Siga este enlace para ver otros tipos de publicaciones sobre el tema: Environmental aspects of Coast changes.
Tesis sobre el tema "Environmental aspects of Coast changes"
Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros
Consulte los 50 mejores tesis para su investigación sobre el tema "Environmental aspects of Coast changes".
Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.
También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.
Explore tesis sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.
1
Fehrenbacher, Fairlight Marie. "Predicting shoreline change due to nearshore dredging at Folly Island, South Carolina". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/21527.
Texto completo
2
Knapp, Jarred Lee. "The effects of ocean acidification and temperature change on the West Coast rock lobster (Jasus lalandii)". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97802.
Texto completoResumen
Thesis (PhD)--Stellenbosch University, 2015.ENGLISH ABSTRACT: The West Coast rock lobster (WCRL), Jasus lalandii, is a critical marine fisheries resource for South Africa and may in future be negatively affected by the changes in seawater parameters associated with the ongoing anthropogenic carbon dioxide (CO2) emissions. These CO2 emissions have been linked to a global decrease in ocean pH (termed “ocean acidification”) and an increase in temperature. There are strong estimates that these changes are to worsen in coming centuries. This warranted research because of 1) the low current level of the resource (2.6% of pristine) and 2) the relatively unexplored physiological- and other biological responses of the WCRL to environmental stressors. This information is essential for the sustainable management of the resource by government scientists in times of global- and regional climate change. In the short term, it was found that the WCRL was able to rapidly and reversibly respond to acute changes in seawater pH (pH 7.4), this was achieved primarily through the active up-regulation of bicarbonate levels in the haemolymph. Maintaining extracellular pH protects oxygen transport mechanisms, which are sensitive to pH changes due to the large Bohr effect that this study also revealed, in the respiratory protein, haemocyanin of adult WCRL. The energy cost of actively maintaining extracellular pH, however, is expected to affect growth and potentially survival in the long term. This was tested on juvenile WCRL that were exposed to a reduced seawater pH of 7.3 (18.8 °C) over a period of 28 weeks. Results revealed that survival was not influenced and acid-base regulation in the hypercapnia-exposed lobsters was maintained throughout the duration of the trial, however, this led to a reduced growth rate. Subsequently, in order to replicate field conditions more closely, a combination of effects, namely seawater pCO2 (pH 8 and 7.3) and different temperatures (15.6 and 19 °C) on the growth of juvenile WCRL were assessed over an exposure period of 48 weeks in a second chronic trial. In contrast to the initial trial (28 weeks), where hypercapnia was assessed separately, lobsters exposed to hypercapnia had a higher growth rate than those at the same temperature exposed to a “natural” (normocapnic) seawater pH. The difference was interpreted as an indication that food availability/quality may negatively affect stress response, as feeding in the first trial was later considered “sub-optimal” in comparison to that of the second trial. In the latter, although both hypercapnia and temperature affected growth rates, temperature was the largest contributor to differences observed between treatments. The order of growth rates for lobsters from different treatments was: hypercapnia/high temperature > normocapnia/high temperature > hypercapnia/low temperature > normocapnia/low temperature. In this trial too, irrespective of treatment, lobsters were able to maintain extracellular pH within a relatively narrow range over the extent of the trial and survival was not negatively affected by hypercapnia or high temperature. In order to compare the sensitivity of juvenile WCRL to that of adults, with regards to the effect of changes in extracellular pH on oxygen transport, and to assess the impact of chronic hypercapnia, haemocyanin from juveniles was studied in detail after the first growth trial. This revealed that juvenile WCRL have a similar Bohr effect to that of adults. In addition, the haemocyanin of hypercapnia-exposed juveniles showed an increased affinity to oxygen caused by an intrinsic change in its molecular structure. This was interpreted as an energy-saving mechanism, because at the same time, haemocyanin concentration in these animals was lower than in normocapnic lobsters. At the termination of the second chronic trial, the immunological response to the combined stressors was assessed, namely total circulating haemocyte counts (THC) and the ability to clear/inactivate an introduced dose of a bacterium, Vibrio anguillarum. A pilot experiment on non-treated juveniles revealed a similar resting THC to that of other lobster species, and culturable V. anguillarum was rapidly cleared from their haemolymph. The effect of chronic exposure to a combination of effects, namely hypercapnia and different temperatures, was subsequently tested after termination of the second chronic trial. There were no differences between treatments in a) baseline THC (i.e. before bacterial challenge) and 2) the capability to clear culturable bacteria from haemolymph. The only difference was the circulating THCs post-bacterial challenge, as they were reduced in the hypercapnic-, high temperature treatment, compared with all other treatments. The reason is unknown, but it is speculated that it may have been linked to an increased metabolic demand in these lobsters. Overall, these results demonstrate the great plasticity of the WCRL at the molecular-, biochemical and physiological level. They provide important initial information for government fisheries scientists to aid in predicting future development of, and potential threats to the WCRL resource, as well as providing a platform from which the direction of future studies can be determined.
AFRIKAANSE OPSOMMING: Die Weskus-seekreef, Jasus lalandii, is ’n belangrike seevisseryhulpbron vir Suid-Afrika en kan in die toekoms negatief geraak word deur die veranderinge in seewaterparameters wat met voortgesette antropogeniese vrystellings van koolstofdioksied (CO2) verband hou. Hierdie CO2-vrystellings word met ’n wêreldwye daling in die pH van seewater (oftewel “oseaanversuring”) en ’n temperatuurstyging verbind. Alles dui daarop dat hierdie veranderinge in die volgende eeue sal vererger. Dít regverdig navorsing weens 1) die huidige skaarste aan dié hulpbron (2,6% van oorspronklike getalle), en 2) die betreklik onverkende fisiologiese en ander biologiese reaksies van die kreef op omgewingstressors. Hierdie inligting is noodsaaklik om staatswetenskaplikes in staat te stel om die hulpbron te midde van wêreldwye en streeksklimaatsverandering volhoubaar te bestuur. Op kort termyn word daar bevind dat die Weskus-kreef vinnig en omkeerbaar op akute veranderinge in die pH van seewater reageer (pH 7,4). Dít is hoofsaaklik deur die aktiewe opwaartse regulering van bikarbonaatvlakke in die hemolimf vasgestel. Die handhawing van ekstrasellulêre pH beskerm die meganismes wat suurstof vervoer, wat gevoelig is vir pH-veranderinge weens die beduidende Bohr-effek in die respiratoriese proteïen, hemosianien, by die volwasse kreef – nóg ’n bevinding van hierdie studie. Tog sal die energiekoste verbonde aan die handhawing van ekstrasellulêre pH na verwagting groei en moontlik ook oorlewing op lang termyn beïnvloed. Dít is getoets op jong Weskus-krewe wat oor ’n tydperk van 28 weke aan seewater met ’n verlaagde pH van 7,3 (18,8 °C) blootgestel is. Resultate dui daarop dat oorlewing nié geraak word nie, en dat suur-basis-regulering in die hiperkapnie-blootgestelde krewe vir die volle duur van die proef gehandhaaf is, hoewel dit tot ’n verlaagde groeitempo gelei het. Ten einde natuurlike omstandighede akkurater na te boots, is ’n kombinasie van uitwerkings, naamlik pCO2 van seewater (pH 8 en 7,3) en verskillende temperature (15,6 en 19 °C), op die groei van jong krewe oor ’n blootstellingstydperk van 48 weke in ’n tweede chroniese proefneming beoordeel. In teenstelling met die aanvanklike proef (28 weke), is hiperkapnie afsonderlik beoordeel en het krewe wat aan hiperkapnie blootgestel is ’n hoër groeitempo getoon as dié by dieselfde temperatuur wat aan seewater met ’n ‘natuurlike’ (normokapniese) pH blootgestel is. Dié verskil is vertolk as ’n aanwyser dat voedselbeskikbaarheid/-gehalte ’n negatiewe uitwerking op stresreaksie kan hê, aangesien voeding in die eerste proefneming later as ‘suboptimaal’ beskou is vergeleke met dié van die tweede proef. In die tweede proef, hoewel hiperkapnie én temperatuur groeitempo’s beïnvloed het, was temperatuur die grootste bydraer tot die verskille wat tussen behandelings opgemerk is. Die orde van die kreefgroeitempo’s met die verskillende behandelings was: hiperkapnie/hoë temperatuur > normokapnie/hoë temperatuur > hiperkapnie/lae temperatuur > normokapnie/lae temperatuur. In die tweede proef kon die kreef ook, ongeag behandeling, ekstrasellulêre pH vir die volle duur van die proefneming binne ’n betreklik beperkte bestek handhaaf, en het nóg hiperkapnie nóg hoë temperatuur ’n negatiewe invloed op oorlewing gehad. Om die gevoeligheid van jong Weskus-krewe met dié van volwasse krewe te vergelyk wat betref die uitwerking van veranderinge in ekstrasellulêre pH op suurstofvervoer, en om die impak van chroniese hiperkapnie te bepaal, is die hemosianien van jong krewe deeglik ná die eerste groeiproef bestudeer. Dít het aan die lig gebring dat die jong kreef ’n soortgelyke Bohr-effek as volwassenes toon. Daarbenewens toon die hemosianien van hiperkapnie-blootgestelde jong krewe ’n verhoogde affiniteit tot suurstof, wat deur ’n intrinsieke verandering in molekulêre struktuur veroorsaak word. Dít is as ’n energiebesparingsmeganisme vertolk, aangesien hemosianienkonsentrasie by hierdie diere terselfdertyd laer was as by normokapniese kreef. Aan die einde van die tweede chroniese proefneming is die immunologiese reaksie op die gekombineerde stressors beoordeel, naamlik totale sirkulerende hemosiettellings (THC) en die vermoë om ’n toegediende dosis van die bakterie Vibrio anguillarum op te ruim/te deaktiveer. ’n Toetseksperiment met niebehandelde jong krewe dui op ’n soortgelyke rustende THC as dié van ander kreefspesies, en kweekbare V. anguillarum is vinnig uit die hemolimf opgeruim. Die effek van chroniese blootstelling aan ’n kombinasie van faktore, naamlik hiperkapnie en verskillende temperature, is vervolgens na afloop van die tweede chroniese proef getoets. Die verskillende behandelings lewer dieselfde a) THC op die basislyn (met ander woorde voor toediening van die bakterie), en 2) opruimingsvermoë van kweekbare bakterieë uit die hemolimf op. Die enigste verskil was die THC’s ná toediening van die bakterie, wat laer was met die hiperkapniese hoëtemperatuurbehandeling as met alle ander behandelings. Die rede hiervoor is onbekend, maar hou vermoedelik verband met ’n verhoogde metaboliese vereiste by hierdie krewe. Oor die algemeen toon hierdie resultate die beduidende plastisiteit van die Weskus-seekreef op molekulêre, biochemiese en fisiologiese vlak. Dit bied belangrike aanvanklike inligting vir staatsvisserywetenskaplikes om die toekomstige ontwikkeling van én moontlike bedreigings vir die kreefhulpbron te voorspel, en voorsien boonop ’n platform van waar die rigting van toekomstige studies bepaal kan word.
3
Johnson, Charley R. "Migration of Dredged Material Mounds: Predictions Based on Field Measurements of Waves, Currents, and Suspended Sediments, Brunswick, GA". Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-04082005-145658/unrestricted/johnson%5Fcharley%5Fr%5F200505%5Fmast.pdf.
