Дисертації: "Environmental decline"

1

Edwards, Todd A. "Environmental correlates and associations of tuart (Eucalyptus gomphocephala) decline." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2004. https://ro.ecu.edu.au/theses/800.

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Tuart (Eucalyptus gomphocephala DC.) is an ecologically and culturally important tree species that grows across a narrow 400 km long coastal belt, from the Sabrina River south of Perth, to Jurien Bay in the north. Unfortunately, Tuart is also a species under considerable threat due to clearing, lack of recruitment and canopy decline. Canopy decline is of particular concern, being increasingly reported throughout the Tuart distribution. Despite this, previous studies of Tuart have generally been limited to localised canopy decline events. This two-phased study firstly involved an assessment of Tuart canopy condition at 46 sites across the species distribution. At each study site the canopy condition of no Jess than 20 Tuart trees was assessed using estimations of canopy completeness, measures of canopy size reduction, and through the scoring of canopy condition indices. The second phase of the study involved collecting data on a wide selection of environmental factors considered to be important to canopy condition. These included factors of stand structure, understorey composition,landform (soil type, geology, topography, and geography), climate (gradients and change), hydrology (depth, depth change, and chemistry), fire regimes, pollution and anthropogenic disturbance (fragmentation and site disturbance). Assessment of canopy condition indicates that most the Tuart distribution has slight to moderate canopy decline, and is characterised by a mean canopy completeness of 70 percent. Most of this canopy decline is considered to be background (stand level) decline and likely to be a characteristic of the species. However, the lack of comparative studies using similar methodology makes the determination of the current state of Tuart canopy condition difficult. Long-term monitoring of Tuart canopy condition is therefore recommended to determine temporal trends in canopy condition. The main area of concern for Tuart conservation was found to be the Yalgorup region, where trees had typically less than 30 percent canopy completeness. Severe canopy decline in this region is similar to dieback reported in other eucalypt species from across Australia, that is, gradually receding canopy foliage leaving stag-headed trees and abundant epicormic foliage. Localised cases of canopy decline, similar in structure to that of the Yalgorup region, were found at Yellagonga, Neerabup and Ludlow National Park. Investigations into environmental factors found severe canopy decline in the Yalgorup region is associated with higher rainfall, finer and shallower soil, higher groundwater alkalinity and salinity, and greater rates of groundwater salinity increase. Elsewhere Tuart canopy decline was found to be associated with nutrient enrichment (high topsoil ammonium nitrogen) and high levels of fragmentation. Environmental factors other than those mentioned do not appear to be causing Tuart canopy decline across the distribution, for example understorey competition, altered fire regimes and climate change. Future management of Tuart canopy decline needs to focus on the severe canopy decline in the Yalgorup region, and build upon the hypotheses proposed in this study to explain canopy decline. Low recruitment should also not be forgotten as a major cause of the species decline.

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2

Gruber, Holli. "Emotions in Environmental Discourses - Analysing the Insect Decline in Germany." Thesis, Örebro universitet, Institutionen för humaniora, utbildnings- och samhällsvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-67591.

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Insects are not really beloved by many people, although their importance for humankind and the planet’s ecosystem is out of question. The lack of resonance and emotional attachment towards insects have an immense impact on how politics deal with the fact that the number of insects is decreasing and the ecological balance is threatened as a consequence. This thesis contributes to the understanding of the role of emotions in environmental discourses and examines the societal meaning of the insect biodiversity. Analysing how the discourse is visualised and communicated in the media shows how and to what extent different emotions are evoked to make people care about insects, be engaged and mobilised. Emotions can be seen as the base for caring and feeling responsible for the natural word, establishing ecological awareness and inducing socio-political change.

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3

Porcellini, Elisa <1978&gt. "Genetic and environmental factors associated with the risk of cognitive decline and dementia." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3336/.

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AD is the most common age related neurodegenerative disease in the industrialized world. Clinically AD is defined as a progressing decline of cognitive functions. Neuropathologically, AD is characterized by the aggregation of b-amyloid (Ab) peptide in the form of extracellular senile plaques, and hyperphosphorlylated tau protein in the form of intracellular neurofibrillary tangles. These neuropathological hallmarks are often accompanied by abundant microvascular damage and pronounced inflammation of the affected brain regions. In this thesis we investigated several aspects of AD focusing on the genetic aspect. We confirmed that Alpha 1 antichymotrypsin (ACT), an acute phase protein, was associated to AD subjects, being plasma levels higher in AD cases than controls. In addition, in a GWA study we demonstrated that two different gene, Clusterin and CR1 were strongly associated to AD. A single gene association not explain such a complex disease like AD. The goal should be to created a network of genetic, phenotypic and clinical data associated to AD. We used a new algorithm, the ANNs, aimed to map variables and search for connectivity among variables. We found specific variables associated to AD like cholesterol levels, the presence of variation in HMGCR enzyme and the age. Other factors such as the BMI, the amount of HDL and blood folate levels were also associated with AD. Pathogen infections, above all viral infections, have been previously associated to AD. The hypothesis suggests that virus and in particular herpes virus could enter the brain when an individual becomes older, perhaps because of a decline in the immune system. Our new hypothesis is that the presence of SNPs in our GWA gene study results in a genetic signature that might affect individual brain susceptibility to infection by herpes virus family during aging.

