharge mainly controls the supply of water available for lakes and wetlands, therefore determining them as groundwater-dependent landscape elements. Thus, the declining water levels indicate a reduction of groundwater recharge. Aspects such as climate change and different forest management practices have been considered as main factors affecting the regional groundwater regime. Currently, forest landscapes in North-East Brandenburg are dominated by pine monoculture. Depending on the climate conditions, groundwater recharge can be significantly lower under pine than under broad-leaved species like beech or oak. Regional forest administration is currently planning to expand the share of broad-leaved trees among mixed deciduous forest in the future. For this study, two lakes were chosen, the Redernswalder See and the Briesensee at Poratz. Water gauge measurements over the last 25 years showed a decline in lake water level by more than 3 m. To identify and quantify the share of changes in both, climate and forest management, the principal processes were evaluated using field measurements and water balance modelling. In the following step, alternative climate change and forestry scenarios were analysed to discover their impacts on the regional distribution of groundwater recharge. At first, the causes of the declining observed water levels were analysed. For this purpose, the physically based and fully distributed water balance model WaSiM-ETH was used to simulate groundwater recharge in the catchment and evaporation from the lake surfaces from 1958 to 2007. To analyse the geohydrological conditions, a FEFLOW 3D groundwater model was built up for the underlying Quaternary aquifer system. Possible development directions of the water balance were simulated under the influence of climate change and forest conversion until 2100. The model based analysis showed that the observed declining water levels are caused by both changes in climatic boundary conditions and in forest vegetation (age distribution and understorey) followed by decreasing groundwater recharge with an equal magnitude. The future developments of groundwater recharge and water levels are governed by changes in climatic boundary conditions and a transition from pine monoculture to broad-leaved trees. Forest conversion will show a positive effect on groundwater recharge and likely increase the water levels of lakes and wetlands. The forest conversation can not completely compensate the impact of climate change to the lake water levels, but the decrease can be significantly limited.
253

