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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.
451

A critical evaluation of the environmental law framework applicable to carbon capture and storage in South Africa / Edward Arthur Rea

Rea, Edward Arthur January 2013 (has links)
The objective of this study is to conduct a critical evaluation of the environmental law framework applicable to carbon capture and storage (hereafter CCS) in South Africa. The discussion begins by confirming that CCS has a place in environmental law as a mitigation measure. The inclusion of CCS in the clean development mechanism could incentivise the development of environmental law frameworks for CCS in South Africa. Implementation of CCS is gradual, with only eight large scale integrated CCS projects having been established around the world. An appreciation of key scientific concepts is helpful for an understanding of the CCS process. The CCS project life cycle and related impacts on the environment provide a context for discussion of the legal requirements accompanying the CCS life cycle. The Constitution of the Republic of South Africa, 1996 and the National Environmental Management Act 107 of 1998 constitute appropriate framework legislation for CCS. Decision 3/CMP.1, Modalities and procedures for a clean development mechanism as defined in Article 12 of the Kyoto Protocol adopted by the Conference of the Parties serving as the Meeting of the Parties to the Kyoto Protocol held at Montreal from 28 November to 10 December 2001 March 2006 provides international legal requirements accompanying the project life cycle against which the South African legal framework is examined. Some provisions of additional South African laws and policies will be applicable to CCS depending on the nature of the specific CCS project, but specific regulations may have to be developed for South Africa. Policy documents have been gradually bringing clarity to the way forward in arriving at a legal framework for CCS, and by reference to existing local legislation and international guidance, an environmental law framework for CCS can be developed for South Africa. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2014
452

Zero-energy infill housing: front and back house options in Manhattan Kansas

Pradhan, Trishna Rani January 1900 (has links)
Master of Science / Department of Architecture / Gary J. Coates / This thesis was undertaken to investigate and seek possible architectural solutions to two issues. Firstly, fragmentation of the American family structure into a variety of new household types presents new design challenges to architects today. The single family house, once an 'ideal family' home, now needs to be redesigned to accommodate these changing lifestyles. Secondly, global warming and threats of an impending energy crisis loom large over humankind today. Environmentally-responsive architectural design can and should address both of these burgeoning problems. A program was developed as the basis for designing new infill housing in the city of Manhattan, Kansas, a small Midwestern college town. The aim was to provide dwelling units that would accommodate a wide range of family types and use patterns of the entire life cycle while fitting in to the existing architectural fabric of the neighborhood. After a literature review, it was concluded that 'front and back house' design was the most suitable option. In this context, three types of front and back house designs are presented. These options are further divided into thirteen subtypes. It is shown that these designs fulfill the spatial needs of a variety of differing households such as houses with an office, a multigenerational home and units that permit aging in place. An independent study was undertaken to achieve a 'zero energy threshold' for one of the designs within the design matrix presented in the thesis. A 60%-65% decrease in energy usage was attained in the front house and 50% in the back house by increasing the overall efficiency of the building envelope and by utilizing energy efficient appliances. Utilization of a 2 X 6.4 kW grid-connected solar photovoltaic system provided enough energy to power the house (inclusive of front & back houses). A Geothermal heating/cooling system was employed to further decrease the use of fossil fuel. With reduced energy needs and use of a gird connected solar system it was possible to achieve a 'net-zero energy house', which is defined as a house that generates as much as or more than the total energy it uses over the course of a year. An economic analysis of the front and back house and proposed energy systems was also performed. Calculations suggest that rent from the back house could provide substantial financial benefits to the owner of the front house. Although use of non-conventional energy systems demanded a larger initial investment, studies showed that savings made on the utility bills would eventually help recover this investment within the lifetime of the systems.
453

A critical evaluation of the environmental law framework applicable to carbon capture and storage in South Africa / Edward Arthur Rea