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4

Watterson, Patricia A. "Environmental factors in differential infant and child mortality decline in England and Wales, circa 1895 to 1910." Thesis, London School of Hygiene and Tropical Medicine (University of London), 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313117.

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5

Ampudia, Sjogreen Diana Marcela. "“We used to…” The Decline of Social Capital on Providencia Island, Colombia." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471873987.

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6

Roberts, Leri Jane. "Environmental and temporal aspects of bog-pine establishment and decline in central Britain during the Holocene." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266997.

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7

Ostrand, William D. "Disease and Habitat Change as Factors Associated with Mourning Dove Population Decline." DigitalCommons@USU, 1995. https://digitalcommons.usu.edu/etd/6516.

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The western mourning dove (Zenaida macroura) population has been declining since 1966. Data collected in 1951-52, in Fillmore, Utah, provided us a baseline for comparison with our study in the same area. Our approach was to determine whether a local population decline had occurred since the original data were collected, assess if trichomoniasis has impacted the local population, determine if changes in habitat structure affect foraging site selection, quantify changes in habitat, identify which habitats doves preferred, ascertain whether doves had responded to habitat change by changing food habits, and assess if changes in habitat were responsible in part for the local population decline. We found that population counts declined 72% and 82% from 1952 to 1992 and 1993, respectively. We determined that trichomoniasis was not an factor. in the decline. We observed that doves preferred foraging habitat characterized by a short and open structure and will not forage in the taller, denser vegetation that now dominates the study area. The most dramatic change in habitat was an 82% decline of land in winter wheat production. In 1951-52 and 1992-93, doves consumed wheat in greater frequency and volume than any other food item. Habitats selected for foraging were wheat fields following harvest, feedpens, hay storage yards, and weedy patches. Of these habitats, area in wheat fields and number of feedpens had changed extensively. The decline in wheat availability, either at harvested fields or feedpens, appears to have contributed to the local population decline. We used regression analysis to test the statewide relationship between the decline in the mourning dove population index, area in winter wheat production, and the number of farms with cattle and obtained significant results (R2 = .42, P = 0.001).

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8

Sinnott, Tyler King. "Eelgrass (Zostera marina) Population Decline in Morro Bay, CA: A Meta-analysis of Herbicide Application in San Luis Obispo County and Morro Bay Watershed." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2236.

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The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis Obispo (SLO) County and Morro Bay Watershed by analyzing data of application by mass, area, and intensity to identify herbicides with the highest potential for local environmental pollution. California Pesticide Use Annual Summary Reports (PUASR) from the years 2000 to 2017 were used to obtain data for conducting a meta-analysis to estimate total herbicide application by weight within every township, range, and section for each of the eight selected herbicides: oxyfluorfen, glyphosate, diuron, chlorthal-dimethyl, simazine, napropamide, trifluralin, and oryzalin. A second goal was to select an analytical laboratory that would be best suited for herbicide analysis of estuary sediments to determine the presence, or lack thereof, of the eight selected herbicides. Criteria of consideration in laboratory selection included herbicides detection capabilities, detection/reporting limits, testing prices, chain of custody protocols, turnaround times, and laboratory site locations. The meta-analysis yielded results showing high herbicide application rates in SLO County with glyphosate, oxyfluorfen, and chlorthal-dimethyl being identified as three herbicides of elevated risk for local environmental contamination due high rates of use by mass, by area, and/or intensity during the study timeframe. Additionally, Morro Bay Watershed exhibited moderate rates of herbicide application with chlorthal-dimethyl and glyphosate being of highest risk for contamination and accumulation within the estuary because of high application rates by mass, by area, and/or intensity. Finally, Environmental Micro Analysis (EMA) and Primus Group, Inc. (PrimusLabs) were identified as the top candidates for analytical laboratory testing of Morro Bay Estuary sediment samples to be obtained and tested for the selected herbicides. These laboratories provide superior analytical capabilities of the eight herbicides, impressive reporting limits or lower detection limits, competitive testing prices for detecting multiple constituents in multiple samples, robust chain of custody protocols, options for quick turnaround times, and laboratory site locations within California.

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9

Wilson, Victoria R. "Point Pleasant Produced Water Characterization: An Analysis of Past Production and Prediction of Future Production." Youngstown State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu155973360664964.

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10

Brown, Jenise. "Net Effects of Batrachochytrium dendrobatidis (Bd) and Fungicides on Anurans Across Life Stages." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4643.