Studies On The Combustion And Gasification Of Concentrated Distillery Effluent

Patel, Nikhil 10 1900 (has links)
The need for effective disposal of huge volumes of industrial waste is becoming more challenging due to expected imposition of stringent pollution control regulations in the near future. Thermochemical conversion, particularly gasification of organics in the waste is considered the best route from the perspective of volume reduction and prevalent eco-friendly concept of waste-to-energy transformation. It is considered imperative to have adequate understanding of basic combustion features as a part of the thermochemical conversion process, leading to gasification. The aim of this thesis is to understand the fundamental combustion processes associated with one of the top listed hazardous wastes from distilleries (Biochemical Oxygen Demand (BOD) ~ 40,000 - 50,000 mg/L), commonly known as vinasse, stillage or spent wash, through experiments and modeling efforts. Specially designed experiments on distillery effluent combustion and gasification are conducted in laboratory scale reactors. As an essential starting point of the studies on ignition and combustion of distillery effluent containing solids consisting of 62 ± 2 % organics and 38 ± 2 % inorganics (primarily sugarcane derivatives), the roles of solids concentration, drop size and ambient temperature were investigated through experiments on (1) liquid droplets of 65 % and 77 % solids (remaining water) and (2) spheres of dried effluent (100 % solids) of size 0.5 mm to 20 mm diameter combusted at ambient temperatures of 773 to 1273 K. The investigation reveals that the droplets burn with two distinct regimes of combustion, flaming and char glowing. The ignition delay ‘t1’ of the droplets increased with size as is in the case of non-volatile droplets, while that of bone-dry spheres was found to be independent of size. The ‘t1’ decreased with increase in solids concentration. The ignition delay has showed an Arrhenius dependence on temperature. The initial ignition of the droplets and the dry spheres led to either homogeneous (flaming) or heterogeneous (flameless) combustion, depending on the ambient temperature in the case of sphere and on solid concentration and the ambient temperature, in the case of liquid droplets. The weight loss during the flaming combustion was found to be 50 - 80 % while during the char glowing it was 10-20 % depending on the ambient temperature. The flaming time tc is observed as tc~ d2c , as in the case of liquid fuel droplets and wood spheres. The char glowing time tc' is observed as tc ~ d2c as in the case of wood char, though the inert content of effluent char is as large as 50 % compared to 2 - 3 % in wood char. In the case of initial flameless combustion, the char combustion rate is observed to be lower. The heterogeneous char combustion in quiescent air in controlled temperature conditions has been studied and modeled using one-dimensional, spherico-symmetric conservation equations and the model predicts most of the features of char combustion satisfactorily. The measured surface and core temperatures during char glowing typically are in the range of 200 to 400 K and are higher than the controlled temperature of the furnace. Based on the results of single droplet combustion studies, combustion experiments were conducted in a laboratory scale vertical reactor (throughput ranging from 4 to 10 g/s) with the primary aim of obtaining sustained combustion. Spray of effluents with 50 % and 60 % solids (calorific value 6.8 - 8.2 MJ/kg), achieved by an air blast atomizer, was injected into a hot oxidizing environment to determine the parameters (ambient temperature and air-fuel ratio) at which auto-ignition could occur and subsequently studies were continued to investigate pre-ignition, ignition and combustion processes. Effluent with lower solids concentration was considered first from the point of view of the less expensive evaporator required in the field conditions for concentration and a spin-off in terms of better atomization consequently. Three classes of experiments were conducted: 1) Effluent injection from the wall with no auxiliary heat input, 2) Effluent injection with auxiliary heat input and 3) effluent injection within kerosene enveloping flame. Though individual particles in the spray periphery were found to combust, sustained spray combustion was not achieved in any of the three sets of experiments even with fine atomization. While conducting the third class of experiments in an inclined metallic reactor, sustained combustion of the pool resulting of accumulated spray seemed to result in large conversion of carbon. This led to the adoption of a new concept for effluent combustion in which the residence time is controlled by varying reactor inclination and the regenerative heat transfer from the product gases supplies heat for endothermic pre-ignition process occurring on the bed. Combustion and gasification experiments were conducted in an inclined plate reactor with rectangular cross section (80 mm x 160 mm) and 3000 mm long. A support flame was found necessary in the injection zone in addition to the regenerative heat transfer. Effluent with 60% solids was injected as film on the reactor bed. This film disintegrated into fine particles due to induced aerodynamic stretching and shear stripping. Combustion of individual particles provided exothermic heat profile and resulted into high carbon conversion. However, effluent clogging in the cold injection zone hindered system from attaining steady state. Effluent injected directly on the hot zone caused it to remain mobile due to the spheroidal evaporation and thus assuaging this problem. Improved mass distribution was achieved by displacing nozzle laterally in a cycle, actuated by a mechanism. Consistent injection led to sustained effluent combustion with resulting carbon conversion in excess of 98 %. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 14.0 %, CO = 7.0 %, H2 = 12.9 %, CH4 - 1 % H2S = 0.6 - 0.8 % and about 2 % of saturated moisture. This composition varied due to variation in temperature (± 30 K) and is attributed to combined effect of local flow variations, shifting zones of endothermic processes due to flowing of evaporating effluent over a large area. In order to minimize this problem, experiments were conducted by injecting effluent at higher solids (73 % solids is found injectable). The effluent was found to combust close to the injection location-due to the reduced ignition delay and lower endothermic evaporation load helped raising the local temperature. This caused the pyrolysis to occur in this hottest zone of the reactor with higher heating rates resulting in larger yield of devolatilized products and improved char conversion. Effluent combustion was found to sustain temperature in the reactor under sub-stoichiometric conditions without support of auxiliary heat input and achieved high carbon conversion. These results inspired the use of higher concentration effluent, which is also known in the case of wood to have improved gasification efficiency due to reduction in moisture fraction. In addition, the recent studies on the sulfur emission in the case of black liquor combustion in recovery boilers have revealed that with increase in solids concentration, release of sulfur in gas phase is reduces. The required concentration can be carried out using low-grade waste heat from the reactor itself. It was found through experiments that, even though spray ignition occurred at this concentration, the confined reactor space prevented the spray from attaining sustained combustion. This led to the conduct of experiments in a new vertical reactor with adequate thermal inertia, essential to prevent variations in local temperature to reach a steady state gasification and required space to accommodate the spray. The results of the experiments conducted in the vertical reactor in which effluents with 73 % solids, heated close to the boiling point and injected as fine spray in a top-down firing mode are consolidated and reported in the thesis in detail. Single particle combustion with enveloping faint flame was seen unlike stable flame found in coal water slurry spray combustion. Sustained gasification of gas-entrained particles occurred at reactor temperature in the range of 950 K - 1000 K and sub-stoichiometric air ratio 03 - 0.35 without the support of auxiliary fuel. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 10.0 -11.5 %, CO - 10.0 - 12.0 %, H2 - 6.7 - 8.0 %, CH4 = 1.75 % H2S = 0.2 - 0.4 % and about 2 % of saturated moisture. The carbon conversion obtained was in the range of 95 - 96 %. These experiments have provided the conditions for gasification. The extraction of potassium salts (mostly sulfates, carbonate and chloride) from the ash, using a simple water leaching process, was found to recover these chemicals to as high an extent as 70 - 75 % of total ash. In summary it is concluded that increasing the solid concentrations to as high levels as acceptable to the system (~ 75 %) and introducing as a fine spray of heated material (~ 363 K) into furnace with air at sub-stoichiometric conditions in a counter current combustion reactor will provide the frame work for the design of a gasification system for vinasse and similar effluent material. The thesis consists of seven chapters. Chapter 1 introduces the problem and motivation of the work presented in the thesis. Literature review is presented in Chapter 2. The Chapter 3 deals with the single particle combustion studies. The results of effluent spray combustion experiments conducted in a laboratory scale vertical reactor are presented in Chapter 4. The results of combustion and gasification experiments conducted in another variant of a reactor, namely, inclined flat plate rectangular reactor is consolidated in Chapter 5. The results of gas-entrained spray gasification experiment of higher concentration effluent injected as spray in the vertical reactor are presented in Chapter 6. The general conclusions and scope for the future work are presented in the concluding chapter 7.
254