Texto completoResumen
Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2005.F. Michael Saunders, Ph.D., Committee Member ; Kevin Haas, Ph.D., Committee Member ; Paul A. Work, Ph.D., Committee Chair. Includes bibliographical references.
4
Rennie, Alistair Flett. "The role of sediment supply and sea-level changes on a submerging coast past changes and future management implications /". Thesis, Connect to e-thesis, 2006. http://theses.gla.ac.uk/843/.
Texto completoResumen
Thesis (Ph.D.) - University of Glasgow, 2006.Ph.D. thesis submitted to the Department of Geographical and Earth Sciences, University of Glasgow, 2006. Includes bibliographical references. Print version also available.
5
de, la Vega Leinert Anne Cristina. "Flandrian coastal environmental changes : evidence from three sites in Mainland Orkney, Scotland". Thesis, Coventry University, 1998. http://curve.coventry.ac.uk/open/items/8e4ae838-181f-4a9d-9b99-48fd40dff69f/1.
Texto completoResumen
The Orcadian coastline is characterised by a high energy paraglacial environment, where remobilisation of abundant glacigenic sediment has favoured the building of numerous barriers. To date, there has been little work on either patterns of relative sea-level change or coastal processes affecting Orkney during the Flandrian. The present research provides an understanding of Flandrian coastal environmental changes in three areas of Mainland Orkney. Detailed morphological, lithostratigraphical and biostratigraphical work was undertaken and has revealed distinctive back-barrier sequences which illustrate the diversity of coastal responses to complex interactions between relative sea-level trends, sediment supply and coastal configuration. Scapa Bay provides direct evidence of relative sea-level rise and coastal retreat during the early Flandrian. There, a freshwater marsh was flooded by the sea c.8.5 kyrs BP at c.-5.4 m 0.0. Abundant sediment supply from nearby drift cliffs was remobilised inland by wave refraction before c.7 kyrs BP, and led to the formation and rapid progradation of swash-aligned barriers (SAB) across the valley mouth. By c.6.6 kyrs BP, direct marine influence was restricted in the back-barrier area, although saltmarshes persisted until c.5 kyrs BP. The enclosed lagoon was then progressively infilled by terrestrial sediments and a freshwater marsh was formed. The multiple barrier complex at Scapa Bay demonstrates land progradation against the backdrop of long-term rising relative sea level. This was facilitated by continuous sediment supply in a sheltered embayment. At the Bay of Carness, a single SAB was built during the early Flandrian. Between c.6.5 and 5.4 kyrs BP, marine influence was at its highest and a saltmarsh formed between c.-3.2 and -2.57 m 0.0. No direct marine flooding has, however, been recorded at the site. Later, a brackish lagoon occupied the coastal depression indicating a rising water table. This lagoon was gradually infilled by terrestrial sediments as soil erosion occurred in the the catchment. Slow inland migration of the SAB during the late Flandrian has been related to complex barrier and lagoon interactions in a context of sediment starvation. The sheltered setting of the site enabled the barrier to keep cohesiveness throughout its inland translocation. However, its present morphology shows clear signs of instability. The Bay of Skaill is the most exposed and dynamic coastal environment of the sites investigated. Abundant sand supply led to the building of a dune ridge during the middle Flandrian and to the pending of a freshwater loch in the back-dune area. By c.6.1 kyrs BP, aeolian processes became dominant and the dune ridge progressively migrated landward, while machair developed inland. After c.4.4 kyrs BP, the bay was gradually formed as the dune ridge retreated to its present position. Moreover, a SAB developed and eroded the seaward dune edge. At present, the SAB is migrating rapidly inland due to sediment starvation and exposure to storm activity. The Flandrian vegetational history around the three sites was also investigated. This accorded with that already established for the islands. Herbaceous vegetation was initially dominant, although a Betula-Corylus woodland, including Salix, Alnus and possibly Quercus, developed during the early Flandrian. This reached its maximum extent c.5 kyrs BP. Anthropogenic impact from Neolithic onwards is believed to have significantly affected the landscape studied, primarily via woodland clearance and mixed farming practices. Between c.4 and 2.5 kyrs BP, a combination of natural and anthropogenic factors led to the spreading of heathland and to a possible decline of anthropogenic activities.
6
Wang, Yaoping. "Statistical Downscaling along the US Eastern Coast by Two Methods with Application on Intensity-Duration-Frequency curve Changes". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417824178.
Texto completo
7
Greenwood, Karin C. "Sea surface temperatures around the souhtern [i.e. southern] African coast : climatological aspects and applications". Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53583.
Texto completoResumen
Thesis (MSc)--Stellenbosch University, 2003.ENGLISH ABSTRACT: The oceanic and meteorological systems that characterize the southern African coastline are well-documented. In this thesis, these characteristics have been considered in conjunction with the analysis of a unique set of sea surface temperature (SST) data, obtained from measuring sites around the southern African coast, to determine the variability of SSTs in the immediate coastal region of southern Africa, and to demonstrate how this variability impacts on marinerelated economic activities. As part of the analysis process, various statistical techniques have been applied to the data over different time periods to establish the extent of the spatial variability of SSTs along the southern African coastline. From the results it has been possible to identify three distinctly different 'climatological' regions around the southern African coast; viz a cooler west coast region with a low annual and seasonal SST variability and a higher variability from day-ta-day, a warmer east coast region with a higher annual and seasonal SST variability and a lower variability from day-ta-day; and a temperate south coast region with a highly erratic annual, seasonal and day-ta-day SST variability. Furthermore, it has been possible to identify, albeit small, the existence of a high and a low frequency signal of 12-15 days and 40-60 days, respectively, in the three different regions. There is also evidence of the periodic occurrence of anomalously warm and cold SST events in all three regions, and a probability of <1.1% of a day-ta-day SST anomaly of >3°C (+3°C or- 3°C) occurring anywhere along the southern African coastline. The general causes of SST change have been discussed within the context of the heat budget equation. Furthermore, the effects of the variability of SST on the climate and marine life around southern Africa and the resulting impact on the various marine-related economic activities (such as aquaculture, air-sea rescue and power stations) have been identified, and shown to be both positive and negative.Finally, it should be noted, that economic infonnation relating to marine activities is closely guarded due to inter-industry competition. It has therefore been difficult to quantify the exact impact of the effects of SST variability on these activities.
AFRIKAANSE OPSOMMING: Die oseaniese en weerkundige stelsels wat die kuslyn van suidelike Afrika kenmerk is goed gedokumenteer. Die stelselkenmerke is in hierdie verhandeling ondersoek aan die hand van 'n unieke datastel van seeoppervlaktemperature (SST) afkomstig van meetplekke aan die kus van suidelike Afrika, ten einde die veranderlikheid van SST in die onmiddelike kusomgewing van suidelike Afrika vas te stel, asook om te demonstreer hoe hierdie veranderlikheid inwerk op seeverwante ekonomiese aktiwiteite. As deel van die proses van analise is verskeie statistiese metodes gebruik om die data oor verskeie tydperke te ontleed ten einde die omvang van ruimtelike veranderlikheid van SSTs langs die kus van suidelike Afrika te bepaal. Uit die resultate was dit moontlik om drie duidelike onderskeibare 'klimatologiese' streke aan die kus van suidelike Afrika te identifiseer; te wete 'n koeler weskusstreek met 'n lae jaarlikse en seisoenale SST-veranderlikheid en hoër dag-tot-dag veranderlikheid, 'n warmer ooskusstreek met 'n hoër jaarlikse en seisoenale SST-veranderlikheid en laer dag-tot-dag verandelikheid; asook 'n gematigde suidkusstreek met 'n hoogs wisselvallige jaarlikse, seisoenale en dag-totdag SST-veranderlikheid. Dit was verder moontlik om, alhoewel klein, die bestaan van lae en hoë frekwensie seine van 12-15 dae en 40-60 dae onderskeidelik in die drie streke te identifiseer. Daar is ook tekens van die periodieke voorkoms van anomale warm en koue SSTgebeurtenisse in al drie streke en 'n waarskynlikheid van <1.1% van die voorkoms van 'n dagtot- dag SST-anomaliteit van >3°C (+3°C of -3°G) op enige plek langs die suider Afrikaanse kuslyn. Die algemene oorsake van veranderings in SST is bespreek binne die konteks van die formule vir die behoud van hitte-energie. Die invloed van SST-veranderlikheid op die klimaat en die seelewe om suidelike Afrika en die gevolglike effek op mariene-verwante ekonomiese aktiwiteite (soos akwakultuur, lug-see-redding en kragstasies) is ook geïdentifiseer en is aangetoon om beide positief en negatief te wees Ten laaste dien dit gemeld te word dat ekonomiese inligting met betrekking tot mariene aktiwitweite goed bewaar word as gevolg van kompetisie in die bedryf. Dit was derhalwe moeilik om die presiese impak van die gevolge van SST-veranderlikheid op sodanige aktiwiteite te kwantifiseer.
8
Kent, Avidan. "International trade, investment, and climate change : a tale of legal and institutional fragmentation". Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648583.
Texto completo
9
Adey, Jonathan Max. "Aspects of the sustainability of creel fishing for Norway lobster, Nephrops norvegicus (L.), on the west coast of Scotland". Thesis, University of Glasgow, 2007. http://theses.gla.ac.uk/524/.
Texto completoResumen
This thesis describes a study of a number of aspects of the Nephrops creel fishery. Various aspects have been studied. In particular, work has focused on how the biology of Nephrops affects its catchability in creels, as well as assessing the environmental impacts of the Nephrops creel fishery. A smaller study relating to the physiological effects of the capture and transport of live creel-caught Nephrops, has also been undertaken. Fishery-directed sampling of Nephrops displayed strong seasonal trends in catch composition and catch rate, reflecting patterns in the Nephrops moult and reproductive cycles. Most females were caught in the early spring, following moulting and mating, with catch rates becoming low after spawning in autumn. Catches of males were greatest around February following moulting. Of those animals caught, males were larger than females. These seasonal patterns reflect the exploitation of different components of the stock throughout the year. Fishery sampling also showed there to be considerable stock heterogeneity both among and within creel fisheries. Global positioning system (GPS)-linked data loggers fitted to selected fishing boats provided a more detailed assessment of spatial variability in catch rate. Results showed both effort and landings per unit effort (LPUE) to be patchily distributed in the area studied, further illustrating considerable stock heterogeneity throughout the area. Both approaches illustrated that catch rate varied with sediment type, with high catch rates of small animals on sandy to firm mud and high catch rates of large animals on softer mud. Additionally, population modelling indicated that, in the areas studied, Nephrops are not currently being growth overfished. Behavioural observations in both the field and laboratory indicated a low probability of entry to creels by approaching Nephrops, particularly if other crustacean species were inside the creel. Larger Nephrops appeared to have a greater threshold for disturbances such as and the presence of conspecifics or other species as well as reduced gear avoidance, suggesting that Nephrops creels select larger animals in the population. Using sea pens as an indicator of physical disturbance of the sea bed showed that impacts from creeling were low. The sea pens Virgularia mirabilis and Pennatula phosphorea were caught in moderate quantities in the creel fishery, but were still observed in high densities on creel grounds. Comparison with trawled areas showed some differences in density, the most notable being that the tall sea pen Funiculina quadrangularis was less abundant on trawled grounds, indicating an adverse effect of bottom-towed gear. Bycatch was assessed in two distinct fisheries and varied both between and within areas; however, levels of bycatch (both target and non-target species) in all areas were much lower than previous estimates from the trawl fishery. Additionally, in contrast to the trawl fishery, commercially exploited fish made up a small proportion of the bycatch in the Nephrops creel fisheries studied. The survival of Nephrops discards is considered to be high, although preliminary results suggest that predation by seabirds may cause significant mortality. The effects of ‘ghost fishing’ were investigated experimentally at two sites and it seemed that lost creels do not constitute a serious issue in this fishery. Creels were found to be very selective for their target species, with both target and non-target species being able to escape. Only a few crabs and a small proportion of the captured Nephrops died in the creels, indicating no evidence of a ‘re baiting’ effect from dead animals. Stress associated with the capture, storage and live transport of creel-caught Nephrops was found to be greatest during the transport process, during which Nephrops are kept out of water for long periods of time. Temperature was particularly important, suggesting cooling prior to and during transport was essential in order to ensure their survival. Reduced salinity was found to be a major source of stress. An assessment of the management measures implemented in the Torridon creel fishery show that escape gaps placed in creels are effective in enabling smaller Nephrops and other bycatch species to escape. Limiting effort of individual fishermen has been successful, but this has been followed by an increase in the number of boats fishing within the area, leading to an overall increase in effort. Management measures (both statutory and voluntary) currently applied in the Torridon area are discussed and considered in relation to other areas. It is concluded that creel fishing areas need to be considered on a case-by-case basis, accounting for biological characteristics of individual stocks, as well as management issues at a local scale. The findings of the present study are discussed in the context of providing a detailed description of the characteristics of the Nephrops creel fishery on the west coast of Scotland. Findings are also discussed in relation to other crustacean creel fisheries, enabling issues directly relevant to the specific fishery to be considered in a much broader context. The present study has been particularly valuable in a wider context, as Nephrops are found in a habitat which is very different from the majority of other commercially exploited crustaceans, and their life history characteristics are also different. This study provides an ideal platform to assess what general principles from other creel fisheries apply to the Nephrops creel fishery, as well as what characteristics are unique to this fishery.