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Amphibians are declining at alarming rates globally. Multiple factors contribute to these declines, including chemical contaminants and emergent diseases. In recent years, agrochemical use, especially fungicide applications, has increased considerably. Previous studies have demonstrated that these agrochemicals leave application sites and enter wetlands via runoff and have detrimental effects on non-target organisms. For example, exposure to contaminants can have multifarious effects on amphibians, such as reducing their ability to deal with a secondary stressor, such as disease. A pathogen that is found concomitant with chemical contaminants in aquatic systems is Batrachochytrium dendrobatidis (Bd). Bd has decimated amphibian populations worldwide. Susceptibility to this pathogen varies across amphibian life stages, and is greater in adults than larvae. Consequently, it is important to examine the effects of simultaneous and serial Bd and agrochemical exposure throughout amphibian development. I assessed the combined effects of 3 different fungicides and Bd on two amphibian species: Cuban tree frogs (Osteopilus septentrionalis) and grey tree frogs (Hyla versicolor), both simultaneously and across life stages. To elucidate the complexities of these interactions, I conducted two experiments, one in the laboratory and another in outdoor mesocosms. Frogs were exposed to most of the possible combinations of fungicides and Bd as tadpoles and metamorphs. The presence of fungicides during the tadpole stage caused no difference in timing to metamorphosis and therefore no extension of time animals were exposed to the pathogen. Fungicides did not reduce fungal growth; in fact, tadpoles exposed simultaneously to a fungicide and Bd, regardless of the specific fungicide, had increased fungal loads compared to acetone controls. Additionally, animals exposed to both stressors simultaneously had higher mortality compared to controls or any of the stressors singly. Lastly, the fungicide had persistent effects on amphibian health by affecting susceptibility to Bd later in ontogeny. Frogs exposed to any of the three fungicides as a tadpole had higher Bd prevalence, Bd abundance, and Bd-induced mortality when challenged with Bd after metamorphosis, an average of 71 days after their last fungicide exposure. In conclusion, I found no benefits of fungicides for amphibians. In fact, results indicate both immediate and delayed negative effects of exposure to fungicides and Bd. These findings highlight the importance of studying multiple potential contributors to amphibian declines, simultaneously and sequentially, to understand net effects of stressors on amphibian performance.

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11

Leopold, Susan Rene. "Dormant Ethnobotany: A Case Study of Decline in Regional Plant Knowledge in the Bull Run Mountains of Virginia." Antioch University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1301582669.

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12

Evans, David M. "A Spatiotemporal Analysis of Aspen Decline in Southern Utah’s Cedar Mountain, Using Remote Sensing and Geographic Information Systems." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/734.

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Widespread mortality of quaking aspen (Populus tremuloides Michx.) has occurred over large expanses of the Western US during the 20th century. While much of this decline was due to conifer encroachment into seral aspen, significant aspen losses also occurred in areas of persistent aspen and may have been exasperated by drought conditions. Aspen decline has been especially notable at Cedar Mountain, Utah, an area of mostly private land and extensive persistent aspen coverage. The objectives of this study were to create a time series of live and dead aspen cover on the Cedar Mountain landscape, using remotely sensed imagery, and to test whether water stress correlated to the decline therein. To accomplish these objectives, a decision tree classifier was used to classify the Cedar Mountain area into live and dead aspen cover classes for the years 1985, 1990, 1995, 2001, 2005, and 2008. Thereafter, post-classification change analysis was performed to determine areas and time periods of elevated decline. Regression analyses were performed to ascertain correlations between climatic data and percent change in aspen cover. A topographic analysis using zonal statistics was also performed to determine landscape positions where aspen decline is more prevalent. The time series models indicated that aspen decline followed a step-wise pattern with an overall decrease of 23.57 % in aspen cover during a 23-year period. Considerable aspen decline occurred early in the study time frame, with decreases of 1.38 and 1.36 -1 in 1990 and 1995, respectively. The middle period between 1995 and 2001 had no net change in aspen cover. However, the end of the time series showed the greatest decline with decreases of 1.56 and 1.99 % yr-1 in 2005 and 2008, respectively. There was a correlation between percent change in aspen cover and precipitation, suggesting that drought weakens aspen, making it susceptible to future decline. The topographic zonal statistics revealed that drier landscape positions had greater frequencies of dead aspen. The most significant predictor of aspen decline was elevation, which was significantly greater in the live aspen for three of the five years.

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13

Andersson, Marie. "Oak (Quercus robur L.) mortality in south-eastern Sweden: influence of weather and environmental variables." Thesis, Linköpings universitet, Ekologi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19278.

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The complex interplay between biotic and abiotic factors, believed to be responsible for several oak declines in European oak stands during the last three decades, remains poorly understood. Hence, this study aims at clarifying the temporal process of oak declines, as well as identifying individual tree and environmental variables that increase the risk of oak mortality. The study was performed in one of the few areas in northern Europe still holding high densities of old oaks (Quercus robur L.). Cross dating revealed that most trees had died during the last decade. Averaged chronologies and multiple chronological clustering suggested that the onset of the oak decline happened in 1992, when a severe drought took place. Two of the sites showed a rather short time period of heavily reduced growth prior to death, most likely caused by an insect defoliation in combination with a mildew infection of the replacement shoots. Environmental variables presented a rather weak influence on oak mortality. The results support the idea of attributing oak mortality to a combination of long- and short-term stresses, and emphasize the importance of including present as well as past factors when analysing the causes of oak declines.

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14

Kroloff, Emily K. N. "Where Are All the Bonefish? Using Angler Perceptions to Estimate Trends of Bonefish (Albula vulpes) Decline in South Florida." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2541.

