published_or_final_version / Geography and Geology / Master / Master of Philosophy

<p>Denna avhandling behandlar den småskaliga rumsliga variationen av löst organiskt kol (DOC, engelsk term: dissolved organic carbon), dess koncentration, masstransport och karaktär, i bäckar inom två barrskogsbeklädda avrinningsområden (delavrinningsområden 0,01-78 km²). Provtagningen gjordes uppströms och nedströms varje bäckförgrening under sommarbasflöde. Koncentrationen av DOC varierade inom en tiopotens (4-66 mg/l), liksom flera andra kemiska parametrar. Vid riksinventeringen av vattendrag för 2000 i norra Sverige noterades en snarlik spännvidd. Enligt Naturvårdverkets bedömningsgrunder för sjöar och vattendrag återfanns alla tillståndsklasser för DOC och pH, samt mänsklig påverkansgrad till försurningen inom de två studerade områdena. Den specifika avrinningen (flöde per areaenhet) varierade kraftigt i källflödena och inverkade på deras bidrag till kemin nedströms. Vattenkemin och specifika avrinningen var stabila i delavrinningsområden större än 15 km². Det kan vara nödvändigt att provta så stora områden om generella värden för landskapet önskas, men källflödenas kemi kommer då inte att kunna karakteriseras, ehuru källflödena utgör den största delen av bäcksträckan och det akvatiska ekosystemet.</p><p>Nedströms är DOC-koncentrationen, och många andra kemiska parametrar, lika med summan av bidragen från källflödena och nedströms utspädning av inflödande vatten. Tillkommer gör processer inom bäcken och vattnets utbyte med botten/grundvatten (den hyporheiska zonen), men även DOC-förluster/transformationer vid vissa bäckförgreningar och sjöar. Ovanstående resonemang förklarade bäckvattenkemins minskande variation och vanligen lägre DOC-koncentrationer nedströms i ett landskapsperspektiv. Längs bäcksträckorna observerades ingen generell minskning av DOC-koncentration eller ändring av dess karaktär. Skillnaden i DOC-koncentration och relaterade parametrar mellan källflöden och nedströms styrdes i hög grad av vilka landskapselement (myrar, sjöar och skogsmark) som vattnet hade passerat innan det hamnade i bäckarna, samt samspelseffekter med den specifik avrinningen och platserna med DOC-förlust. Prognoser med multivariata modeller baserade på kartinformation testades men kunde inte förutsäga det rumsliga mönstret eller DOC-koncentrationen med erforderlig precision.</p><p>Lämpliga rutiner inom miljöövervakningen för att övervaka den rumsliga variationen av kemin i ytvatten saknas alltjämt. Vid planering av terrestra och akvatiska skötselåtgärder bör man beakta bäckvattnets naturliga kemiska variation.</p> / <p>This thesis quantifies the small-scale spatial variation of dissolved organic carbon (DOC) concentrations, fluxes and character in two boreal catchments (subcatchments 0.01-78 km²) using ”snapshots” of summer base flow where samples were taken upstream and downstream from every node in the stream network. An order of magnitude variation was found in DOC-concentrations, and many other chemical parameters. The range was similar to that found in all of northern Sweden by the national stream survey in 2000. According to the official assessment tools used in Sweden, the entire range of environmental status for DOC, pH and human acidification influence existed within these two study catchments. A large variability in specific discharge had a major impact on the contribution of headwaters to downstream chemistry. The water chemistry parameters were relatively stable at catchment areas greater than 15 km². Sampling at that scale may be adequate if generalised values for the landscape are desired. However the chemistry of headwaters, where much of the stream length and aquatic ecosystem is found would not be characterized.</p><p>Downstream DOC-concentrations, as well as many other chemical parameters, are the sum of headwater inputs, in combination with progressive downstream dilution by inflowing water with its own DOC-concentration and character. Superimposed upon this are in-stream and hyporheic processes, as well as discrete loci of DOC loss/transformation at lakes and stream junctions. At the landscape scale, this results in a decreased downstream variation in stream water chemistry and often, but not necessarily, lower average DOC-concentrations. Along stream reaches there was not a loss of DOC-concentration or a consistent change in character. While the importance of in-stream/hyporheic processes that consistently alter DOC-concentrations along the channel network cannot be ruled out, the differences between headwater and downstream DOC-concentrations and related parameters depend largely on the mosaic of landscape elements (mires, lakes and forest soil) contributing water to the channel network, combined with patterns of specific discharge and discrete loci of DOC loss. Assessment would be facilitated by map information that could predict spatial patterns. Multivariate models using maps, however, did not give satisfactory predictions.</p><p>Appropriate procedures for dealing with spatial variation in the environmental assessment of surface waters are not yet established. An awareness of stream water chemistry’s natural spatial variability should be considered when planning aquatic and terrestrial management.</p>