10
Baldwin, Jesse H. "Variability in beach topography and forcing along Oak Island, North Carolina". View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/baldwinj/jessebaldwin.pdf.
Texto completo
11
Brouwer, Stephen Leonard. "An assessment of the South African east coast linefishery from Kei Mouth to Stil Bay". Thesis, Rhodes University, 1998. http://hdl.handle.net/10962/d1005076.
Texto completoResumen
During the period April 1994 and February 1996 as part of an investigation into the national Iinefishery, the east coast shore fishery and the recreational and commercial ski-boat fisheries were surveyed, at eight sites between Kei Mouth in the East and Stil Bay in the West. Roving creel, access point and aerial surveys were used. A questionnaire was developed for each sector to gather data on catch and effort, fisher demographics, economics, fisher attitudes towards, and knowledge of, the current management regulations and assess the efficacy of the fisheries inspectorate. During the access point survey the catch of 3273 fishers was inspected and 1556 interviews were conducted. Questionnaires were conducted on 118 recreational ski-boaters and the catch of 165 boats was inspected. 96 commercial skippers were interviewed and 230 had their catch inspected. Three aerial surveys of the entire area were conducted during which a total of 1067 shore fishers were counted giving a shore fisher density of 0.39 fishers.km⁻¹. The majority (99%) of participants in all sectors of the linefishery were male. The greatest number of participants were white, shore fishery 77% recreational ski-boat 98% commercial skiboat 89%, followed by coloured, asian and black people. To a large extent this reflects the income of various racial groups. Most fishers supported the current linefish management plan. However, when tested on their knowledge of the size limits, bag limits and closed seasons of their target species many shore fishers (59%) did not know them and a high proportion of fishers in all sectors had disobeyed at least one of the regulations (shore 50%, recreational ski-boat 70%, commercial ski-boat 56%). When compared to historical data the present catch per unit effort (CPUE) in all sectors has decreased. Most interviewees in the various sectors did not accept responsibility for the decline in CPUE, but attributed it to three principal reasons vis their perceived direct competitors, trawling and pollution. Analysis of the catch revealed that all sectors were multispecies fisheries, with each sector being characterised by a small number of target species. Catch composition differed significantly between the shore and ski-boat sectors, but there was significant overlap between the two skiboat sectors. Analysis of the catch in comparison to that reported to the National Marine Linefish System (NMLS) revealed that there was a substantial degree of under-reporting. There was little seasonal difference in effort in the shore fishery while the recreational ski-boat effort was highest in the summer and the commercial ski-boat effort was high in the winter. Effort in the shore and recreational ski-boat fisheries was concentrated over weekends while the commercial ski-boat effort was highest during weekdays. Total effort for the entire area was estimated at 903 186 (±1913) fisher days per annum in the shore fishery, 24 357 (±685) recreational ski-boat fisher days and 64 266 (±1686) commercial ski-boat fisher days. Expenditure and capital investment in the various sectors was calculated, as were earnings of the participants in the commercial ski-boat sector. The linefishery in the Eastern Cape was estimated to have a minimum capital investment in excess of R210 million and more than R32 million is spent annually on running costs. The commercial ski-boat fishery directly employed an estimated 3184 people. The economic implications of changes in CPUE for the commercial ski-boat fishery are considered, as are the benefits of a recreational angling licence. Management of the linefishery is discussed in relation to the findings of this study.
12
Pang, Oi-ting Brenda y 彭愷婷. "Climate change: the role of carbon dioxide". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46732937.
Texto completo
13
Hou, Huiyi y 侯慧仪. "Marine biofouling organisms respond to multiple stressors in a changing climate". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/194551.
Texto completoResumen
The marine environment is likely to experience profound climate change in the coming 100 years and beyond. Ocean acidification (OA) is one of the climate change issues attracting the attention of researchers all over the world. The decreasing pH of the oceans might threaten marine biofouling organisms. However, climate change is not only involved with ocean acidification (OA) but the change of other environmental variables, such as temperature and salinity. These environmental factors act as multiple stressors and synergistically affect shell-forming biofoulers, in which, the calcium carbonate skeleton structure plays an important role of protection. Previous studies regarding the response of marine biofoulers to the environmental stressors were generally summarized in this article. Then a calcifying biofouling tube worm, Hydroides elegans, were reared from larval stage to early juvenile stage under control and treatment conditions to examine the combined effects of temperature (24, 30°C), pH (8.1, 7.7) and salinity (34, 27ppt). Juvenile growth and chemical composition (Mg/Ca and Sr/Ca) of their calcareous tubes were tested and used as assessment of effects of the three environmental stressors. The experiment revealed that H. elegans was robust to the environmental change because juvenile development positively responded to temperature and the interaction between temperature and salinity. Other combinations did not exert significant effect. The results suggest the need of further study of proteomics and transcriptomics to reveal the mechanisms of calcification as well as long-term studies to examine the energy costs of adaptation. In addition, the non-significant chemical composition (Mg/Ca and Sr/Ca) of the tube of this organism suggest a need of further exploration of the same animal but not only focus on three factors but the seawater chemical composition as well.published_or_final_version
Environmental Management
Master
Master of Science in Environmental Management
14
Blandford, Nigel John. "An integrated conservation strategy for the north coast of Lantau Island". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31252540.
Texto completo
15
Choy, Suk-fong y 蔡淑芳. "Quaternary environmental changes and engineering properties of offshore soils in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245250.
Texto completo
16
Yu, Jieqiong y 余洁琼. "The effectiveness of extended producer responsibility in motivating eco-design changes: perspectives from China'selectrical and electronics industry". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B47185934.
Texto completoResumen
Extended producer responsibility (EPR) as a holistic approach to product stewardship has been increasingly incorporated into environmental policy agenda in the last two decades. One major expectation of EPR is to prevent environmental problems at source by providing appropriate incentives for product eco-design changes. However, available studies empirically examining the actual influence of EPR on eco-design are limited. This research therefore aims to fill the research gap by evaluating the effectiveness of existing EPR programmes in driving eco-design changes from the perspective of China’s electrical and electronic (EE) industry, and shed some light on the prospects of EPR development in China.
Based on the analytical framework developed from reconstructed intervention theory, three intensive empirical studies have been carried out. The first study examines the perception and responses of 50 China’s EE manufacturers regarding the EU EPR programmes (i.e. the WEEE and RoHS Directives). The second study investigates the responses of 36 China’s EE manufacturers to the Chinese EPR programmes (i.e. China WEEE and China RoHS legislation) and identifies possible factors that exert causal impact on the occurrence of eco-design. In order to gain a deeper insight into the practical manifestations of effective EPR implementation in the private sector, three company case studies have been conducted in the third stage of the research, serving as an important supplement to the first two studies.
The three studies show that EPR programmes in a stringent regulatory approach focusing on products’ environmental properties such as substance bans can exert strong influence on design changes. However, mandated recycling legislation seems to have little driving effect for companies to change product design. The research points to the weakness of collective producer responsibility that is currently adopted in many EU Member States for WEEE implementation in achieving continuous eco-design improvements. It highlights the significance of realising the principle of individual producer responsibility in EPR programmes for achieving this goal.
Based on an attributability assessment, the research further shows that there are a number of factors that influence the adoption of eco-design in China, and the link between legislative EPR programmes and eco-design is complex and evolving. Not only may the EPR programmes have different existing, anticipating and potential effect on the incorporation of eco-design, but they may have very different driving influence on environmental laggards and leaders.
In this regard, this research suggests that there is no one-stop solution for EPR in China. A mixed mechanism that integrates various policy instruments such as administrative, economic and informative instruments, in conjunction with cooperation and infrastructure facilities, would be the most effective means to implement EPR in the context of China, thereby achieving the goal of sustainable production and consumption.published_or_final_version
Kadoorie Institute
Doctoral
Doctor of Philosophy
17
Page, Andre Paul. "The barriers and opportunities of resource efficiency and cleaner production within a South African context". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2800.
Texto completoResumen
Thesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2017.This research study investigates how environmental tools such as Resource Efficiency and Cleaner Production (RECP) can contribute to sustaining and supporting economic growth in South Africa. Resource optimisation is crucial when considering the concept of sustainable development. It also contributes to addressing the challenges of global warming and climate change, which in turn threaten industrial growth and sustainability in the long term. The study places emphasis on the barriers that prevent industry from implementing RECP recommendations, and identifies opportunities that could potentially reposition businesses should they consider implementation. It also promotes other sustainability tools that are available through collaboration with international entities, and this could be of great benefit to the South African industry. Factors of unemployment and urbanisation restricts national growth to some degree, hence the study explores how RECP can contribute to job retention by introducing new resource optimisation methodologies for the manufacturing sector, Moreover, it examines the imbalance between the demand as well as limitations of these resources. Through the compilation of data collated from questionnaires completed by industry, government and civil society participants, this study looks at achieving a balance between environmental sustainability and growth. It also looks at aligning this balance with the integration of specific economic and environmental policies, which also includes social aspects. What comes through significantly in this research is the lack of awareness within industry in terms of RECP, as well as the importance of prioritising the uptake of environmental initiatives to ensure that industry is compliant with the stringent policies and legislation designed by government to drive the sustainability process. Consequently the study shows that communication between public and private sector, as well as the awareness raising and marketing of sustainability to consumers need to be improved. An analysis of the various government support mechanisms is conducted, in respect of how industry could potentially leverage growth and drive positive change within their businesses. In addition to RECP, emphasis is placed on other Sustainable Consumption and Production (SCP) initiatives and tools that could possibly entrench sustainable practices and help with their incorporation into their business strategies.