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Local ecological knowledge (LEK) is a useful method to capture environmental or resource changes when there is an absence of biological data. Since the bonefish fishery is data limited, this study aims to understand the trend of bonefish decline over the last 40 years using LEK and to assess whether varying fisher experience and fisher type would influence perception of bonefish decline. Semi-structured surveys and key informant interviews were conducted to collect LEK data. Along with perceiving an overall decline (p

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15

Skinner, Aaron. "Using GPS-Tracking to Fill Knowledge Gaps in the Full Annual Cycle of an Elusive Aerial Insectivore in Steep Decline." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1626886599137179.

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16

Mohaghegh, Motlagh Seyed Amir H. "An Investigation into the Impact of Cell Metabolic Activity on Biofilm Formation and Flux Decline during Cross-flow Filtration of Cellulose Acetate Ultrafiltration Membranes." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1310138074.

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17

Ladd, Shannon. "A Retrospective Analysis of the Potential Environmental Stressors Responsible for the Decline of the Natural Populations of the Florida Apple Snail (Pomacea paludosa) in the A.R.M. Loxahatchee National Wildlife Refuge." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3642.

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The purpose of this thesis is to determine the factors that contributed to the decline of Florida apple snail ( Pomacea paludosa) populations in the A.R.M. Loxahatchee National Wildlife Refuge with the goal of devising management recommendations to the Refuge regarding population management strategies. The factors examined that could have potentially contributed to population decline include the use of copper-based herbicides, insecticide application, the occurrence of drought, the use of other herbicides, the occurrence of fire, and non-avian predation. Annual Narrative documents produced by Refuge managers and staff members, dated from 1951 to 2007, were used to collect historical data for these factors. The quality of data reporting within the Annual Narratives was also examined. To support data on droughts documented in the Annual Narratives, surface water and rainfall data were obtained and analyzed. The methodology includes the use of conceptual ecological models and historical ecology to determine whether or not the factors examined produced an ecological effect capable of affecting the Refuge population of apple snails. Evidence from the Annual Narratives suggests that the use of copper-based herbicides, the occurrence of drought, and predation by alligators were responsible for the decline of the apple snail on the Refuge. A lack of consistently reported data regarding apple snail densities makes it difficult to determine the degree to which each factor had an effect on the apple snails or to determine if any spatio-temporal relationship existed between the Florida apple snail and Everglade snail kite ( Rostrhamus sociabilis plumbeus) based on copper-based herbicide use. The overall quality of the Annual Narratives improved throughout the study period and eventually focused heavily on investigative studies. Several management recommendations were suggested to improve Florida apple snail populations on the Refuge. First, in order to monitor the health and trends of the apple snail population, a monitoring network needs to be established with results maintained in a geodatabase. Both apple snail density and egg cluster counts need to be made following an established sampling method. Second, in an attempt to sustain higher apple snail densities, stocking of the interior should be attempted. Finall, in the event that adjacent farmlands are to be restored, soil samples need to be analyzed to determine if concentrations are high enough that desorption of copper from the flooded agricultural soils could pose a serious threat to the Refuge by reintroducing toxic levels of copper.

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18

Du, Plessis Jacobus Johannes. "Die invloed van plattelandse toerisme op die ontwikkeling en struktuur van Sutherland." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/4031.

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Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2009.
This study combines qualitative and quantitative techniques in an inquiry into the influence of rural tourism on the development and structure of Sutherland from 2001 till 2005. Sutherland, like most small rural towns in the Central and Western Karoo, is/was in the process of decline. Rural tourism is seen as a solution to curb the process of decline. The study investigates this assumption by analyzing the positive and negative impacts of tourism on the economic, social and environmental spheres of Sutherland and looks at concomitant structural changes. Special emphasis is placed on the changing nature of Sutherland’s reason for existence and the dualistic processes of degradation on the one side and tourism development on the other. These complex time-spatial and site-specific trends are analyzed and recommendations are made for the management of the tourism industry of Sutherland.

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19

Dekking, Anoek. "Phase Out the Old to Phase In the New: Managing the Heat Transition in Leiden, the Netherlands." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-444620.

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By 2050, the Netherlands wants to reduce its use of natural gas for heating to zero. Currently, over 90%of houses are dependent on the fossil resource to warm their houses. As such, the phase-out of natural gas hasbecome an important policy project. The government delegated the formulation of the phase-out strategy andexecution to the 347 municipalities. This thesis examines how one municipality, Leiden, has formulated andimplemented this strategy. In doing so, the thesis addresses two matters in the literature on energy transitionswhich have received little attention: heating and deliberate decline. Traditionally, the focus within this field hasbeen on electricity and innovation. This thesis aims to find out to what extent the Transition Management (TM)framework by Derk Loorbach (2010) can be applied as a guide to a phase-out policy formulation process of theWarmtevisie of the Dutch municipality of Leiden. The thesis uses the process tracing methodology to combinedata generated from document analysis and two interviews with policy makers involved in the policy formulationprocess. By comparing the process followed in Leiden with the analytical framework of TM, the thesis shows thatthe TM framework could be used to guide to the phase-out policy formulation process to a large extent. However,the case study also shows that knowledge and expertise must increase substantially for a sound strategy to emerge.Additionally, it shows that even within phase-out strategies the focus remains on innovation practises.