Denna avhandling behandlar den småskaliga rumsliga variationen av löst organiskt kol (DOC, engelsk term: dissolved organic carbon), dess koncentration, masstransport och karaktär, i bäckar inom två barrskogsbeklädda avrinningsområden (delavrinningsområden 0,01-78 km²). Provtagningen gjordes uppströms och nedströms varje bäckförgrening under sommarbasflöde. Koncentrationen av DOC varierade inom en tiopotens (4-66 mg/l), liksom flera andra kemiska parametrar. Vid riksinventeringen av vattendrag för 2000 i norra Sverige noterades en snarlik spännvidd. Enligt Naturvårdverkets bedömningsgrunder för sjöar och vattendrag återfanns alla tillståndsklasser för DOC och pH, samt mänsklig påverkansgrad till försurningen inom de två studerade områdena. Den specifika avrinningen (flöde per areaenhet) varierade kraftigt i källflödena och inverkade på deras bidrag till kemin nedströms. Vattenkemin och specifika avrinningen var stabila i delavrinningsområden större än 15 km². Det kan vara nödvändigt att provta så stora områden om generella värden för landskapet önskas, men källflödenas kemi kommer då inte att kunna karakteriseras, ehuru källflödena utgör den största delen av bäcksträckan och det akvatiska ekosystemet. Nedströms är DOC-koncentrationen, och många andra kemiska parametrar, lika med summan av bidragen från källflödena och nedströms utspädning av inflödande vatten. Tillkommer gör processer inom bäcken och vattnets utbyte med botten/grundvatten (den hyporheiska zonen), men även DOC-förluster/transformationer vid vissa bäckförgreningar och sjöar. Ovanstående resonemang förklarade bäckvattenkemins minskande variation och vanligen lägre DOC-koncentrationer nedströms i ett landskapsperspektiv. Längs bäcksträckorna observerades ingen generell minskning av DOC-koncentration eller ändring av dess karaktär. Skillnaden i DOC-koncentration och relaterade parametrar mellan källflöden och nedströms styrdes i hög grad av vilka landskapselement (myrar, sjöar och skogsmark) som vattnet hade passerat innan det hamnade i bäckarna, samt samspelseffekter med den specifik avrinningen och platserna med DOC-förlust. Prognoser med multivariata modeller baserade på kartinformation testades men kunde inte förutsäga det rumsliga mönstret eller DOC-koncentrationen med erforderlig precision. Lämpliga rutiner inom miljöövervakningen för att övervaka den rumsliga variationen av kemin i ytvatten saknas alltjämt. Vid planering av terrestra och akvatiska skötselåtgärder bör man beakta bäckvattnets naturliga kemiska variation. / This thesis quantifies the small-scale spatial variation of dissolved organic carbon (DOC) concentrations, fluxes and character in two boreal catchments (subcatchments 0.01-78 km²) using ”snapshots” of summer base flow where samples were taken upstream and downstream from every node in the stream network. An order of magnitude variation was found in DOC-concentrations, and many other chemical parameters. The range was similar to that found in all of northern Sweden by the national stream survey in 2000. According to the official assessment tools used in Sweden, the entire range of environmental status for DOC, pH and human acidification influence existed within these two study catchments. A large variability in specific discharge had a major impact on the contribution of headwaters to downstream chemistry. The water chemistry parameters were relatively stable at catchment areas greater than 15 km². Sampling at that scale may be adequate if generalised values for the landscape are desired. However the chemistry of headwaters, where much of the stream length and aquatic ecosystem is found would not be characterized. Downstream DOC-concentrations, as well as many other chemical parameters, are the sum of headwater inputs, in combination with progressive downstream dilution by inflowing water with its own DOC-concentration and character. Superimposed upon this are in-stream and hyporheic processes, as well as discrete loci of DOC loss/transformation at lakes and stream junctions. At the landscape scale, this results in a decreased downstream variation in stream water chemistry and often, but not necessarily, lower average DOC-concentrations. Along stream reaches there was not a loss of DOC-concentration or a consistent change in character. While the importance of in-stream/hyporheic processes that consistently alter DOC-concentrations along the channel network cannot be ruled out, the differences between headwater and downstream DOC-concentrations and related parameters depend largely on the mosaic of landscape elements (mires, lakes and forest soil) contributing water to the channel network, combined with patterns of specific discharge and discrete loci of DOC loss. Assessment would be facilitated by map information that could predict spatial patterns. Multivariate models using maps, however, did not give satisfactory predictions. Appropriate procedures for dealing with spatial variation in the environmental assessment of surface waters are not yet established. An awareness of stream water chemistry’s natural spatial variability should be considered when planning aquatic and terrestrial management.