Sensory evaluation and quality assessment of an alternative inner coating film in yogurt cartons

Arding, Fredrik January 2015 (has links)
The dairy food industry is continuously striving towards products with higher quality and longer shelf-life available to the customer at low prices. Arla Foods in Linköping, Sweden, is currently investigating the possibilities of changing the material in yogurt packaging containers by replacing the currently used carton with a different and cheaper alternative. A successful switch will give the company an economical advantage without affecting the sensory attributes (smell, taste, sight, and consistency), aroma profile or other important trademarks of the yogurt. This study is designed to examine and compare yogurt that has been stored in different packaging cartons, one coated with a single-layered low-density polyethylene (LDPE) and one coated with a currently used multi-layered ethylene-vinyl alcohol (EVOH). The study was based on the analysis and measurement of sensory attributes performed by experts, physical properties in laboratory and chemical composition in GC-FID/MS together with a discriminative test where a group of people would identify any difference between the yogurts. Together, these analyses would provide an explanation about any differences between the packaging materials by connecting physical, chemical and/or sensory characteristics. The collected results would give a better and more comprehensive picture than each analysis would do separately. The results from the study show that there is a difference between yogurts stored in LDPE-based containers and yogurts stored in EVOH-based containers and that the product was chemically affected, mainly by the level of oxygen in contact with the food. The overall assessment is that the largest difference was discovered in the taste.
255

Begriplig EU-svenska? : Klarspråksarbetets förutsättningar inom den interinstitutionella översättningsprocessen / Plain EU Swedish? : Conditions for plain language work within the inter-institutional translation process