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Sjölinder, Marie. "Age-related cognitive decline and navigation in electronic environments." Doctoral thesis, Stockholm University, Department of Psychology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1038.

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The older population is increasing, as is life expectancy. Technical devices are becoming more widespread and used for many everyday tasks. Knowledge about new technology is important to remain as an active and independent part of the society. However, if an old user group should have equal access to this technology, new demands will be placed on the design of interfaces and devices. With respect to old users it is and will be important to develop technical devices and interfaces that take the age-related decline in physical and cognitive abilities into account. The aim of this work was to investigate to what extent the age-related cognitive decline affects performance on different computer-related tasks and the use of different interfaces. With respect to the use of computer interfaces, two studies were conducted. In the first study, the information was presented with a hierarchical structure. In the second study the information was presented as a 3D-environment, and it was also investigated how an overview map could support navigation. The third study examined the age-related cognitive decline in the use of a small mobile phone display with a hierarchical information structure. The results from the studies showed that the most pronounced age-related difference was found in the use of the 3D-environment. Within this environment, prior experience was found to have the largest impact on performance. Regarding the hierarchical information structures, prior experience seemed to have a larger impact on performance of easy tasks, while age and cognitive abilities had a larger impact on performance of more complex tasks. With respect to navigation aids, the overview map in the 3D-environment did not reduce the age-differences; however, it contributed to a better perceived orientation and reduced the feeling of being lost.

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Sjölinder, Marie. "Age-related cognitive decline and navigation in electronic environments /." Stockholm : Department of Psychology, Stockholm University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1038.

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22

Graziano, Michael Paul. "The Role of Forest Composition on Pool-breeding Amphibians: Colonization, Larval Communities, and Connectivity." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492685290070103.

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23

Tibbits, Matthew A. Budd Ann F. "The effects of decling environmental pH on coral microstructure and morphology." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/445.

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Tibbits, Matthew A. "The effects of decling environmental pH on coral microstructure and morphology." Thesis, University of Iowa, 2009. https://ir.uiowa.edu/etd/445.

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Coral reefs are faced and will be faced with many challenges this century. One danger is the rapid decline of oceanic pH due to anthropogenic sources. The more acidic the environment becomes, the harder reefs and coral (order: scleractinia) in particular will be hit. Experiments to measure the effect on scleractinian coral were performed to glean a better understanding of the processes that will be affected by our acidifying oceans. Additionally, the search for and analysis of coral microstructure and micromorpholgy were carried out in an attempt to understand homology within an environmentally responsive taxa.

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Proffitt, Fiona M. "Causes of population decline of the bullfinch Pyrrhula pyrrhula in agricultural environments." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270646.

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Krynak, Katherine L. "ENVIRONMENTAL INFLUENCES ONAMPHIBIAN INNATE IMMUNE DEFENSE TRAITS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1435590530.

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27

Beecher, Nancy A. "Frog declines exploring connections among climate change, immunity and disease /." [Bloomington, Ind.] : Indiana University, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3243772.

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Thesis (Ph.D.)--Indiana University, Dept. of Biology, 2006.
Title from PDF t.p. (viewed Nov. 18, 2008). Source: Dissertation Abstracts International, Volume: 67-12, Section: B, page: 6837. Advisers: Greg E. Demas; Craig Nelson.

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Rider, David Anthony. "The inflammatory environment and the decline of T lymphocyte activation signalling and function in rheumatoid arthritis." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274363.

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29

Hively, Angela H. "Sealift transportation in a working capital fund environment : rate stability when workload declines." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA362719.

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Thesis (M.S. in Management) Naval Postgraduate School, March 1999.
Thesis advisor(s): Ira A. Lewis, Theodore A. Hleba. "March 1999". Includes bibliographical references (p. 49-50). Also available online.

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30

Perkins, Allan John. "Causes of decline and conservation solutions for Corn Buntings Emberiza calandra in eastern Scotland." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7764.