Thesis (M.Ed. (Curriculum Studies)) -- University of Limpopo, 2022 / The aim of this research is to explore initiatives taken by teachers to improve the learning of Physical Geography in Grade12 among the schools in Mamabolo Circuit, Limpopo Province, South Africa. This research was mainly qualitative in approach. A sample of 9 of Geography educators was purposively sampled in this study. The study discovered that educators need support from the Department of Education (DoE) critically when it comes to the improvement of teaching of Geography for quality results. The researcher established that the schools are not taking Geography as a subject seriously therefore, the educators teaching Geography are not considered as specialised. Therefore, this study recommends to the DoE, schools and educators to consider Geography as a subject of significance.

Slope stability maps are useful in seismic hazard evaluation, land use and emergency planning, and geomorphological studies. Such maps were generated for Giles County, Virginia (approximately 1000 square km) by the synthesis of data sets for topographic slope, surficial deposits, geologic structure, and seismic slope response. Both graphical and digital techniques were used to generate a topographic slope map. Relevant limiting slope angles according to seismic shaking and land movement studies are <15, 15-35, and >35 degrees. These slope categories were integrated with geologic factors (presence/absence of colluvium; dip direction of bedrock) to develop a set of 12 slope stability categories tailored to the Appalachian Valley and Ridge geologic/topographic province. The techniques developed are directly applicable anywhere in the Appalachian Valley and Ridge province and can be adapted to other similar physiographic provinces. Both the slope map and the regional slope stability map can be produced graphically or digitally. The graphical method is inexpensive and fast when used to examine the detailed slope stability of a small area (7.5 minute quadrangle or less about 150 square km). The computer method but is more cost-efficient than the graphical method when studying the slope stability of larger areas. The location and type of slope movement triggered by seismic shaking, torrential rainfall, rapid snowmelt, or human activities can be estimated with the use of a regional slope stability map. Integration of the slope stability map with additional factors (such as joint pattern, seismic intensity attenuation pattern, or the local water table) results in a more detailed map for specific site studies. / M.S.

Spaceborne Synthetic Aperture Radar (SAR) sensors obtain regular and frequent radar images from which ground motion can be precisely detected using a variety of different techniques. The ability to remotely measure slope displacements over large regions has many uses and advantages, although the limitations of an increasingly common technique, Differential SAR Interferometry (D-InSAR), must be considered to avoid the misinterpretation of results. Areas of low coherence and the geometrical effects of mountainous terrain in SAR imagery are known to hinder the exploitation of D-InSAR results. A further major limitation for landslide studies is the assumption that variable rates of movement over a given distance cannot exceed a threshold value, dependent upon the SAR image pixel spacing, the radar sensor wavelength and satellite revisit frequency. This study evaluates the use of three SAR image modes from TerraSAR-X and ENVISAT satellites for monitoring slow-moving landslides in the densely vegetated Three Gorges region, China. Low coherence and episodically fast movements are shown to exceed the measureable limit for regular D-InSAR analysis even for the highest resolution, 11-day interferograms. Subsequently, sub-pixel offset time-series techniques applied to corner reflectors and natural targets are developed as a robust method of resolving time-variable displacements. Verifiable offsets are generated with the TerraSAR-X imagery and the precise movement history of landslides is obtained over a period of up to four years. The capability to derive two-dimensional movements from sub-pixel offsets is used to infer a rotational failure mechanism for the most active landslide detected, and a greater understanding of the landslide behaviour is achieved through comparisons with likely triggering factors and 2D limit equilibrium slope stability analysis.