Rea, Edward Arthur January 2013 (has links)
The objective of this study is to conduct a critical evaluation of the environmental law framework applicable to carbon capture and storage (hereafter CCS) in South Africa. The discussion begins by confirming that CCS has a place in environmental law as a mitigation measure. The inclusion of CCS in the clean development mechanism could incentivise the development of environmental law frameworks for CCS in South Africa. Implementation of CCS is gradual, with only eight large scale integrated CCS projects having been established around the world. An appreciation of key scientific concepts is helpful for an understanding of the CCS process. The CCS project life cycle and related impacts on the environment provide a context for discussion of the legal requirements accompanying the CCS life cycle. The Constitution of the Republic of South Africa, 1996 and the National Environmental Management Act 107 of 1998 constitute appropriate framework legislation for CCS. Decision 3/CMP.1, Modalities and procedures for a clean development mechanism as defined in Article 12 of the Kyoto Protocol adopted by the Conference of the Parties serving as the Meeting of the Parties to the Kyoto Protocol held at Montreal from 28 November to 10 December 2001 March 2006 provides international legal requirements accompanying the project life cycle against which the South African legal framework is examined. Some provisions of additional South African laws and policies will be applicable to CCS depending on the nature of the specific CCS project, but specific regulations may have to be developed for South Africa. Policy documents have been gradually bringing clarity to the way forward in arriving at a legal framework for CCS, and by reference to existing local legislation and international guidance, an environmental law framework for CCS can be developed for South Africa. / LLM (Environmental Law and Governance), North-West University, Potchefstroom Campus, 2014
454

Cold exposure and thermal comfort among patients in prehospital emergency care : innovation research in nursing

Aléx, Jonas January 2015 (has links)
Background Patients’ cold exposure is a neglected problem in prehospital emergency care. Cold stress increases pain and anxiety and contributes to fear and an overall sense of dissatisfaction. When left untreated, cold stress disturbs vital body functions until ultimately reaches hypothermia. Aim The overall aim was to investigate patients’ experiences of thermal comfort and reactions to cold exposure in prehospital emergency care and to evaluate the effects of an intervention using active warming from underneath. Method Study I: Persons (n=20) injured in a cold environment in the north of Sweden were interviewed. Active heat was given to 13 of them. Study II: In wintertime, 62 patients were observed during prehospital emergency care. The field study was based on observations, questions about thermal discomfort, vital signs, and temperature measurements. Study III: Healthy young persons (n=23) participated in two trials each. Data were collected inside and outside a cold chamber. In one trial, the participants were lying on a regular ambulance stretcher and in a second trial on a stretcher supplied with a heated mattress. Outcomes were the Cold Discomfort Scale (CDS), back, finger, and core body temperature, four statements from the State-TraitAnxiety-Inventory (STAI), vital signs, and short notes about their experiences of the two stretchers. Study IV: A quantitative intervention study was conducted in prehospital emergency care in the north of Sweden. The patients (n=30) in the intervention group were transported in an ambulance supplemented with a heated mattress on the stretcher, whereas only a regular stretcher was used in the ambulance for the patients (n=30) in the control group. Outcomes were the CDS, finger, core body, and air temperature, and questions about cold experiences. Results Study I: Patients suffered more because of the cold than from the pain of their injuries. The patients were in a desperate need of heat. Study II: Patients are exposed to cold stress due to cold environments. There was a significant decrease from the first measurement in finger temperature of patients who were indoors when the ambulance arrived, compared to the measurement taken in the ambulance. In the patient compartment of the ambulance, 85% of the patients had a finger temperature below the comfort zone and almost half of them experienced the patient compartment in the ambulance to be cold. The regular mattress surface temperature at the ambulance ranged from -22.3 to 8.4 ºC. Study III: A statistical increase of the participants’ back temperature was found between those lying on the heated mattress compared to those lying on the regular mattress. The heated mattress was experienced as warm, comfortable, providing security, and easy to relax on. Study IV: Thermal comfort increased for the patients in the intervention group and decreased in the control group. A significant higher proportion of the participants rated the stretcher as cold to lie on in the control group compared to the intervention group. Conclusion The ambulance milieu is too cold to provide thermal comfort. Heat supply from underneath increased comfort and might prevent cold stress and hypothermia
455