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The Corn Bunting Emberiza calandra is one of the most severely declining farmland birds across Europe. In the UK, numbers fell by 86% between 1967 and 2008. Corn Buntings favour open landscapes, nest on or close to the ground, are often polygynous, double-brooded, and have a seed-based diet supplemented in summer by invertebrates. This study investigated the recent causes of decline in arable and mixed farmland in eastern Scotland, and sought to identify potential conservation solutions that could be delivered through agri-environment schemes (AES). Combining new data with analyses of existing long-term datasets, I investigated habitat associations during summer and winter, the timing and success of nesting attempts, and measured reproductive and population responses to AES. Corn Buntings declined almost to extinction in one study area where, over 20 years, the main recorded intensifications of farming were reduced weed abundance within crops and removal of boundaries to make bigger fields. Territory locations, late-summer occupancy and polygyny were all strongly associated with weedy fields. There were also positive associations with overhead wires and in early summer with winter barley and forage grasses. Late-summer occupancy was associated with spring-sown cereals, crops that are amongst the last to be harvested. Changes in habitat associations and to aspects of the mating system as the population declined and agriculture intensified are discussed. Intensive monitoring showed that Corn Buntings laid clutches from mid-May to mid-August, mostly in fields of forage grasses and autumn-sown cereals in early summer, and spring sown cereals in late summer. A preference for nesting in dense swards explained this seasonal variation. Breeding success in forage grasses was poor, due to high rates of nest loss during mowing. However, in experimental trials, nest success in fields with delayed mowing was fivefold that of control fields. With sufficient uptake through AES, delayed mowing could raise productivity to levels required to reverse population declines. In winter, cereal stubbles and AES unharvested crop patches were the main foraging habitats used. Unharvested crops with abundant cereal grain in their first winter of establishment were favoured. Population monitoring over seven years and 71 farms revealed increases on farms with AES targeted at Corn Buntings, no significant change on farms with general AES, and declines on control farms. In arable-dominated farmland, management that increased food availability reversed declines, but on mixed farmland where Corn Buntings nested in forage grasses, delayed mowing was essential for population increase. This study has already influenced the design of AES targeted at Corn Buntings in Scotland, and I make further recommendations for the species’ conservation and design of AES that are applicable to farmland throughout Britain and Europe.

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31

Cognat, Mathis. "Rôles des facteurs environnementaux et des interactions biomorphodynamiques sur l’évolution spatio-temporelle des herbiers de zostères dans une lagune mésotidale." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0170.

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Les phanérogames marines constituent un compartiment biologique fondamental et fournissent de nombreux services écosystémiques. Comprendre leur évolution et les interactions avec leur environnement physique est un enjeu scientifique majeur à l’échelle mondiale. Dans le bassin d’Arcachon, des herbiers de Zostera noltei (le plus grand d’Europe) et de Zostera marina ont vu leur surfaces régresser fortement ces deux dernières décennies. La régression s’est accompagnée d’une augmentation des concentrations en sédiments en suspension et de modifications morphologiques significatives. Dans ce contexte, et à travers cet exemple régional, les objectifs de la thèse sont de mieux comprendre les causes physiques de la régression des herbiers de zostères et de démêler et de quantifier les conséquences physiques de la régression et les effets de rétrocontrôle.Un monitoring exhaustif des herbiers (suivi des paramètres biologiques, chimiques et physiques sur neuf sites durant une année) a montré d’une part l’extrême variabilité des conditions environnementales auxquelles sont soumis les herbiers de zostères naines du Bassin et d’autre part d’importantes différences démographiques, morphologiques et biochimiques entre les plantes des différents sites. Certaines de ces différences reflètent leur capacité d’adaptation à l’intensité d’un forçage. Un modèle logistique croissance a montré qu’outre la lumière, les paramètres principaux qui contrôlent le développement de Z. noltei à l’échelle du Bassin sont les forçages hydrodynamiques. Toutefois à l’échelle locale, d’autres facteurs tels que la teneur en matière organique ou la microtopographie s’avèrent prépondérants.Dans un second temps, une analyse associant des données historiques et des scénarios de modélisation hydrodynamique a montré que la profondeur maximale colonisée par les deux espèces de zostères avait fortement diminué entre 1989 et 2016, suggérant un effet du manque de lumière sur l’évolution de la distribution des deux espèces. Par ailleurs, il s’est avéré que la régression des zostères naines avait débuté au niveau