National efforts to reduce energy dependency on fossil fuels have prompted examination of macrotidal nearshore zones around the UK for potential tidal stream resource development. Although a number of prospective tidal energy sites have been identified, the local hydrodynamics of these sites are often poorly understood. Tidal-energy developers rely on detailed characterisation of tidal energy sites prior to device field trials and installation. Although first-order appraisals may make macrotidal tidal straits appear attractive for development, detailed, site-specific hydrodynamic and bathymetric surveys are important for determining site suitability for tidal stream turbine (TST) installation. Understanding the ways in which coastal features affect tidal velocities at potential TST development sites will improve identification and analysis of physical constraints on tidal-energy development. Ramsey Sound (Pembrokeshire, Wales, UK) will soon host Wales’ first TST demonstration project. However, the local hydrodynamics of the sound have been underexamined. Ramsey Sound experiences a marked tidal asymmetry, with local bathymetric features that affect flow fields which are spatially heterogeneous in three dimensions. Using Ramsey Sound as a case study, this thesis has three objectives: (1) to examine the wake created by submerged objects through field- and laboratory-based measurements, (2) to experimentally investigate the effect of submergence on wake development and decay downstream of a conical island, and (3) to develop a TST suitability tool, which examines the effects of velocity, water depth and bed slope on power availability within a macrotidal coastal area. Laboratory experiments have shown that submergence level is an important parameter controlling wake structure and extent, and that changes in submergence level affect both the 3-D flow structure in the near wake and the 2-D far wake of islands. Analysis of physical and hydrodynamic characteristics in Ramsey Sound, including tidal velocities across the swept area of the pilot TST, vertical shear in the stream flow, estimated power output, water depth and bed slope, suggests that the spatial and temporal variability in the flow field may render much of Ramsey Sound unsuitable for tidal power extraction. Although the resource potential depends on velocity and bathymetric conditions that are fundamentally local, many prospective tidal energy sites are subject to similar physical and hydrodynamic constraints. Results of this study can help inform site selection in these complicated, highly dynamic macrotidal environments.

<p>Beaches can provide a natural barrier between the ocean and inland communities, ecosystems, and resources. These environments can move and change in response to winds, waves, and currents. When a hurricane occurs, these changes can be rather large and possibly catastrophic. The high waves and storm surge act together to erode beaches and inundate low-lying lands, putting inland communities at risk. There are thousands of buoys in the Atlantic Basin that record and update data to help predict climate conditions in the state of Florida. The data that was compiled and used into a larger data set came from two different sources. First, the hurricane data for the years 1992&ndash;2014 came from Unisys Weather site (Atlantic Basin Hurricanes data, last 40 years) and the buoy data has been available from the national buoy center. Using various statistical methods, we will analyze the probability of a storm being present, given conditions at the buoy; determine the probability of a storm being present categorically. There are four different types of sinkholes that exist in Florida and they are: Collapse Sinkholes, Solution Sinkholes, Alluvial Sinkholes, and Raveling Sinkholes. In Florida there are sinkholes that occur, because of the different soil types that are prevalent in certain areas. The data that was used in this study came from the Florida Department of Environmental Protection, Subsidence Incident Reports. The size of the data was 926 with 15 variables. We will present a statistical analysis of a sinkholes length and width relationship, determine the average size of the diameter of a sinkhole, discuss the relationship of sinkhole size depending upon their soil types, and acknowledge the best probable occurrence of when a sinkhole occurs. There will be five research chapters in this dissertation. In Chapter 2, the concept of Exploratory Factor Analysis and Non-Response Analysis will be introduced, in accordance of analyzing hurricanes. Chapter 3 will also address the topic of hurricanes that have formed from the Atlantic Basin from 1992&ndash;2014. The discussion of the probability of a storm being present (also categorically) will be addressed. In Chapter 4 a study of sinkholes in Florida will be addressed. In Chapter 5 we will continue our discussion on sinkholes in Florida, but focus on the time to event between the occurrences of the sinkholes. In the last chapter, Chapter 6, we will conclude with a future works and projects that can be created from the foundations of this dissertation. </p>