Bendegard, Saga January 2014 (has links)
This thesis is a study of the inter-institutional translation process through which the Swedish versions of EU legislative acts are created, focusing on the conditions for plain language work within this process. These Swedish translations have long been considered incomprehensible. Complicated originals and strong demands for close correspondence to the source text have been considered the main reason. This study aims to examine the translation process, to see how institutional factors shape the scope for plain language work. The theoretical and methodological bases of the study are the sociology of translation, focusing on translation as a social activity, and ethnography, focusing on the participants’ perspective. The data analysed consist of field notes, interviews, video recordings of participants translating, and revised translations. A key factor for plain language is shown to be the demands for close correspondence to previous texts – not only the source text but also previous Swedish translations. Close correspondence is necessary due to special demands on legal translation but is also supported by other institutional factors, such as translators’ insecurity regarding legal language, short deadlines and the needs of internal readers. The use of CAT tools such as TWB further reinforces this dependence on previous texts. Other institutional factors that stand out are the relative isolation of the translation units, with limited feedback from outside the unit, and the position of the translated documents within the EU legal system. The results indicate that the difficulties for a Swedish reader are often not due to linguistic or textual formulation of the documents, but to the gap this EU position creates, between the reader’s (Swedish) and the text’s (EU) frame of reference respectively. Support for plain language is strong at the units, but the concept appears to have been partially given a local meaning, showing that the traditional understanding of plain language may not be fully applicable in this setting. This shows the necessity to identify the aspects most central to comprehensibility, for different types of texts and in different settings – a necessity not only for plain language work within the EU, but in national settings as well. / I avhandlingen studeras den interinstitutionella översättningsprocessen, till svenska, för EU:s rättsakter, med fokus på hur villkoren för klarspråksarbetet ser ut inom denna process. De svenska översättningarna har länge ansetts svårbegripliga. Svårt skrivna original och starka krav på nära överensstämmelse med källtexten har pekats ut som huvudsakliga skäl till detta. Undersökningen syftar till att ta reda på hur institutionella faktorer formar utrymmet för klarspråksarbete inom översättningsprocessen. De teoretiska och metodiska utgångspunkterna för undersökningen är översättningssociologi, som betraktar översättning som en social aktivitet, och etnografi, som betonar deltagarperspektivet. Materialet består av fältanteckningar, intervjuer, videofilmade observationer av översättnings­arbete samt granskade översättningar. Krav på nära överensstämmelse med tidigare texter visar sig vara centralt för klarspråksarbetet; inte bara överensstämmelse med källtexten utan också med tidigare svenska översättningar. Den nära överensstämmelsen är nödvändig till följd av de särskilda krav som ställs på juridisk översättning, men stöds också av andra institutionella faktorer, exempelvis översättarnas osäkerhet omkring juridiskt språk, korta tidsfrister och interna läsares behov. Användandet av CAT-verktyg som TWB förstärker ytterligare denna bundenhet till tidigare texter. Andra institutionella faktorer är enheternas relativa isolering, med begränsad återkoppling utifrån, och den position som de översatta dokumenten har inom EU:s juridiska system. Resultaten pekar på att svårigheterna för en svensk läsare ofta inte är kopplade till texternas språkliga eller textuella utformning, utan till det avstånd som skapas mellan läsarens (svenska) och textens (EU-) referensram, till följd av just textens position inom EU-systemet. Stödet för klarspråk är starkt på enheterna, men begreppet förefaller ha getts en delvis lokal innebörd, vilket visar att den traditionella innebörden av klarspråk kanske inte är helt tillämpbar i det studerade sammanhanget. Detta visar behovet av att identifiera de aspekter som är mest centrala för begripligheten, för skilda sorters texter och i skilda kontexter – en nödvändighet inte enbart för klarspråksarbetet inom EU, utan även i nationella sammanhang.
256

Spatio-Temporal Analyses of Cenozoic Normal Faulting, Graben Basin Sedimentation, and Volcanism around the Snake River Plain, SE Idaho and SW Montana

Davarpanah, Armita 10 May 2014 (has links)
This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley's K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Trajectories of the LDMs for the cross faults around each caldera define asymmetric sub-parabolic patterns similar to the reported parabolic distribution of the epicenters, and indicate sub-elliptical extension about each caldera that may mark the shape of hotspot’s thermal doming that formed each generation of cross faults. The decrease in the spatial density of the CFs as a function of distance from the axis of the track of the hotspot (SRP) also suggests the role of the hotspot for the formation of the cross faults. The parallelism of the trend of the exposures of the graben filling Sixmile Creek Formation with the LDM of their bounding cross faults indicates that the grabens were filled during or after the CF event. The global and local Moran’s I analyses of Neogene lava in each caldera along the SRP reveal a higher spatial autocorrelation and clustering of rhyolitic lava than the coeval basaltic lava in the same caldera. The alignment of the major axis of the standard deviational ellipses of lavas with the trend of the eastern SRP, and the successive spatial overlap of older lavas by progressively younger mafic lava, indicate the migration of the centers of eruption as the hotspot moved to the northeast.
257

Freshwater cyanoprokaryota blooms in the Swan Coastal Plain wetlands: ecology, taxonomy and toxicology