des zones les plus pentues des estrans, qui correspondent aux rebords des chenaux et sont donc soumises aux courants les plus intenses, suggérant là encore un effet de l’intensité des courants sur la distribution de Z. noltei.Les résultats des simulations numériques ont montré que la régression des deux espèces induit une augmentation importante de l’énergie hydrodynamique, non seulement localement dans les zones où les herbiers ont régressé, mais également à distance, au niveau des chenaux principaux et jusqu’à près de l’embouchure.De plus, les effets hydrodynamiques induits par la régression initiale de Z. marina (1989-2007) ont contribué à la première phase du déclin des herbiers de Z. noltei. Ces résultats confirment en partie l’hypothèse que des processus de rétrocontrôle entre hydrodynamique et régression des herbiers de zostères sont intervenus au cours de la première phase du déclin des zostères. Par ailleurs, les conséquences hydrodynamiques directes de la première phase de régression des deux espèces (1989-2007) expliquent plus de 75 % de la seconde phase de régression de Z. noltei (2007-2012). Ces résultats confirment pleinement l’existence des processus de rétrocontrôle et met en évidence leur rôle prépondérant sur la dynamique des herbiers de Z. noltei.En ce qui concerne Z. marina, il apparaît enfin que les conditions actuelles ne permettent pas sa reconquête des zones d’où elle a disparu. Au contraire, du fait de sa position intertidale la rendant moins sensible aux fortes turbidités, Z. noltei pourrait recoloniser un certain nombre d’estrans qui leur sont favorables sur le plan hydrodynamique. Ce processus de recolonisation, conduisant à une réduction de l’énergie hydrodynamique et à l’amélioration locale des conditions lumineuses, pourrait s’auto-amplifier de proche en proche et favoriser la reprise de Z. marina dans les chenaux
Seagrass meadows are a fundamental biological component and provide many ecosystem services in coastal areas. Understanding their evolution and interactions with their physical environment is a major scientific issue. In Arcachon Bay, seagrass meadows of Zostera notlei (the largest in Europe) and Zostera marina have sharply regressed over the last two decades. In the meantime, an increase in suspended sediment concentrations and significant morphological changes were observed. Based on this regional case study, the objectives of this thesis are to better underestand the physical causes of seagrass bed regression, and also to quantify the physical consequences of the egression and possible feedback processes.An extensive monitoring of biological, chemical and physical parameters at nine sites during one year showed the extreme variability of the environmental conditions to which the Z. noltei beds are subject in Arcachon Bay, the important demographic, morphological and biochemical differences between plants of different sites. Some of these differences reflect their ability to adapt to the intensity of a forcing. A logistic growth model has shown that in addition to light, the main parameters that control the development of Z. noltei at the scale of the bay are hydrodynamic forcing. However, at the local scale, other factors such as organic matter content or microtopography may be predominant.In a second step, an analysis combining historical data and hydrodynamic modelling scenarios showed that the maximum depth colonized by the two species of seagrass strongly declined between 1989 and 2016. This analysis suggests that lack of light had an effect on the evolution of the distribution of the two species. In addition, it was found that the regression of Z. noltei began on the steepest areas of the tidal flat, which correspond to the edges of the channels and were therefore subject to the most intense currents, suggesting again an effect of intensity of currents on the distribution of Z. noltei.The results of numerical simulations showed that the regression of both species induces a significant increase in hydrodynamic energy, not only locally in areas where the seagrass have declined, but also remotely, at the level of main channels and up to near the mouth.In addition, the hydrodynamic effects induced by the initial regression of Z. Marina (1989-2007) contributed to the first phase of the decline of Z. noltei meadows. These results partially confirm the hypothesis that feedback processes between hydrodynamics and regression of seagrass beds occurred during the first stage of seagrass decline. Furthermore, the direct hydrodynamic consequences of the first regression phase of the two species (1989-2007) accounted for more than 75% of the second regression phase of Z. noltei (2007-2012). These results fully confirm the existence of feedback processes and highlight their predominant role in the dynamics of Z. noltei meadows.As far as Z. marina is concerned, it finally appears that the current conditions do not allow colonization of the areas from which it disappeared. On the contrary, due to its intertidal position making it less susceptible to high turbidity, Z. noltei could recolonize some tidal flats that present favourable hydrodynamic conditions. This process of recolonization, leading to a reduction of the hydrodynamic energy and to the local improvement of the light conditions, could self-amplify by adjaceting to each other and then promote the recovery of Z. marina in the channels