Breeding for Nitrogen Use Efficiency in Soft Red Winter Wheat

Hitz, Katlyn 01 January 2015 (has links)
Nitrogen use efficient (NUE) wheat varieties have potential to reduce input costs for growers, limit N runoff into water ways, and increase wheat adaptability to warmer environments. Previous studies have done little to explain the genetic basis for NUE and components, nitrogen uptake efficiency (NUpE) and nitrogen utilization efficiency (NUtE). Four studies were conducted to 1) determine genotypic stability of NUE under high and low N regimes and under warming 2) determine effect of warming on NUE 3) indentify QTL associated with NUE components 4) assess the utility of canopy spectral reflectance (CSR) as a high-throughput phenotyping device for NUE. Genotypic response to N stress or warming varied. Uptake efficiency was found to be more important than utilization efficiency to genotypic performance under high and low N environments and under warming. Selection under low N for NUpE and under high N for NUtE most efficiently identified NUE varieties. Uptake and utilization were lower under warming due to quickened development. No strong correlations between the CSR indices and NUE existed. No QTL were found to be significantly associated with NUE components. Further research into the mechanisms controlling NUE and to reveal plant response to N stress and under warming is necessary.
456

Effects of warming and nutrient enrichment on feeding behavior, population stability and persistence of consumers and their resources

Uszko, Wojciech January 2016 (has links)
Consumer-resource interactions are the basic building blocks of every food web. In spite of being a central research theme of longstanding interest in ecology, the mechanisms governing the stability and persistence of consumer-resource interactions are still not entirely understood. In particular, theoretical predictions on consumer-resource stability along gradients of temperature and nutrient enrichment diverge widely and are sometimes in conflict with empirical results. In this thesis I address these issues from the angle of the functional response, which describes a consumer’s feeding rate as a function of resource density. Specifically, I explore mechanistic, nutrient-based consumer-resource interaction models with respect to the influence of feeding behavior (the shape of the functional response), environmental temperature, nutrient enrichment, and resource quality on consumer-resource stability and persistence. In order to parameterize these models I performed extensive laboratory experiments with pairs of freshwater pelagic algae and grazers of the genus Daphnia, which are widespread, ecologically important model organisms. I found a sigmoidal type III functional response in every studied Daphnia-algae species pair. The exact form of its shape is described by an exponent b which is determined by fitting functional response models to the experimental data. A high value of b can stabilize consumer-resource systems under the otherwise destabilizing influence of nutrient enrichment, as predicted by a novel stability criterion relating b to the consumer’s prey handling time, food conversion efficiency and mortality. Estimated parameter values and, consequently, stability predictions are sensitive to the method of parameter estimation, and I propose a new estimation procedure that minimizes parameter uncertainty. Because many consumers’ feeding rates depend on temperature, warming is expected to strongly affect food web stability. In functional response experiments over a broad temperature gradient, I found that the attack rate coefficient and the maximum ingestion rate of Daphnia are hump-shaped functions of temperature. Moreover, the functional response exponent increases with warming towards stronger type III responses. Plugging these findings into a nutrient-based consumer-resource model, I found that predator persistence is a U-shaped function of temperature in nutrient enrichment-temperature space. Enrichment easily turns the system unstable when the consumer has a type II response, whereas a type III response opens up a large region of stability at intermediate, for the consumer optimal, temperatures. These findings reconcile seemingly conflicting results of earlier studies of temperature effects on consumer-resource dynamics, which can be mapped as special cases onto the enrichment-temperature space. I finally demonstrate the utility of three key model ingredients - temperature dependence of rate parameters, a mechanistic description of the dynamics of algal resources, and a type III functional response in Daphnia - by successfully implementing them in the description and explanation of phytoplankton-Daphnia dynamics in a mesocosm experiment exploring effects of warming on the spring succession of the plankton.
457