18
Li, Qinglan y 李晴岚. "Statistical and numerical studies of urbanization influence and climate change in South China". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45791041.
Texto completo
19
Vladimirova, Ekaterina. "Values for sustainable future: transforming values in the context of climate change and global environmental degradation". Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/241295.
Texto completo
20
Bastani, Parisa. "Essays in energy economics : emissions abatement, climate policy, and welfare". Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708324.
Texto completo
21
Makame, Makame Omar. "Vulnerability and adaptation of Zanzibar east coast communities to climate variability and change and other interacting stressors". Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011895.
Texto completoResumen
Climate variability and change as well as sea level rise poses significant challenges to livelihoods, water and food security in small island developing states (SIDSs) including the Zanzibar Islands. Thus, without planned strategic adaptation, the future projected changes in climate and sea level will intensify the vulnerability of these sensitive areas. This thesis is based on research conducted in two sites located in the north eastern parts of each island, namely Kiuyu Mbuyuni, Pemba Island and Matemwe, Unguja Island. The research focused firstly on assessing the vulnerability of these two coastal communities to climate variability and change and other stressors. This included investigation of (1) the perceptions of fishers, farmers and seaweed farmers regarding climate stressors and shocks and associated risks and impacts, (2) existing and possible future water and food security issues, and (3) household's access to important livelihood assets. This was followed by an exploration of the coping and adaptive responses of farmers, fishers and seaweed farmers to perceived shocks and stresses and some of the barriers to these responses. Lastly, an analysis of the implications of the findings for achieving sustainable coastal livelihoods and a resilient coastal community was undertaken. The general picture that emerges is that local people along the east coasts of both islands are already vulnerable to a wide range of stressors. Although variability in rainfall is not a new phenomenon in these areas, increasing frequency of dry spells and coastal floods resulting from the influence of El Niño and La Niña events exert enormous pressures on local activities (fishing, farming and seaweed farming) which are the crux of the local economy. The main argument of the study is that the nature and characteristics of these activities are the main source of sensitivity amongst these communities and this creates high levels of vulnerability to climate shocks and trends. This vulnerability is evidenced by the reoccurrence of localised food shortages and the observed food and water insecurity. The study found that food insecurity is a result of unreliable rainfall, drought and seasonality changes. These interacted with other contextual factors such as poor soil, low purchasing power and the lack of livelihood diversification options. In addition to exposure to these almost unavoidable risks from climate variability, the vulnerability of the local communities along the east coasts is also influenced by the low level of capital stocks and limited access to the assets that are important for coping and adaptation. Despite this, some households managed to overcome barriers and adapt in various ways both within the three main livelihood sectors (fishing, farming and seaweed farming) as well as through adopting options outside these sectors resulting in diversification of the livelihood portfolio. However, the study found that most of the strategies opted for by fishers, farmers and seaweed farmers were mainly spontaneous. Few planned adaptation measures supported by state authorities were observed across the sites, with the exception of the provision of motorised boats which were specifically meant to increase physical assets amongst fishers, reduce pressure in the marine conservation areas and prevent overfishing in-shore. Furthermore, numerous strategies that people adopted were discontinued when further barriers were encountered. Interestingly, some of the barriers that prevented households adapting were the same ones that forced households that had responded to abandon their adaptations. To increase resilience amongst east coast communities to current and future predicted changes in climate and sea level, the study argues that traditional livelihood activities (fishing, farming and seaweed farming) need to be better supported, and access to a range of livelihood assets improved. This may be achieved through increased access to local sources of water and facilitation of rainwater harvesting, expanding the livelihood options available to people and increasing climate change awareness, and access to sources of credit.
22
Guzy, Jr Darrel James. "20th century warming: what fractions are fromanthropogenic greenhouse gases and from natural on solar effects?" Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46732780.
Texto completo
23
Spencer, Erin Elizabeth. "Factors Controlling Alewife (Alosa psuedoharengus) Population Abundance among Four Rivers in Mid-Coast Maine". Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/SpencerEE2009.pdf.
Texto completo
24
Beck, Julia S. (Julia Samantha). "Downstream changes in river morphology as a result of dam developments". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52243.
Texto completoResumen
Thesis (MEng)--University of Stellenbosch, 2001.ENGLISH ABSTRACT: A dam can have a significant impact on the downstream river morphology by altering both the flow regime and the sediment load. The effect of a dam is dependent on factors such as the storage capacity relative to the mean annual runoff (MAR), the operation of the reservoir and the sediment yield of the catchment. Changes in the river morphology include the degradation and coarsening of the riverbed, generally closer to the dam, and aggradation further downstream where the sediment delivered by tributaries cannot be carried through because of the reduced sediment transport capacity of the river. The impact of a dam can stretch over several hundreds of kilometres. The main objective of this thesis was to gain a better understanding of the impacts that dams can have on the downstream river morphology. This was done by developing equations that can describe the channel geometry, investigating the effect of the presence of clay and silt on the sediment transport behaviour of sediments, as well as detailed evaluation of simulations carried out with a one-dimensional mathematical river model (MIKE 11). The calibrated regime equations were found to be comparable to other internationally developed regime equations and to be suitable for natural rivers. It was found, however, that these regime equations are not applicable to rivers downstream of dams that have highly unnatural release patterns. Further research is needed in this regard. By investigating the effect of cohesive sediments on the sediment transport behaviour of mixed sediments it was found that as little as 7% clay and silt in the bed could affect their sediment transport characteristics. A methodology was also developed by which the critical conditions for mass erosion of cohesive sediments can be described in terms of the applied stream power. Sediment transport equations were calibrated and verified in terms of the unit input stream power for fine and non-cohesivesediments. The sediment transport equation for fine sediments was implemented in MIKE 11. The simulations over a 40 km reach of the Pongola River downstream of Pongolapoort Dam, have shown that even when a large demand is placed on the stored water, and most of the smaller floods are therefore absorbed by the dam, the downstream impact can still be considerable, with as much as 5 m deep erosion in places. The sediment loads are generally reduced (by as much as 35%), but the effective catchment area downstream of the dam has been reduced by as much as 90%, indicating that substantial erosion had to have taken place in the river. Coarsening of the riverbed was also observed during the simulations.
AFRIKAANSE OPSOMMING: 'n Dam kan 'n aansienlike impak he op die riviermorfologie stroomaf daarvan, deurdat dit beide die vloei en sedimentlading drasties kan verander. Die effek van 'n dam hang van verskeie faktore af, soos die opgaarkapasiteit in vergelyking met die gemiddelde jaarlikse afloop (GJA), die bestuur van die dam en die sedimentlewering van die opvanggebied. Veranderings in die riviermorfologie behels die degradering van die rivierbed, sowel as die uitspoel van fyn materiaal uit die rivierbed, veral nader aan die dam. Deponering vind verder stroomaf van die dam plaas, waar die sediment wat deur die sytakke ingevoer word nie deurgevoer kan word nie, weens die verlaagde sedimentdravermoe van die rivier. Sodoende kan rivierlope oor honderde kilometers deur 'n dam bemvloed word. Die hoofdoel van die tesis was om meer insig te verkry oor die impak wat damme op die stroomaf riviermorfologie kan he. Derhalwe is vergelykings ontwikkel wat die riviermorfologie kan beskryf. Die effek van die teenwoordigheid van klei en slik op die sedimentvervoer-eienskappe is ondersoek, en gedetaileerde ontledings is met 'n een-dimensionele wiskundige riviermodel (MIKE 11) is gedoen. Daar is bevind dat die regime-formules goed vergelyk met ander intemasionaalontwikkelde formules en dat hulle geskik is vir toepassing op natuurlike riviere. Daar is egter gevind dat die formules nie geskik is vir riviere wat stroomaf Ie van damme wat hoogs onnatuurlike loslatings het nie. Verdere navorsing is op hierdie gebied nodig. Ondersoek na die effek wat klei en slik op die sedimentdravermoe het, het getoon dat slegs 7% klei en slik in die rivierbed die sedimentvervoer-eienskappe van mengsels van fyn en growwe materiaal kan bemvloed. 'n Metode is ontwikkel waarmee die kritiese toestande vir massa-erosie van kohesiewe sediment beskryfkan word in terme van die aangewende stroomdrywing teen die bed. 'n Sedimentvervoer-vergelyking in terme van die eenheids-insetstroomdrywing vir fyn en nie-kohesiewe sedimente is gekalibreer en geverifieer. Die nuwe sedimentvervoer-vergelyking vir fyn sedimente is gebruik in die MIKE 11 simulasies. Hierdie simulasies oor 'n 40 km loop van die Pongolarivier stroomaf van Pongolapoort Dam, het getoon dat selfs as daar 'n groot aanvraag op 'n dam se water geplaas word, en gevolglik meeste van die kleiner vloede deur die dam geabsorbeer word, die impak van die dam nogs steeds aansienlik kan wees, met soveel as 5 m diep uitskuring in plekke. Die sedimentladings het gewoonlik verminder (met soveel as 35%), maar die die effektiewe opvanggebiedarea stroomafvan die dam het met meer as 90% verminder, wat daarop dui dat daar aansienlike erodering in die rivier plaasgevind het. Die simulasies het ook getoon dat die hoeveelheid fyn materiaal in die rivierbed verminder het.
25
Rodriguez, del Rey Zoe. "Occurrence and Concentrations of Caffeine in Seawater from the Oregon Coast and Potential Effects on the Dominant Mussel, Mytilus californianus". PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/722.
Texto completoResumen
Caffeine, a biologically active drug with many known molecular targets, is recognized as a contaminant of aquatic systems including marine systems. Although the concentrations of caffeine reported from aquatic systems are low (ng/L to μ/L), harmful ecological effects not detected by traditional toxicity tests could occur as a result of caffeine contamination. The goals of this thesis project were to: 1) quantify concentrations of caffeine occurring in the coastal ocean off of the Oregon Coast and to determine if higher levels were correlated with proximity to caffeine pollution sources; and 2) investigate the sub-lethal cellular toxicity of environmentally relevant concentrations of caffeine on Mytilus californianus, an intertidal mussel that is one of the dominant species of the Oregon Coast. Caffeine was analyzed at 14 locations in the coastal ocean off of the Oregon Coast. Sampling locations were stratified between populated areas identified as having sources of caffeine pollution and sites located in sparsely populated areas not in proximity to major caffeine pollution sources. Caffeine concentrations were also measured in the major water body discharging near sampling locations. Caffeine was detected in water from the coastal ocean off of the Oregon Coast at concentrations ranging from below the reporting limit to 44.7 ng/L. The occurrence and concentrations of caffeine in the coastal ocean did not correspond well with pollution threats from population density and point and non-point sources, but did correspond with a storm event occurrence. Caffeine concentrations in rivers and estuaries draining to the coast ranged from below the reporting limit to 152.2 ng/L. Hsp70, a molecular biomarker of cellular stress, was used to investigate the sub-lethal toxicity of environmentally relevant concentrations of caffeine to the mussel M. californianus. Hsp70 concentrations in the gill and mantle tissue of mussels exposed to 0.05, 0.2, and 0.5 μ/L of caffeine for 10, 20, and 30 days were compared to basal levels in control mussels. Hsp70 in the gill tissue of M. californianus had an initial attenuation of the stress protein followed by a significant albeit moderate up-regulation relative to controls in all but the 0.5 μ/L treatment. Hsp70 in the mantle tissue of mussels exposed to caffeine did not differ from control mussels. This Study confirms the presence of caffeine in Oregon's coastal ocean and provides laboratory evidence that environmentally relevant concentrations of caffeine can exert an effect on M. californianus gill tissue at the molecular-level.