Kemp, Annabeth S. January 2009 (has links)
Relatively little published information on cyanoprokaryote (blue-green algal) blooms in the freshwater wetlands in Western Australia is available. There has been little research on the urban lakes and rivers, examining the relationship between environmental conditions and toxin-producing blooms. In this project the ecology, morphology and toxicity of cyanoprokaryota blooms in 27 metropolitan lakes and sumplands, as well as three major rivers, from 2000 to 2003, on the Swan Coastal Plain (SCP) in the southwest of Western Australia were investigated. / A total of 24 species were identified and described, of which nine species had not been previously documented in the area. This included the potentially toxic species Cylindrospermopsis raciborskii, Aphanizomenon ovalisporum and Anabaena bergii var. limnetica. An illustrated guide to the common bloom-forming species was generated using conventional taxonomic criteria. / Microcystis flos-aquae and Microcystis aeruginosa were the dominant bloom-forming cyanoprokaryotes, widespread in their distribution. Anabaena circinalis, A. bergii var. limnetica and Anabaenopsis elenkinii were the common filamentous species. Anabaena circinalis was common to certain freshwater sites, while A. bergii var. limnetica and A. elenkinii occurred in salinity ranging from fresh (< 1ppt) to hyposaline (3-10 ppt). Sites with similar species assemblages were identified using two-way indicator species analysis and clustering analysis. From this, a distinct distribution pattern emerged, which was defined by the main genera observed in the lakes – Microcystis, Anabaena, Aphanizomenon and Anabaenopsis. / The spatial and temporal distribution of the common bloom-forming cyanoprokaryote species was examined in conjunction with spring-summer physico-chemical data using principal component analysis. It was found that pH, water temperature and electrical conductivity/salinity accounted for variations among the lakes, with electrical conductivity the variable explaining the greatest variation. Lakes located on the coast, or further inland at the base of the Darling Scarp, were more hyposaline to saline, and the remaining lakes were fresh. Although the SCP lakes form consanguineous groups based on geochemistry and hydrology, no similarities among them were found in terms of water quality. / The relationship between nitrogen (N) and phosphorus (P) concentrations (total and dissolved inorganic) and cyanoprokaryote community structure (N-fixing versus non-N-fixing species) was investigated in five selected lakes; Yangebup Lake, Bibra Lake, Blue Gum Lake, Tomato Lake and Emu Lake. The lakes ranged from mesotrophic to eutrophic and supported spring-summer blooms containing multiple species. Overall an inverse relationship between cyanoprokaryote abundance and total ambient nutrient concentrations at the time of the blooms was evident. No transition in dominance in the community was observed in Yangebup Lake, Emu Lake and Bibra Lake, as they were dominated by non-heterocytic species (M. aeruginosa and M. flos-aquae) throughout spring and summer. For Yangebup Lake and Bibra Lake, the abundance of non-heterocytic species decreased concomitantly with decreasing dissolved inorganic N. In contrast, heterocytic species (A. circinalis) dominated the spring community in Tomato Lake, and summer community in Blue Gum Lake, when N and P concentrations were at their highest. / The presence of microcystins in Microcystis dominated blooms was examined using high performance chromatography. A total of 32 natural bloom samples, representing 13 lakes, were analysed for microcystin variants; -LR, -RR and -YR. Twenty-eight samples proved to be toxic with the highest total microcystin concentration from 1645 to 8428.6 µg L[superscript]-1, the lowest concentrations were less than 10 µg L[superscript]-1 with some below the detection limit. Microcystis aeruginosa and M. flos-aquae were associated with these microcystin-containing blooms, although M. flos-aquae appear to be less toxic. The presence of Nodularia spumigena in the Lake Yangebup was associated with high concentrations of nodularin (1664 µg L[superscript]-1). / Employing enzyme-linked immunosorbent assay for microcystins and the brine shrimp (Artemia) bioassays allowed a greater number of lake samples to be analysed and provided a rapid assessment of toxicity. The three methods for cyanotoxin detection verified Yangebup Lake, Herdsman Lake, Hyde Park, Jackadder Lake and Emu Lake as highly toxic sites. Low toxicity was demonstrated in samples from Lake Goollelal, Lake Joondalup, Lake Claremont, Blue Gum Lake and North Lake. These results provided the first evidence of cyanotoxin producing blooms in urban lakes of the SCP. / A comparative study on cyanoprokaryota blooms in Swan River estuary, upper Canning River and upper Serpentine River found that these sites, although hyposaline to saline, contained species that were common in the freshwater lakes. Sampling the river systems showed M. aeruginosa, M. flos-aquae, A. circinalis, A. elenkinii and Planktothrix planctonica to be cosmopolitan in distribution, present in SCP wetlands of varied salinity. Similarities between the upper Canning River and lakes in environmental conditions and species assemblage were demonstrated using multivariate analyses. / Toxin analysis of bloom samples from the Swan River and upper Canning River revealed microcystin concentrations were less than that of the surrounding lakes (1.05-124.16 µg L[superscript]-1). Similarly, nodularin concentrations were higher in Yangebup Lake than the upper Serpentine River. However, the dominance of Anabaena in Canning River samples, and the highly toxic result from the Artemia bioassay suggests microcystin is not the predominant cyanotoxin in this wetland. / This study has produced an overview of the distribution and morphology of cyanotoxin-producing cyanoprokaryotes in the SCP wetlands. The data presented provide the basis for further cyanoprokaryote research in Western Australia, in particular the molecular characterisation of bloom-forming toxic species.
258