Recent climate change over the Arabian Peninsula : trends and mechanisms

AlSarmi, Said Hamed Mohammed January 2014 (has links)
The global climate is changing. Compared with many parts of the world, especially North America and Europe, relatively little is known about how climate has changed over the Arabian Peninsula (AP) in recent decades. Quantifying the climate change in the mean and extreme temperature and precipitation variables and understanding the mechanisms behind these changes are essential for establishing adequate and proper adaptation strategies to ensure sustainability, reduce vulnerability and safeguard livelihoods. Four papers in this thesis contribute to that objective, utilising a combination of in situ high quality meteorological station data and high resolution regional climate model data. The first paper quantifies the trends in monthly, seasonal and annual mean, maximum, minimum temperatures and Diurnal Temperature Range (DTR) variables and total precipitation. The station dataseries are tested for quality control and homogeneity. A non-parametric test is used to calculate the trends and evaluate the trend significance for individual stations, subregions (Non-monsoonal and Monsoonal) and for the whole area average. There is a high significant increase in the temperature variables especially the minimum temperature (during 1980-2008 and over all the AP the trend of annual minimum temperature is 0.55 °C decade<sup>-1</sup> while the annual maximum temperature trend is 0.32 °C decade<sup>-1</sup>) which leads to significant decrease in the DTR. The precipitation is decline but insignificantly. The non-monsoonal region located north of 20° N has experienced higher rates of warming than the monsoonal region. Spring and summer seasons witness the highest significant warming. The interannual variability of the AP temperature and precipitation shows marked negative association after 1998. The second paper utilises the AP daily data of maximum temperature, minimum temperature and precipitation to calculate climate extremes indices, evaluate the regional/subregional trends of these indices and assess the trend significance. There is a clear significant decrease of cold temperature extremes and a significant increase in the warm temperature extremes. The increase in the nighttime temperature extremes is remarkable in the last two decades (the rate of increase of the warm night frequency is 3.6&percnt; decade<sup>-1</sup> during 1986-2008). The spatial trend patterns reveal a latitudinal distinction whereby the northern AP experiences an increase associated with day-time extremes while for the night-time extremes the trends are higher and significant for the southern region. Precipitation indices trends are weak and although they show general decrease in the last two decades they are insignificant. The changes in the Dew Point (Td) and the Mean Sea Level Pressure (MSLP) indicate possible changes in the regional dynamics. The third paper uses the Providing Regional Climates for Impact Studies (PRECIS) regional climate model forced by the European Centre for ERA-Interim re-analysis (ERA-Interim) to simulate the AP climate during 1990-2008. PRECIS simulation is validated based on climate mean and trends. The model simulation captures the mean climatic conditions and patterns, the increasing temperature tendency, as well as the decreasing precipitation observed in the last two decades. However, PRECIS has cold bias especially with the minimum temperature and it overestimates the precipitation over the high lands or regions close to them over the southwestern mountains and underestimates the precipitation over the southeastern mountains. The model products provide indications on the reasons behind the highest daytime spring warming (decrease of specific humidity) and significant nighttime summer warming (increase of Sea Surface Temperature (SST)). The model fails to simulate the recent increase of the nighttime temperature parameters over AP. The final paper addresses the possible local atmospheric circulations, SST and remote modes of variability associated with the recent AP climate extreme changes. Using the PRECIS simulation, composite difference maps for some surface, upper atmospheric circulation maps and SSTs between two period 1990-1997 and 1998-2008 have been calculated. The composite difference maps reveal significant local changes in these atmospheric and oceanic variables which possibly partly explain the recent regional warming and drying conditions during the last two decades. In addition, relationships of the regional/subregional extremes indices timeseries have been calculated with some known remote modes of variability. There is a clear, strong relation of El Niño Southern Oscillation (ENSO) with the AP climate in all the seasons except in winter. The North Atlantic Caspian Sea Pattern (NCP) influences the regional climate in winter especially the temperature variables.
458

Mosses as mediators of climate change : implications for tree seedling establishment in the tundra