26
Hartmann, Holly Chris. "Stakeholder driven research in a hydroclimatic context". Diss., FIND on the Web, 2001. http://hdl.handle.net/10150/191254.
Texto completo
27
Maree, R. C. "Environmental influences on the daytime vertical distribution of Cape hakes and implications for demersal trawl estimates of hake abundance off the west coast of South Africa". Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1005122.
Texto completoResumen
The demersal fishery off the west coast of South Africa experiences decreased catches per unit effort of hake, Merluccius capensis and M. paradoxus, following the onset of strong south easterly winds. Research has demonstrated that, during daylight hours, Cape hakes migrate vertically in the water column in response to strong south easterly winds, decreasing their availability to the bottom trawl. Hydroacoustic, trawl and environmental data were collected off the West Coast during both calm and wind-swept periods in an attempt to understand the forces that initiate this behaviour, its spatial variability and the implications for demersal trawl estimates of abundance. Near-bottom currents appear to be the primary factor influencing the vertical distribution of the demersal fish community, of which hake constitutes a large proportion, during daylight hours. Correlation between wind and near-bottom currents suggest that the poleward component of the currents increase in velocity within eight hours following the onset of south easterly winds. The fish avoid boundary layers where currents change direction and speed dramatically, and seem to concentrate in waters with relatively stable current regimes. This result questions the assumption of CPUE-based assessment models that hake availability to the bottom trawl is constant or varies randomly. The incorporation of acoustic assessment techniques to demersal surveys has potential, but may be most valuable by supplementing swept-area estimates of abundance, since the sampling efficiency of these methods varies within the water column. The incorporation of wind indices and gear performance data to Cape hake assessment models have been identified as useful considerations for the future.
28
Walton, Sara y n/a. "Contesting natures : a discourse analysis of natural resource conflicts". University of Otago. Department of Management, 2008. http://adt.otago.ac.nz./public/adt-NZDU20080404.142212.
Texto completoResumen
This research explores the discursive formations involved in two environmental conflicts during which organisations were not permitted to carry out their proposed extractive activities. The conflicts were based on the West Coast of the South Island in New Zealand. The first involved sustainable native logging and the second was over the siting and extension of a gold mine.
Extensive archival and media searches were carried out to generate data on the conflicts. Interviews were also conducted to investigate the community position in more depth. The discourse theory of Laclau and Mouffe (2001 [1985]) is drawn upon as a framework to make sense of the conflicts. This framework was particularly useful as it enabled a close and careful examination of the antagonisms and addressed some of the ideological and power concerns with stakeholder analysis. The analysis involved identifying nodal points, subjectivity, subject positions and floating signifiers, which enabled certain hegemonic constructions.
The two conflicts were considerably different. The hegemonic constructions were quite similar and the notion of �being green� emerged as an antagonism that was at the heart of the conflicts and a key to understanding why these business organisations were unsuccessful. That is, who or what is given meaning as �being green� negates and de-legitimates other activity that is not deemed to be green. In these conflicts business organisations extracting natural resources and subjects supporting these organisational activities could not be green - when being green was constituted in terms of the clean green discourse operating economically and socially within New Zealand (see Bell, 1996). Consequently, not being green was deemed to be outside of what we see as New Zealanders as being important and thus should not occur in this country.
This research has implications for business organisations in New Zealand dealing with greening issues, especially as external stakeholders can have considerable influence on organisational activities. Theoretically it argues for a discursive approach to organisational stakeholder analysis in order to address power and subjectivity and for the organisation and natural environment literature to recognise the possibility of multiple meanings of nature. In particular, this thesis contributes to current organisation studies literature by explicitly focusing on �nature� as a concept. It shows that the meaning attributed to nature is a political process which can have consequences for preventing or enabling significant business organisational activities.
29
Fouty, Suzanne Catherine. "Current and historic stream channel response to changes in cattle and elk grazing pressure and beaver activity". Thesis, view abstract or download file of text, 2003. http://wwwlib.umi.com/cr/uoregon/fullcit?p3080584.
Texto completoResumen
Thesis (Ph. D.)--University of Oregon, 2003.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 634-646). Also available for download via the World Wide Web; free to University of Oregon users.
30
MacKendrick, Katharine. "Climate Change Adaptation Planning for Cultural and Natural Resource Resilience: a Look at Planning for Climate Change in Two Native Nations in the Pacific Northwest U.S". Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/10022.
Texto completoResumen
xii, 172 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.The literature indicates that for indigenous peoples the environmental impacts of climate change and some proposed solutions threaten lifeways, subsistence, economic ventures, future growth, cultural survivability, rights, land ownership, and access to resources. However, limited understanding and awareness of the vulnerability and capacity of American Indian and Alaska Native tribes and of climate change impacts at the local level affect climate policymaking, planning, and equity. Case studies with the Coquille and Hoopa Valley Indian tribes in the Pacific Northwest U.S. explore the key considerations in planning for climate change adaptation, particularly for cultural and natural resource resilience. Document analysis and semi-structured interviews offer insight on the risks the tribes face and the role of traditional and local knowledge and experience in planning for climate change adaptation. Conclusions offer information useful in planning for climate impacts, local-level climate adaptation research, and climate policy development at the local to global levels.
Committee in Charge: Dr. Michael Hibbard, Chair; Dr. Cassandra Moseley; Kathy Lynn
31
Wearing, Catherine Louise. "Changes in fluxes of dissolved organic carbon (DOC) from small catchments in central Scotland". Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/368.
Texto completoResumen
Concentrations of dissolved organic carbon (DOC) measured within water bodies have been increasing on a global scale over the last two decades. Changes in temperature and rainfall have been shown to increase the production and export of DOC from catchments with peat soils in the UK (Freeman et al., 2001). However it is not clear whether increases in DOC concentrations are caused by production increases induced by temperature changes or by a greater incidence of high flows induced by rainfall changes. Increases in both temperature and rainfall have been predicted in Scotland over the next few decades (Kerr et al., 1999) which may further increase current DOC concentrations and exports. The implications of this include both a decrease in water quality and an increase in mobility of metals in upland water bodies. The overall aim of the thesis is to determine if the relationship between dissolved organic carbon (DOC) concentrations and discharge has changed over a 20 year period in small stream catchments in Scotland, in order to better understand the role of hydrology, in driving changes in DOC concentration. To achieve this streams draining two coniferous forest sites and one moorland site were monitored intensively between June 2004 and February 2006. Analysis of the relationship between DOC and discharge, within the catchments, identified the importance of the amount of precipitation falling on the catchment, antecedent precipitation and season, on the concentration of DOC that was measured within the stream. Models were then developed using variables to represent these drivers in terms of both the production (seasonal sine values and 14 day average temperatures) and movement (log of discharge (log Q), days since previous storm event and rising or falling stage) of DOC. In the Ochil Hills catchment, the best predictive model, used 4 hour average discharge and 1 day average 30cm soil temperatures (R2= 0.88). In the Duchray and Elrig catchments, the best predictive models produced used discharge and seasonal sine values; the strength of the model was greater in the Elrig (R2= 0.80) than the Duchray (R2= 0.48) catchment. The strength of the regression models produced highlighted the importance of precipitation in the movement of DOC to the stream and temperature variables representing production in the surrounding catchment. To determine if dissolved organic carbon (DOC) concentrations had changed within the three study catchments, since previous research was conducted at the same sites in the early 1980s and 1990s (Grieve, 1984a; Grieve, 1994), then regression analysis conducted in the previous research was repeated, so changes in the DOC and discharge relationship could be identified. Analysis of the Ochil Hills regression equations identified higher log of discharge and lower temperature and seasonal sine values in the present study (2004-06), when compared to the previous study (1982-83). This suggests that more DOC is now available for movement from the soil, and that the difference between winter and summer DOC production has decreased, potentially because of increasing temperatures. This would explain the limited increase in DOC concentration within the Ochil Hills stream. In the Duchray and Elrig streams, a large increase in DOC was identified at all discharges when all the models produced were compared between the two sampling periods (1989-90 and 2004-06). The increasing trend in DOC concentrations is too large to have been produced by change in temperature alone and it is suggested that the measured reduction in acidic deposition has resulted in the increased DOC concentrations measured in the Duchray and Elrig. The results from this research have identified that concentrations of DOC have increased in Scottish streams over the last 20 years and that the increases in DOC have been induced, potentially by temperature changes in climate. However, changes in temperature are not the only driver of this change as the reduction in acidic deposition is potentially more important, specifically in areas with base poor geology such as the Duchray and Elrig catchments.
32
Nancarrow, Tanya Lawrene. "Climate change impacts on dietary nutrient status of Inuit in Nunavut, Canada". Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112545.
Texto completoResumen
This thesis characterizes the nutritional implications of climate change impacts on the traditional food system of Inuit in Nunavut, Canada. Both focus groups and food frequency questionnaires were used in collaboration with two communities to describe current climate change impacts on traditional food and define nutrient intake. Currently, both communities experience climate-related changes to important species which provide high levels of key nutrients. If climate changes continue to impact traditional food species, serious nutritional losses may occur unless healthy alternatives can be found. Policy should support Inuit communities to maintain optimal nutrition in the face of climate change.
33
Caldecott, Benjamin. "Stranded assets and environment-related risk". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:36137d36-8392-4ce9-8a51-709bc6495a17.
Texto completoResumen
This thesis represents the first comprehensive attempt at providing conceptual and scholarly coherence to the topic of stranded assets and the environment. Over the last five years the topic has risen up the agenda and has become of significant interest to scholars and practitioners alike, as it has influenced a number of pressing issues facing investors, companies, policymakers, regulators, and civil society in relation to global environmental change. The thesis reveals how the topic developed and emerged, notably through a unique first-person account based on autoethnography and close dialogue. Four self- contained papers demonstrate the wide applicability of stranded assets, and further existing, relatively well-developed literatures (namely carbon budgets and stranded costs) and also two much less developed literatures (namely the calibration of climate policy to minimise stranded assets and policy mechanisms to quickly and efficiently strand assets). Though a significant amount has been written on stranded assets over a short period, there remain significant gaps in the literature. The thesis identifies substantial research opportunities, particularly to better connect our understanding of physical and societal environment-related risks; to improve our knowledge of perception and behaviour in relation to the creation and management of stranded assets; to expand the scope of work into new sectors and geographies; and to place stranded assets in an appropriate historical perspective. Stranded assets is, if anything, a geographical concept. The thesis makes the case for economic geography as the disciplinary home for stranded assets. The sub-discipline can both contribute to the development of stranded assets as a scholarly endeavour and itself benefit from interacting with a topic that intersects with some of the most pressing contemporary issues related to environmental sustainability.
34
Apostolis, Juanita Joleen. "A critical analysis of Global Warning coverage in the National Geographic (2000-2010)". Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/1607.