Fluvial geomorphology and late quaternary geochronology of the Gwydir fan-plain

Pietsch, Timothy J. January 2005 (has links)
Thesis (Ph.D.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references: leaf 245-266.
259

Homer, Gregory, and Bill Evans? the theory of formulaic composition in the context of jazz piano improvisation /

Smith, Gregory Eugene. January 1983 (has links)
Thesis (Ph. D.)--Harvard University, 1983. / Includes bibliographical references (leaves [351]-360). Discography: leaves 360-361.
260

Urbanização na planície de inundação do Rio Gravataí - RS

Scheren, Rudimar Schuster January 2014 (has links)
O avanço da urbanização sobre as planícies de inundação causa impactos no ciclo hidrológico, na sedimentação e nas funções hidrológicas dos rios. Na planície fluvial do rio Gravataí os eventos de urbanização contribuíram para a redução da sua área inundável. Esse avanço da urbanização está associado à obras de engenharia que funcionam como barragens, que evitam que a água ocupe a planície fluvial em períodos de cheia. O presente estudo espacializa essa redução da área inundável da planície de inundação do rio Gravataí e as alterações nela recorrentes, a partir do avanço das áreas urbanas de Alvorada, Cachoeirinha, Canoas, Gravataí e Porto Alegre, sobre a planície fluvial. Foi elaborado o mapeamento da planície de inundação do rio Gravataí a partir de mapas geomorfológicos e geológicos; e das áreas inundadas, a partir de imagens do Landsat TM 5 de 10/01/2007 e 20/09/2009, aplicando o índice NDWI - Índice de Água por Diferença Normalizada - para definir o limite de inundação atual. Os dados obtidos foram comparados com um mapa das inundações da década de 1970. Também foi mapeada a expansão dos municípios analisados, nos anos de 1975, 1984 e 2009, e analisadas: A evolução urbana sobre a planície de inundação, a redução espacial das áreas inundáveis e os limites atingidos pela inundação. Os principais resultados mostram que as áreas urbanas dos cinco municípios cresceram consideravelmente sobre a planície de inundação do rio Gravataí, enquanto os limites de inundação foram reduzidos. A área inundável recuou consideravelmente em comparação ao seu alcance natural, pois os diques construídos para conter as cheias alteraram os limites de inundação e favoreceram o crescimento urbano. Na comparação entre as áreas ocorreu uma significativa expansão urbana, enquanto que inversamente, a área inundável apresentou redução espacial. Em 1975 a área de mancha urbana era de 75 Km², já em 2009 de 183 Km². A área inundável na década de 1970 tinha 58 Km², e em 2009 33 Km². As áreas urbanas na planície de inundação ocupavam 33 Km² em 1975, e em 2009 67 Km². / The advancement of urbanization on flood plains has been cause impacts on the water cycle, sedimentation and hydrological functions of the rivers . In the fluvial plain of the river Gravataí events urbanization contributed to the reduction of its flood area. This advance of urbanization is associated with engineering works that act as dams that prevent water occupy the plain river in flood season. This study spatializes this reduction of flood area in the floodplain river Gravataí and amendments thereto applicants from the advance of urban areas Alvorada , Cachoeirinha, Canoas , Gravataí and Porto Alegre, on the river plain. Was developed mapping of the floodplain of the river Gravataí from geomorphological and geological maps , and flooded areas from Landsat TM 5 of 10/01/2007 and 20/09/2009, applying the index NDWI - Water Index Normalized Difference - to set the limit of current flood . The data obtained were compared with a map of the floods of the 1970s. Was also mapped the expansion of the cities analyzed in the years 1975, 1984 and 2009 and analyzed: The urban development on the flood plain, the spatial reduction of the flood area and the limits reached by the flood. The main results show that urban areas of five counties grew considerably over the floodplain of the river Gravataí, while the flood limits were reduced. The flood area decreased considerably compared to their natural range because the levees built to contain the flood changed the limits of flooding and favored urban growth. Comparing the areas was a significant urban expansion, while conversely, the flood area was reduced space. In 1975 the urban area was 75 square kilometers, in 2009 of 183 Km². The flooded area in the 1970s was 58 Km ² and 33 Km ² in 2009. Urban areas in the floodplain occupied 33 Km ² in 1975 , and in 2009 67 Km ².

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