Lett, Signe January 2017 (has links)
Alpine and arctic tree line expansion depends on the establishment of tree seedlings above the current tree line, which is expected to occur with climate warming. However, tree lines often fail to respond to higher temperatures. Other environmental factors are therefore likely important for tree seedling establishment. Above the tree line, establishing seedlings encounter existing vegetation such as bryophytes, which often dominate in arctic and alpine tundra. Bryophytes modify their environment in various ways and may mediate climate change effects on establishing tree seedlings, and with that tree line expansion. The aim of this thesis was to understand if and how the environment, in particular bryophytes, mediates the impact of climate change on tree seedling establishment at the alpine and arctic tree line. This was explored by reviewing literature on tree seedling establishment at alpine and arctic tree lines globally. In addition, tree seedling survival and growth of Betula pubescens and Pinus sylvestris were assessed experimentally. Here, individuals were planted into mono-specific mats of different bryophytes species and exposed to warming and different precipitation regimes. The literature review revealed that besides from temperature, tree seedling establishment is affected by a wide range of abiotic and biotic factors including water, snow, nutrients, light, disturbance and surrounding vegetation. Furthermore the review revealed that for example vegetation can change tree seedling responses to climate change. The experiments showed that especially tree seedling survival was adversely affected by the presence of bryophytes and that the impacts of bryophytes were larger than those of the climate treatments. Seedling growth, on the other hand, was not hampered by the presence of bryophytes, which is in line with earlier findings that seedling survival, growth and seed germination do not respond similarly to changes in environmental conditions. Moreover, we found several indications that vegetation above the tree line, including bryophytes, mediated tree seedling responses to warming and precipitation or snow cover. This thesis shows that temperature alone should not be used to predict future tree seedling establishment above the alpine and arctic tree line and that extrapolations from climate envelope models could strongly over or under estimate tree line responses to warming. This underlines the value of multi-factorial studies for understanding the interplay between warming and other environmental factors and their effects on tree seedling establishment across current tree lines.
459

The imapct of drought and climate warming on Central European broad-leaved mixed forests

Zimmermann, Jorma 09 September 2015 (has links)
No description available.
460

Mosses as mediators of climate change : implications for tree seedling establishment in the tundra

Lett, Signe January 2017 (has links)
Alpine and arctic tree line expansion depends on the establishment of tree seedlings above the current tree line, which is expected to occur with climate warming. However, tree lines often fail to respond to higher temperatures. Other environmental factors are therefore likely important for tree seedling establishment. Above the tree line, establishing seedlings encounter existing vegetation such as bryophytes, which often dominate in arctic and alpine tundra. Bryophytes modify their environment in various ways and may mediate climate change effects on establishing tree seedlings, and with that tree line expansion. The aim of this thesis was to understand if and how the environment, in particular bryophytes, mediates the impact of climate change on tree seedling establishment at the alpine and arctic tree line. This was explored by reviewing literature on tree seedling establishment at alpine and arctic tree lines globally. In addition, tree seedling survival and growth of Betula pubescens and Pinus sylvestris were assessed experimentally. Here, individuals were planted into mono-specific mats of different bryophytes species and exposed to warming and different precipitation regimes. The literature review revealed that besides from temperature, tree seedling establishment is affected by a wide range of abiotic and biotic factors including water, snow, nutrients, light, disturbance and surrounding vegetation. Furthermore the review revealed that for example vegetation can change tree seedling responses to climate change. The experiments showed that especially tree seedling survival was adversely affected by the presence of bryophytes and that the impacts of bryophytes were larger than those of the climate treatments. Seedling growth, on the other hand, was not hampered by the presence of bryophytes, which is in line with earlier findings that seedling survival, growth and seed germination do not respond similarly to changes in environmental conditions. Moreover, we found several indications that vegetation above the tree line, including bryophytes, mediated tree seedling responses to warming and precipitation or snow cover. This thesis shows that temperature alone should not be used to predict future tree seedling establishment above the alpine and arctic tree line and that extrapolations from climate envelope models could strongly over or under estimate tree line responses to warming. This underlines the value of multi-factorial studies for understanding the interplay between warming and other environmental factors and their effects on tree seedling establishment across current tree lines.

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