Texto completoResumen
National Geographic is a magazine that inspires people to care about the planet through its articles of exploration, education, and conservation. Magazines are a significant source of knowledge and compete with a variety of other media, constantly rethinking where they can improve in comparison to other media. Research in this dissertation shows that some magazines offer high quality imagery for artwork, photos and advertisements, which remains critical for industries and readers. They often offer greater depth than radio, TV, or even newspapers, so that people interested in an analysis of news and events still depend on magazines for informative and general news. People often turn to media—such as television, newspapers, magazines, radio, and Internet—to help them make sense of the many complexities relating to environmental science and governance that (un)consciously shape our lives. Global warming, as a subject, demands both political and personal responses in all parts of the world, and effective decision making at both scales depends on timely, accurate information, according to Shanahan (2009:145). The quality and quantity of journalism about climate change will therefore be key in the coming years. National Geographic comprises a variety of themes, such as environment, science, wildlife, travel and photography. This study is an analysis of the writing and photography related to one theme - global warming. It provides a critical analysis of the coverage of the global warming discourse in one magazine, examined over an eleven-year period from 2000 to 2010. This theme is powerful in that it represents ethical responsibility and concern for nature and our world and the analysis attempts to define the objects of discourse within the coverage, thus, evaluating if the format of the coverage informs and educates the audience about global warming.
35
Matavire, Melisa M. "Impacts of sugarcane farming on coastal wetlands of the north coast of Zululand, Kwadukuza, South Africa". Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97121.
Texto completoResumen
Thesis (MSc)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Wetlands are key to providing important ecosystem goods and services yet they are under threat from a number of anthropogenic activities. In particular, in this study area, agriculture in the form of sugarcane farming is a threat to wetlands as sugarcane is reliant on a good water supply. The impacts of sugarcane farming emanates from the fact that sugarcane is a mono crop that requires wetland resources and uses a lot of pesticides and fertilisers. Despite the assumed contribution of sugarcane farming to wetland loss and degradation, few studies have quantitatively assessed the spatio-temporal changes in wetland extent as well as changes in water quality because of this activity. This study assesses the impacts of sugarcane farming on wetland extent and water quality in two coastal wetlands of KwaDukuza, North coast of Zululand, South Africa. Specifically this study sought to (i) assess the impacts of sugarcane farming on the spatial extent of wetlands between 1959 and 2012, (ii) determine if sugarcane farming negatively affect water quality within the wetlands and (iii) evaluate the perceptions of local farmers regarding impacts of sugarcane farming on wetlands. Results of the study indicated an increase in the extent of Zinkwazi sugarcane fields from 62.3% to 67% between 1959 and 1989 and Nonoti sugarcane fields’ extent increased from 50.5 % to 56.4% between 1959 and 2000. The last decade from the year 2000 showed gradual decrease in the area of wetland farmed by sugarcane due to the global sugar price remaining static while the cost of farming inputs increased and due to conversion of some farms to urban developments. Unfortunately, this has not lead to an increase in wetland area as the waterfront type developments, as well as a formal settlement have replace the sugarcane in the wetlands. Water was analysed for nitrogen (N), phosphorus (P) and potassium (K) and results for both Zinkwazi and Nonoti indicated an increasing trend of N and P from upstream to the middle region of the rivers and a decreasing trend of the N and P from the middle region to downstream. Sugarcane farming does not take place below the middle region and so does not provide fresh sources of these nutrients. The downstream area where the N and P decrease also coincides with the area of the river under tidal influence such that the N and P are being diluted by the incoming tidal seawater. K showed an increasing trend from upstream to downstream and its values were higher than N and P. Concentrations of N and P above the South African water quality guidelines for aquatic ecosystem were recorded in the middle region. Furthermore, farmers’ perceived wetlands to have been transformed to agricultural land and related these changes to their sugarcane farming activities. It can thus, be concluded that sugarcane farming has resulted in wetland loss as well as deterioration of water quality within the Zinkwazi and Nonoti wetlands in KwaDukuza. In that regard, there isneed to engage farmers in wetland management programs in order to reduce the negative environmental impacts associated with sugarcane farming in wetlands.
AFRIKAANSE OPSOMMING: Vleilande is die sleutel tot die verskaffing van ‘n belangrike ekosisteem dienste, maar hulle is onder ‘n bedreiging deur 'n aantal menslike aktiwiteite. In besonder in hierdie studie area, is Argriculture in die vorm van suikerriet boerdery is bedraging vir vleilande, en suikerriet is afhanklik van 'n goeie watervoorraad. Ten spyte van die veronderstelde bydraes van suikerriet boerdery, is die vleiland aan die agteruitgang, 'n Paar studies het kwantitatief die tydruimtelike veranderinge in die vleiland, sowel as veranderinge in die gehalte van water as gevolg van hierdie aktiwiteit waargeneem. Spesifiek is hierdie studie gepoog om (i) te bepaal wat die impak van suikerriet boerdery op die ruimtelike omvang van die vleiland tussen 1959 en 2012 is, (ii) bepaal of suikerriet boerdery negatief beïnvloed is deur die gehalte van water in die vleilande en (iii) die persepsies van plaaslike boere rakende die evalueering en impak van suikerriet boerdery op die vleilande. Resultate van die studie het aangedui 'n toename in die omvang van Zinkwazi suikerriet velde van 62,3% tot 67% tussen 1959 en 1989, en die Nonoti suikerriet velde toegeneem het met 50,5% tot 56,4% tussen 1959 en 2000. Die laaste dekade van die jaar 2000 het geleidelike afname in die area van die vleilande getoon, omdat suikerriet as gevolg van die globale suiker prys die koste van boerdery-insette verhoog het, en dit het gelei tot die omskakeling van 'n paar plase na stedelike ontwikkelings. Ongelukkig het dit nie gelei tot 'n toename in die vleiland gebiede nie, met die gevolg die waterfront tipe ontwikkelings, asook 'n formele nedersetting, vervang die suikerriet in die vleilande. Water is ontleed vir N, P en K en resultate vir beide Zinkwazi en Nonoti, het aangedui 'n toenemende tendens van stikstof en Fosfor. Dit gaan stroomop na die middel-streek van die riviere en 'n dalende neiging van die N en P uit die middel streek stroomaf. Suikerriet boerdery vind nie plaas onder die middel streek nie, en so is daar nie vars bronne, wat van hierdie voedingstowwe verskaf nie. Die stroomaf gebied waar die N en P ‘n afname het, val ook saam met die gebied van die rivier onder die gety , en dit beinvloed sodanig dat die N en P se water verdun word deur die inkomende gety se seewater. K het 'n toenemende neiging van stroomop en stroomaf en sy waardes is hoër as van die N en P. Konsentrasies van N en P bo die Suid-Afrikaanse water standaard riglyne is in die middel streek aangeteken. Verder, beskou boere dat die vleilande behoort te verander om die landbougrond en verwante veranderinge aan hul suikerriet boerdery en aktiwiteite. Ons kan dus aflei dat suikerriet boerdery het gelei tot die vleiland se verlies asook die verandering in die watergehalte in die Zinkwazi en die Nonoti vleilande in KwaDukuza. In dié verband is dit nodig dat die boere in die vleiland by programme betrek word ten einde die negatiewe omgewingsimpakte wat met suikerriet boerdery gepaard gaan in vleilande te verminder.
36
Thornton, Matthew Jaeger. "Modal vehicle activity on freeways and freeway onramps : an assessment of the oxides of nitrogen emissions impacts resulting from changes in vehicle operating mode due to ramp metering systems". Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/20785.
Texto completo
37
Bradbury, James. "Computational hypothesis generation with genome-side metabolic reconstructions : in-silico prediction of metabolic changes in the freshwater model organism Daphnia to environmental stressors". Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8437/.
Texto completoResumen
Computational toxicology is an emerging, multidisciplinary field that uses in-silico modelling techniques to predict and understand how biological organisms interact with pollutants and environmental stressors. Genome-wide metabolic reconstruction (GWMR) is an in-silico modelling technique that aims to represent the metabolic capabilities of an organism. Daphnia is an emerging model species for environmental omics whose underlying biology is still being uncovered. Creating a metabolic reconstruction of Daphnia and applying it in an environmental computational toxicology setting has the potential to aid in understanding its interaction with environmental stressors. Here, the fist GWMR of D. magna is presented, which is built using METRONOME, a newly developed tool for automated GWMR of new genome sequences. Active module identification allows for omics data sets to be integrated into in-silico models and uses optimisation algorithms to find hot-spots within networks that represent areas that are significantly impacted based on a toxicogenomic transcriptomics dataset. Here, a method that uses the active modules approach in a predictive capacity for computational hypothesis generation is introduced to predict unknown metabolic responses to environmentally relevant human-induced stressors. A computational workflow is presented that takes a new genome sequence, builds a GWMR and integrates gene expression data to make predictions of metabolic effects. The aim is to introduce an element of hypothesis generation into the untargeted metabolomics experimental workflow. A study to validate this approach using D. magna as the target organism is presented, which uses untargeted Liquid-Chromatography Mass Spectrometry (LC-MS) to make metabolomics measurements. A software tool MUSCLE is presented that uses multi-objective closed-loop evolutionary optimisation to automatically develop LC-MS instrument methods and is used here to develop the analytical method.
38
Yazzie, Kimberly Crystal. "Watershed Response to Climate Change and Fire-Burns in the Upper Umatilla River Basin Using the Precipitation Runoff Modeling System". PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3127.
Texto completoResumen
This study provides an analysis of watershed response to climate change and forest fire impacts, to better understand the hydrologic budget and inform water management decisions for present and future needs. The study site is 2,365 km2, located in the upper Umatilla River Basin (URB) in northeastern Oregon. The Precipitation Runoff Modeling System, a distributed-parameter, physical-process watershed model, was used in this study. Model calibration yielded a Nash Sutcliffe Model Efficiency of 0.73 for both calibration (1995-2010) and validation (2010-2014) of daily streamflow. Ten Global Climate Models using Coupled Model Intercomparison Project Phase 5 experiments with Representative Concentration Pathways 4.5 and 8.5 (RCP), were used to observe hydrologic regime shifts in the 2020s, 2050s, and 2080s. Mean center timing of flow occurs earlier in the year in both pre- and post-fire conditions, where there are increased winter flows and decreased summer flows throughout the 21st century. Change in temperature and percent change in precipitation is more variable in the summer than winter increasing over time, with a slight decrease in winter precipitation in the 2080s in RCP 8.5. Temperature increases 1.6°C in RCP 4.5 and 3.3°C in RCP 8.5 by the end of the 21st century. The ratio of Snow Water Equivalent to Precipitation decreases 96% in the 2080s in RCP 8.5 before forest cover reduction, and decreases 90-99% after forest cover reduction. Potential basin recharge and the base-flow index are both sustained throughout the 21st century with slight declines before forest cover reduction, with an increase in basin recharge and increase in base-flows in the 2080s after fire-burns. However, the simulated sustained base-flows and area-weighted basin recharge in this study, do not take into account the complex geologic structure of the Columbia River Basalt Group (CRBG). A more robust characterization and simulation of URB aquifer recharge would involve coupling the PRMS model with a groundwater model in a future study. Although groundwater recharge in the CRBG in the URB is not well understood, the long-term decline of groundwater storage presents a serious environmental challenge for the Confederated Tribes of the Umatilla Indian Reservation and communities in the URB.
39
Lombard, Andrea. "Wind energy landscapes, place attachment and tourism in the Route 27/West Coast Region of South Africa". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79872.