Housing is one of the key issues that normally forefront the scene when considering challenges of urbanisation and urban growth. It is a fundamental aspect of human life and a major factor in delivering healthy and attractive communities as it serves to define the life space of individuals. Increasing interest is now shown towards the study of how people think of their housing and how it affects their lives. Therefore, measuring the housing quality has become an important tool to assess the efficiency of housing provision and the extent to which people are satisfied with it. This research is about examining housing quality and exploring the set of aspects through which it influences people’s quality of life (QOL). It stems out of a general concern about the state of life in cities and the general factors that shape and outline such life. It starts from some apparent observations regarding the socio-economic transformations accompanied with urban growth and development taking place in Amman, capital of Jordan, and the alterations that are soundly reforming the profile of housing provision in the city. Such alterations are seen to be adjoined with implications and challenges that are strongly influencing the state of housing sector and the overall state of life that people are living in the city. The research aims to critically investigate housing quality and the impact it has on QOL experienced by residents in Amman. In doing so, it employs an integrated conception of housing quality that poses three types of qualities: quality of provision, quality of context and quality of dwelling, and explored the implications of each of these qualities, in order to provide an overarching understanding of the influences of housing on QOL. Such understanding implies identifying the most influential aspects within each of the three types of qualities, and interpreting the impact of these aspects on QOL, taking into consideration the impact of the socio-demographic and housing provision factors. The research adopted a mixture of quantitative and qualitative methods to collecting and analysing data in order to achieve a deep understanding of the influence of housing quality in QOL. Results revealed a variation in the extent and nature of influence posed by the different housing quality components and a disparity in the response of households towards these components attributed to the differences in the socio-demographic and housing acquiring factors. It is argued that the perception of good QOL can be strongly derived from good housing quality and the set of material, social and psychological benefits obtained from it. It is suggested that the current housing provision system in Amman is in need of a reappraisal, in order to come out with a responsive housing provision scheme that provides more flexibility, equity, diversity and capability to choose among different community groups, which can help archiving better QOL.

<p>Mountain centered glaciers have played a major role throughout the last three million years in the Scandinavian mountains. The climatic extremes, like the present warm interglacial or cold glacial maxima, are very short-lived compared to the periods of intermediate climate conditions, characterized by the persistence of mountain based glaciers and ice fields of regional size. These have persisted in the Scandinavian mountains for about 65% of the Quaternary. Mountain based glaciers thus had a profound impact on large-scale geomorphology, which is manifested in large-scale glacial landforms such as fjords, glacial lakes and U-shaped valleys in and close to the mountain range.</p><p>Through a mapping of glacial landforms in the northern Scandinavian mountain range, in particular a striking set of lateral moraines, this thesis offers new insights into Weichselian stages predating the last glacial maximum. The aerial photograph mapping and field evidence yield evidence that these lateral moraines were overridden by glacier ice subsequent to their formation. The lateral moraines were dated using terrestrial cosmogenic nuclide techniques. Although the terrestrial cosmogenic nuclide signature of the moraines is inconclusive, an early Weichselian age is tentatively suggested through correlations with other landforms and stratigraphical archives in the region. The abundance and coherent spatial pattern of the lateral moraines also allow a spatial reconstruction of this ice field. The ice field was controlled by topography and had nunataks protruding also where it was thickest close to the elevation axis of the Scandinavian mountain range. Outlet glaciers discharged into the Norwegian fjords and major valleys in Sweden.</p><p>The process by which mountain based glaciers grow into an ice sheet is a matter of debate. In this thesis, a feedback mechanism between debris on the ice surface and ice sheet growth is presented. In essence, the growth of glaciers and ice sheets may be accelerated by an abundance of debris in their ablation areas. This may occur when the debris cover on the glacier surface inhibits ablation, effectively increasing the glaciers mass balance. It is thus possible that a dirty ablation area may cause the glacier to advance further than a clean glacier under similar conditions. An ice free period of significant length allows soil production through weathering, frost shattering, and slope processes. As glaciers advance through this assemblage of sediments, significant amounts of debris end up on the surface due to both mass wastage and subglacial entrainment. Evidence that this chain of events may occur, is given by large expanses of hummocky moraine (local name Veiki moraine) in the northern Swedish lowlands. Because the Veiki moraine has been correlated with the first Weichselian advance following the Eemian, it implies a heavily debris charged ice sheet emanating from the mountain range and terminating in a stagnant fashion in the lowlands.</p>