Texto completoResumen
Thesis (MA)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The West Coast Region (WCR) of the Western Cape Province in South Africa is earmarked for at least 13 windfarm developments. These proposed developments represent an investment in and a movement towards cleaner and alternative ways of energy generation. All developments that will alter the environment or landscape are usually received with some sort of opposition. The aim of this study was to determine whether or not the presence of wind turbines in the form of wind farms will have any affect on the sense of place of insiders of (residents) and outsiders (visitors) to the West Coast Region, the insiders’ attachment to their natural landscapes and the outsiders’ experiences of the region. In the context of multiple issues arising from a very complex discourse around the possible effects that the proposed windfarms are perceived to have in the WCR, this study approached the research topic from three perspectives of inquiry: (1) windfarms and people’s place attachment; (2) windfarms and landscape aesthetic and function interference; and (3) windfarms and its effect on tourism. The study area includes 15 towns of three subregions of the WCR, namely the Swartland, West Coast Peninsula and Bergrivier subregions. The research objectives are seven fold, namely (1) to establish a solid base and understanding of the concepts and constructs related to wind energy, landscape aesthetics and place attachment; (2) to review appropriate case studies reported in the international literature and apply relevant methodologies in this study; (3) investigate theories, types and models of public decision making to explore the degree to which these could be applied to windfarm support or objection in the WCR; (4) to critique current policies in windfarm establishment and discover whether and how these shape social objection to or support for windfarm development in the WCR; (5) to establish the perceptions and attitudes relating to wind turbines of three groups of actors (tourism industry, tourists and residents) in the WCR by conducting questionnaire surveys in 15 West Coast towns and villages and interpret these views in relation to the impacts of wind turbines on the local landscape; (6) to determine the insiders’ place attachments to the WCR, whether the presence of wind turbines will affect these attachments and whether their attachments influence decisions to support or oppose the proposed windfarm developments; and (7) to assess the extent to which the presence of wind turbines will affect the tourism value of the region. Primary data was further strengthened by semi-structured interviews, informal conversations and observation at public participation and specialized group meetings. Data was analysed using SPSS, Excel and ArcGIS. The findings indicate that respondents are concerned with issues related to the sustainability of the natural environment and that the residents of the WCR possess a strong sense of attachment to the region, but no clear indication was found that their place attachment serve as a reason for their opposition to the proposed windfarm developments. Although the support for windfarm development decreases from a national to a regional level and to the local level of in or close to the towns in which respondents reside, their opposition to windfarm development in the region cannot only be regarded as simple not-in-my-backyard (NIMBY) attitudes. Seventy-five per cent of the respondents regard the physical landscape of the WCR as very special, but would still support the development of windfarms in the region indicating that the respondents do not believe the construction of wind turbines in the WCR landscapes will influence the special character of landscapes negatively. There is no indication presently that the tourism industry would be affected negatively by windfarm development in the region as both residents and visitors do not believe that windfarms deter tourists from visiting certain areas and more than 90% of visitors indicated they would return to the WCR after a number of windfarms have been developed. It is recommended that a post-development impact study be conducted to determine the attitudes toward windfarm development in the WCR following the deployment of wind turbines.
AFRIKAANSE OPSOMMING: Die Weskus-streek in die Wes-Kaap provinsie van Suid-Afrika word geoormerk vir ten minste 13 windplaas ontwikkelinge. Hierdie voorgestelde ontwikkelinge verteenwoordig ‘n belegging in en ‘n beweging na skoner en alternatiewe maniere van energieopwekking. Alle ontwikkelinge wat die omgewing of landskap sal verander word gewoonlik ontvang deur ‘n mate van teenkanting. Die doel van hierdie studie was om te bepaal of die teenwoordigheid van windturbines in die vorm van windplase enige invloed op die plekbewustheid van inwoners van en besoekers aan die Weskus-streek, hulle gehegdheid aan die streek se natuurlike landskappe en besoekers se ervarings van die streek sal uitoefen. Binne die konteks van verskeie kwessies met hul oorsprong vanuit ‘n baie komplekse diskoers rondom die moontlike effekte wat vermeen word die voorgestelde windplase op die Weskus-streek sal hê, benader hierdie studie die navorsingsonderwerp vanuit drie navraagsperspektiewe: (1) windplase en mense se plekgehegdheid; (2) windplase en landskap estetiese en funksie steuring; en (3) windplase en die effek daarvan op toerisme. Die studie area sluit 15 dorpe uit drie substreke van die Weskus-streek in, naamlik die Swartland, Weskus Skiereiland en Bergrivier substreke. Die navorsingsdoelwitte is sewevoudig, naamlik (1) om ‘n konseptuele basis en verstaan van konsepte en konstrukte geassosieerd met windenergie-opwekking, landskap estetika en plekgehegdheid te kweek; (2) om toepaslike gevallestudies te hersien en sommige relevante metodologie vir die studie aan te wend; (3) om teorieë, tipes en modelle van publieke besluitneming te ondersoek ten einde te bepaal tot watter graad dit aangewend kan word tot windplaasondersteuning of teenkanting in die Weskus-streek; (4) om kritiek te lewer op huidige beleide van windplaasontwikkeling en te ontdek tot watter mate en hoe dit sosiale teenkanting of ondersteuning van windplaasontwikkeling in die Weskus-streek vorm; (5) om die persepsies en houdings van drie groepe deelnemers (die toerisme industrie, toeriste en inwoners) in die Weskus-streek te bepaal deur vraelysopnames in 15 Weskus dorpe te doen en hierdie sienings in verhouding met die impakte van windturbines op die plaaslike landskap te interpreer; (6) om die inwoners se plekgehegdheid tot die Weskus-streek te bepaal en of die teenwoordigheid van wind turbines hierdie gehegdheid sal affekteer en of hul gehegdheid besluitneming rakende die ondersteuning vir, of teenkanting teen, windplaasontwkkeling beïnvloed; en (7) om te bepaal tot watter mate die teenwoordigheid van windturbines die toerisme waarde van die streek sal affekteer. Primêre data is verder versterk deur semi-gestruktureerde onderhoude, informele gesprekke en waarneming by publieke deelname sessies en gespesialiseerde groepsvergaderings. Data is ontleed deur middel van SPSS, Excel en ArcGIS. Daar is bevind dat respondente besorg is oor kwessies rondom die volhoubaarheid van die natuurlike omgewing en dat die inwoners van die Weskus-streek ‘n sterk gehegtheid aan die streek het, maar geen definitiewe aanduiding is gevind dat hulle gehegdheid aan die streek as ‘n behoorlike rede vir hul teenstand teen die voorgestelde windplase aangevoer kan word nie. Alhoewel ondersteuning vir windplase afneem vanaf nasionaal na streeksvlak en die plaaslike vlak van binne of naby die dorp waar respondente woon, kan teenkanting teen die ontwikkeling van windplase in die streek nie slegs eenvoudig as ‘n nie-in-my-agterplaas houding (NIMAP) beskou word nie. Vyf-en-sewentig persent van die respondente ag die fisiese landskap van die Weskus-streek as baie spesiaal, maar ondersteun steeds windplaasontwikkeling in die streek wat aandui dat die respondente nie van mening is dat die oprigting van windturbines in die Weskus-streek landskappe die spesiale karakter van hierdie landskappe negatief sal beïnvloed nie. Daar is tans geen aanduiding dat die toerismebedryf negatief deur windplaasontwikkeling beïnvloed sal word nie aangesien beide inwoners en besoekers aangedui het dat hul nie van mening is dat windplase toeriste sal verhinder om sekere areas te besoek nie. Negentig persent van besoekers het aangedui dat hul steeds sal terugkeer na die Weskus-streek ná die ontwikkeling van ‘n aantal windplase. Dit word aanbeveel dat ‘n ná-ontwikkeling impakstudie onderneem word om die houdings jeens windplaasontwikkeling in die Weskus-streek ná oprigting van die turbines te ondersoek.
40
MacIntosh, John 1967. "The influence of heavy metals on the diet changes of Neoperla (Plecoptera) in the northwest Miramichi River, New Brunswick /". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79038.
Texto completoResumen
In the summers 1997, 1998 and 1999, over 100 aquatic invertebrate kick samples were collected in the Northwest Miramichi River of northeastern New Brunswick to examine the effects of chronic heavy metal exposure on the aquatic predatory Plecoptera community. In the group of predators, Neoperla (Plecoptera) was numerically dominant and gut content identifications were used to determine food chain and life cycle stages. Neoperla diet analysis indicated the Chironomidae (Diptera) as the dominant prey with predation upon Trichoptera and Ephemeroptera influenced by the life cycle stage of the predator. Gut content totals were analysed for predatory diet changes due to heavy metal contamination exposure. The Neoperla community indicated a prey shift from a Chironomidae based diet to one including a higher percentage of Ephemeroptera and Trichoptera earlier in the predators life history when compared with upstream control sites. Neoperla diets maintained their shift from the control station diets as the downstream movement of heavy metal contaminated water mixed and dissipated within the study area.
41
Rickard, Darcel. "Community Based Coastal Monitoring: Developing Tools For Sustainable Management". The University of Waikato, 2008. http://hdl.handle.net/10289/2247.
Texto completoResumen
Burgeoning coastal development, recreational use, and the future affects of climate change are placing increasing strain on regulators to manage risk associated with coastal hazards. Low-lying coastal communities in particular are vulnerable to a range of natural hazards including coastal erosion, storm surge inundation, tsunami and water safety that come with varying levels of risk to life and property. New Zealand's coastal hazard monitoring network is patchy and resources are limited. As a consequence there is considerable potential for coastal communities are going to need to take a more active role in monitoring their environment and building data bases and knowledge that can be used to better manage their coast. This paper describes simple methodologies based on the needs of various community groups and sound science principles that can be used to monitor beaches and the coastal environment. By employing these tools councils, technical experts and community groups will be able to make better-informed decisions for managing activities in the coastal environment. One of the keys to the successful uptake of a monitoring programme by a community group is its relevance to the group. The programme and the tools provided must fit the interests, needs, capability and resources of the group. This project develops tools for coastal monitoring and targets coastal community groups such as Coast Care, Coastal Hapu, Secondary Schools, and Surf Life Saving Clubs. The monitoring methodologies have been developed in consultation with Tainui ki Whaingaroa hapu, Raglan Area School, and the Waikato Beach Care and Coast Care Bay of Plenty. Successful methodologies for measuring changes on the coast are also those that are matched to the type of beach, use appropriate equipment, collect structured data, provide data to which analysis can be applied, incorporate local knowledge of the environment, and feed results back to the community and other interested parties such as councils and science organisations. This project provides the target groups with simple monitoring methodologies, field forms/checklists, and appropriate survey and measurement equipment (which have undergone field trials) to carry out coastal monitoring. A web-based facility has been developed to input, check and store data; and provide immediate feedback using graphs and images. It also provides background information on coastal processes relevant to monitoring programmes. In this manner, a scientifically robust data set is collected and stored within a secure and future proofed archive, providing valuable information to coastal groups for years to come. Although the primary objective of this research is to develop a means for coastal communities to monitor changes in their environment, there are additional benefits associated with engaging communities in the study of their environment. These benefits include increasing awareness of coastal hazards, capacity building, providing valuable educational resources, and improving the temporal and spatial data coverage of information for the New Zealand coastline.
42
David, Clive Addison. "Post-harvest floor changes and nitrogen mobilization in an Engelmann spruce-subalpine fir forest". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26986.
Texto completoResumen
Engelmann spruce-subalpine fir [Picea engelmannii Parry ex Engelm.-Abies lasiocarpa (Hook.) Nutt.] (ESSF) forests occupy large portions of western North America, and of British Columbia (B.C.) in particular. These areas represent a harsh environment for plant growth. The ESSF forests of B.C. have presented serious problems of regeneration following harvesting; several factors stimulated speculation as to whether N supply limitations were involved. This study was intended to highlight the post-harvest N dynamics of an ESSF forest, and the implications of the latter for silvicultural practices. Its general objectives included characterization of the post-harvest assart effect, and investigation of the N status and growth of advance regeneration. These were achieved by means of a comparative study of an age sequence of harvested sites.
The assart effect lasted for at least eight years after harvesting, with a peak of change between years three and six. There were no major physical changes in the forest floor. Low C/N ratios between 19 and 32 were believed to have contributed to increased N availability. ESSF forests may have a generally higher level of N availability than previously supposed. The advance regeneration benefited from the assart effect. Nutrient uptake appeared to increase generally from at least three years after harvesting; increases of up to 78% were noted for N. There appeared to be no general macronutrient or micronutrient limitation to growth. However, evidence of S deficiencies was encountered in some trees. Moreover, the critical levels used for N may be in need of revision. A revised critical level of 1.40% for foliar N concentrations is proposed for subalpine fir advance regeneration. If this is accurate, regeneration may have been at least temporarily N-limited from year eight after harvesting. A more rigorous investigation of these possibilities is needed.
The cutting method applied to the sites approximated a one-cut shelterwood method. The method as encountered in this study should not be considered a viable silvicultural option for similar ESSF forests. Its successful application would involve some degree of forest floor manipulation to improve seedbed conditions and soil microclimatic regimes. The findings of this study demonstrate that the environmental and biological characteristics of ESSF forests make high levels of planning and care a prerequisite for the success of silvicultural
practices. The question of what comprises realistic growth and yield expectations of second-rotation stands in the ESSF zone needs to be addressed urgently.Forestry, Faculty of
Graduate
43
Prather, Hannah Marie. "Examination of Human Impacts on the Biodiversity and Ecology of Lichen and Moss Communities". PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3615.
Texto completoResumen
Globally, more than half of the world's population is living in urban areas and it is well accepted that human activities (e.g. climate warming, pollution, landscape homogenization) pose a multitude of threats to ecosystems. Largely, human-related impacts on biodiversity will hold consequences for larger ecological processes and research looking into human impacts on sensitive epiphytic lichen and moss communities is an emerging area of research. While seemingly small, lichen and moss communities exist on nearly every terrestrial ecosystem on Earth and contribute to whole-system processes (e.g. hydrology, mineral cycling, food web energetics) worldwide. To further examine human impacts on epiphytic communities, I conducted three studies examining urbanization and climate warming effects on epiphytic lichen and moss biodiversity and ecology.
In the first study I revisited a historic urban lichen community study to assess how urban lichen communities have responded to regional air quality changes occurring over the last nearly two decades. I further investigated, for the first time, the biodiversity of urban tree canopy-dwelling lichen communities in a native coniferous tree species, Pseudotsuga menziesii. I found that urban parks and forested areas harbor a species rich community of lichens epiphytes. Further, I found evidence for the distinct homogenization of urban epiphytic lichen communities, suggesting that expanding beyond simplistic measures of biodiversity to consider community composition and functional biodiversity may be necessary when assessing the ecology and potential ecosystem services of epiphyte communites within urbanizing landscapes.
Next, I present the first tall tree canopy study across a regional gradient of urbanization near Portland, Oregon, USA. I found that tall tree canopy epiphyte communities change dramatically along gradients of increasing urbanization, most notably by the transitioning of species functional groups from sensitive, oligotrophic species to a dominance of urban-tolerant, eutrophic species. The implications these dramatic shifts in species composition have on essential PNW ecosystem processes, like N-fixation and canopy microclimate regulation, is still not well understood and is difficult to formally evaluate. However, I find strong evidence that native conifer trees in urban areas may provide a diversity of essential ecosystem services, including providing stratified habitat for epiphyte communities and their associated micro arthropod communities and the scavenging of atmospherically deposited nutrients. Future work is needed to understand how losses in canopy N fixation and species with large biomass (both lichens and bryophytes) will affect nutrient and hydrologic cycling in the PNW region, which continue to undergo rapid growth and urbanization.
The final chapter investigates the impacts of passive warming by Open Top Chambers (OTCs) in moss-dominated ecosystems located on the Western Antarctic Peninsula, an area of increasing climate warming. I compared species-specific temperature effects, moss canopy morphology, sexual reproductive effort and invertebrate communities between OTC and control moss communities for two moss species, Polytrichastrum alpinum and Sanionia uncinata, that make up over 65% of the terrestrial vegetative cover in the area. I found distinct reproductive shifts in P. alpinum under passive warming compared to controls. Moss communities under warming also had substantially larger total invertebrate communities than those in control moss communities, and invertebrate communities were significantly affected by moss species and moss reproductive effort. Further, substantial species-specific thermal differences among contiguous patches of these dominant moss species were revealed. These results suggest that continued warming will differentially impact the reproductive output of Antarctic moss species and is likely to dramatically alter terrestrial ecosystems dynamics from the bottom up.
This combined work provides a diverse contribution to the field of epiphyte ecology and biology by providing new insights on how human impacts will affect epiphyte lichen and moss communities across diverse ecosystems, in light of a rapidly changing planet.
44
Lee, Fung y 李峰. "Climatic change and Chinese population growth dynamics over the last millennium". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39558599.
Texto completo
45
Najafi, Mohammad Reza. "Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes". PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1114.
Texto completoResumen
The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes.
Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes.
Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes.
The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies.
Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS).
46
Redfearn, Howard Daniel. "Rainfall-runoff changes due to urbanization: a comparison of different spatial resolutions for lumped surface water hydrology models using HEC-HMS". Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4939/.
Texto completoResumen
Hydrologic models were used to examine the effects of land cover change on the flow regime of a watershed located in North-Central Texas. Additionally, the effect of spatial resolution was examined by conducting the simulations using sub-watersheds of different sizes to account for the watershed. Using the Army Corps of Engineers, Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS), two different modeling methods were evaluated at the different sub-watershed resolutions for four rainfall events. Calibration results indicate using the smaller spatial resolutions improves the model results. Different scenarios for land cover change were evaluated for all resolutions using both models. As land cover change increased, the amount of flow from the watershed increased.
47
Jablonski, Leanne M. "Reproductive response to elevated CO2 : the roles of vegetative carbon storage, nitrogen and seed traits". Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34646.
Texto completoResumen
This study focused on the reproductive response to elevated CO2 of plants possessing below-ground storage. I tested the hypotheses that under elevated CO2: (1) Plants with greater non-foliar storage capacity win show more reproductive response and (2) The altered foliar physiology of carbon (C) and nitrogen (N) use will cause increases in seed number and quality. Carbon dioxide treatments of High (650 muL L-1) and Ambient (360 muL L-1) were used in a controlled environment, simulated growing season, and in a natural pasture community. Hypothesis 1 was tested experimentally using four Raphanus varieties that differed in hypocotyl and leaf sizes. N fertilization and harvest times were used to obtain a range of root:shoot ratios. Enhancements in vegetative leaf area rather than the hypocotyl predicted reproductive responsiveness to CO 2. However, after three years of CO2 exposure in the pasture, hypocotyl-storing Taraxacum officinale responded strongly in vegetative biomass which correlated with inflorescence size and number. Fitness was enhanced four-fold, while the leaf-storing Plantago major produced more ramets and had only a two-fold fitness increase. Hypothesis 2 was tested by examining the C and N physiology underlying the vegetative organs and seeds of the pasture plants. Under elevated CO2, photosynthesis increased two-fold and senescence was delayed. Total plant C:N ratio did not differ, suggesting N acquisition increased. N similarly limited seed number in all cases suggesting an unchanged Physiology of N use in reproduction. While morphology constrained total biomass response, provisioning to seeds increased as shown by higher seed mass and number and decreased variability in number and mass. In all cases, leaf mass increase under high CO2 corresponded with fitness increase. Phenology constrained response to CO 2 as there was no plasticity in flowering day in Raphanus and Plantago, while there were flowering delays but greater seed maturation rate in Tar
48
Sibanda, Patience. "Climate change mitigation and resilience by four major supermarkets in East London, South Africa". Thesis, University of Fort Hare, 2017. http://hdl.handle.net/10353/5406.
Texto completoResumen
Climate change is a human development challenge. Its negative impacts have the potential to reverse the human development gains made in Africa. South Africa, just like many other countries in the Global South, is being negatively affected by climate change. The country`s economy is largely dependent on agriculture, extractive industries and manufacturing, all of which are vulnerable to climate change in different ways. This vulnerability means different public and private stakeholders must institute sustainable climate change mitigation and adaptation measures so as to ameliorate climate change impacts. Gradually transforming to an environmentally friendly ‘green economy’ and the reduction of greenhouse gas emissions are some of South Africa’s climate change mitigation priorities. Just like the public sector, the private sector has a major role to play in this transition to a low carbon economy through minimising its carbon emissions in their operations. Against this background, this qualitative research examines the role played by four major supermarkets (Shoprite, Spar, Pick n Pay and Woolworths), in climate change mitigation and resilience building. It does so through an appraisal of their mitigation and resilience programs. The four supermarkets were purposively selected in East London, Eastern Cape. Data collection combined heavy reliance on desktop discourse analysis with field interviews in the form of purposively sampled key informant interviews. The results show that the four major supermarkets are implementing a variety of climate change mitigation and resilience strategies. These include reduction of greenhouse gas emissions, prioritisation of renewable energy, recycling and environmentally friendly packaging, promotion of sustainable ways of farming and improved fuel efficiency in their transport systems. In terms of policy improvement, the study recommends that there is need for supermarkets to learn from each other’s’ climate change mitigation initiatives so as to advance South Africa’s ‘green economy’ agenda.
49
Byung, Joo Lee. "Analyse structurale du versant sud de la montagne noire (Hérault - France). Aspects cinématiques de la mise en place des nappes". Phd thesis, Université d'Orléans, 1988. http://tel.archives-ouvertes.fr/tel-00803320.
Texto completoResumen
L'ETUDE DES LINEATIONS D'ALLONGEMENT DES NAPPES-PLIS DE LA MONTAGNE NOIRE PRESENTE DEUX GROUPES D'ORIENTATION DISTINCTS. L'INTENSITE DE LA DEFORMATION AUGMENTE PRES DE LA ZONE AXIOLE. DE NOMBREUX CRITERES DE DEFORMATION NON COAXIALE SONT OBSERVES. LES ROTATIONS INDIQUENT UN CISAILLEMENT SEMESTRE, DANS CERTAINS PLUS LE SENS DE CISAILLEMENT S'INVERSE. LE PLISSEMENT EST SOIT TARDIF, SOIT CONTEMPORAIN DANS UNE DEFORMATION PROGRESSIVE ASSOCIANT UNE CONSTRICTION N-S A UN CISAILLEMENT. DEUX INTERPRETATIONS SONT ALORS POSSIBLE: OU LA LINEATION RESULTE D'UNE REORIENTATION LIEE A UNE SURRECTION OBLIQUE DE LA ZONE AXIALE POSTERIEUREMENT A LA MISE EN PLACE DES NAPPES OU ELLE REFLETE LA DIRECTION ET LE SENS DE TRANSLATION PRIMORDIAUX DES NAPPES
50
Baptista, Vânia Catarina Vieira. "Impacts of environmental changes on bivalves harvesting in Portuguese coast". Dissertação, 2012. https://repositorio-aberto.up.pt/handle/10216/107755.
Texto completo