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Christensen, Peter Sampson Steven. "The decline of Iranshahr : irrigation and environments in the history of the Middle East, 500 B.C. to A.D. 1500 /." Copenhagen : Museum Tusculanum press, University of Copenhagen, 1993. http://catalogue.bnf.fr/ark:/12148/cb376666790.

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33

Penner, Johannes. "Macroecology of West African amphibians." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2014. http://dx.doi.org/10.18452/17035.

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Amphibienpopulationen sind weltweit bedroht. Für fundierte Entscheidungen im Naturschutz ist ein wissenschaftliches Hintergrundwissen notwendig. Eine wichtige Komponente ist die Verbreitung der Arten und die Gründe hierfür. Dies setzt auch Klarheit bezüglich des taxonomischen Status voraus. Vernachlässigte Regionen liegen meist in den Tropen. Um diese Lücke zu füllen, untersucht die vorliegende Arbeit die Makroökologie westafrikanischer Amphibien. Eine neue Art der Familie Phrynobatrachidae wird beschrieben. Anschließend werden die taxonomischen Unterschiede zweier Mitglieder der Familien der Hyperoliidae und der Arthroleptidae untersucht. Dies ebnet den Weg für die Makroökologie. Es wird analysiert, ob Westafrika eine einzigartige biogeographische Region ist. Die Untersuchung zeigen, dass Westafrika in der Tat einzigartig ist. Die Ähnlichkeiten innerhalb der Region sind größer als die innerhalb ähnlicher Habitate aus unterschiedlichen Regionen. Der Cross River ist die wichtigste Barriere. Mehrere geographische Zonierungen innerhalb Westafrikas werden entdeckt. Es wird untersucht, ob der Chytrid Pilz, Batrachochytrium dendrobatidis, (Bd), ein wichtiger Faktor beim Rückgang der Amphibien Populationen, in West Afrika vorkommt. Bisher gibt es keinen positiven Nachweis westlich Nigerias. Dennoch sagen Modelle geeignete Habitate für Bd vorher. Die wahrscheinlichste Erklärung ist, dass die Dahomey Gap als natürliche Barriere die Ausbreitung von Bd verhindert. Als letztes werden die Nischen westafrikanischer Amphibien eruiert. Für die meisten Arten werden Nischenmodelle berechnet. Dies bestätigt bereits bekannte Gebiete hoher Alpha Diversität und zeigt bisher unbekannte Gebiete auf. Des Weiteren werden Erklärungen für unterschiedliche Verbreitungsgebietsgrößen gesucht. Generell wird die Nischenbreite hierfür verantwortlich gemacht. Die vorliegenden Daten lassen allerdings auch den Schluss zu, dass das Ausbreitungsvermögen das beobachtete Muster ebenfalls erklären kann.
Amphibian populations are declining globally. For informed conservation decisions a sound scientific background is needed. One major component is species distribution and the underlying causes. This also requires clarity on the taxonomic status. Often neglected regions are located in the tropics. In order to fill this gap, the present thesis examines the macroecology of West African amphibians. A new species of the family Phrynobatrachidae is described. Afterwards, the taxonomic differences between morphologically similar members of the families Hyperoliidae and Arthroleptidae are discussed. Beside other studies, this sets the field for macroecology. It is tested whether West Africa is a unique biogeographic region. The similarity of amphibian assemblages from Sub-Saharan Africa is analysed and it is shown that West Africa contains unique assemblages. Similarities within the region are higher than similarities between habitats across different regions. The main barrier towards Central Africa is the Cross River. Several geographic divisions within West Africa are detected. It is examined whether the chytrid fungus Batrachochytrium dendrobatidis (Bd), one important factor for amphibian population declines in many other regions, occurs in West Africa. So far there is no positive record west of Nigeria. However, models predict that environmental suitability for Bd is high. The most plausible explanation for the absence is that the Dahomey Gap acted as a natural barrier against the spread of the Bd. Finally, the niches of West African amphibians are investigated. For most species environmental niche models are calculated. This confirms previously known areas of high alpha diversity and so far unknown species rich areas are detected. In a further study, explanations for differing range sizes are searched for. Niche breadth is commonly assumed to be the general cause. However, the analysed data also suggests that dispersal ability can also explain the observed pattern.

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Allison, Isaiah. "Techno-economic evaluation of associated gas usage for gas turbine power generation in the presence of degradation & resource decline." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/9233.

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This research examined the technical and economic feasibility of harnessing flare gas emissions from oil fields. The outcome would provide the basis for a substantial re-utilization of this waste energy due to the current practice of flaring and use it alternatively as energy for powering oil fields, rural electrification and desalination. Nigeria is used as a case study. Burning fossil fuels have grave environmental impact, amidst increasing global concerns over harmful emissions. This research addresses resource decline and suggests divestment as a partial cure. The gas turbine is subject to degradation of its components as it is used. Though several methods of assessing gas turbine degradation have been developed with varying degrees of success, no one method has addressed issues pertaining to associated gas and its effects on degradation with divestment. Simulation of two single shaft, heavy duty industrial gas turbines; and three aero-derivative industrial gas turbines of the heavy medium and light capacity ranges were carried out for varying operating conditions, to ascertain the effects of degradation when run on associated gas. Thereafter, optimizations for the best power plant engine mix and the least cost of electricity were carried out. Genetic algorithm was used to assess a population of 10,000 individuals over 500 generations; convergence was achieved for different configurations of the five study engines at discount rates of 5% and 10%, over three power ranges. The divestment pattern starts with the lightest aero-derivative industrial gas turbine; the best power plant selection was limited to the two lightest aero-derivatives in the fleet, completely ignoring the heavy engines. A techno-economic, environmental and risk assessment model comprising performance, emission, economics and risk modules was successfully developed to assess gas turbine degradation with divestment. Using this tool, it was confirmed that associated gas usage resulted in degradation of gas turbine performance, an increase in gas collection as well as operation and maintenance costs. Also there was increasingly higher creep life consumption during slow, medium and fast degradation scenarios for both engine sets. The novel technical contribution of the research work therefore is the influence of degradation on the economic use of associated gas as fuel in gas turbine power generation; and the implementation of divestment in the face of fuel decline.

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Harring-Harris, Kaarissa. "Preventing bird declines in urban landscapes: Influence of behavioural traits and streetscape plantings." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2022. https://ro.ecu.edu.au/theses/2538.

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Urbanisation is thought to be the leading cause of habitat loss and ecosystem fragmentation world-wide. Australian urban bird communities are constantly under threat from landscape modification and the associated disturbances. The Perth metropolitan region, Western Australia provides a unique case study to observe the impact of a developing city that is also located in a biodiversity hotspot. The long-term reporting rate of 66 small passerine birds was analysed on a time and spatial scale, utilising 20 years of citizen science from Birdata collected by birdwatchers. The study compared the overall change in reporting rate to changes in the urban environment, focusing on human population density and the canopy cover of native trees. Life history traits were also used to determine if certain groups/guilds of birds responded differently to changes in the urban landscape. This study revealed that a concerning number of urban sensitive native species are in decline and are being replaced by native and exotic ‘urban-exploiters’. Species that were found to be most at risk in this study were foraging specialists, particularly insectivores, small understorey-dependent birds, and species reliant on large bushland remnants. The study also found generalist species and large nectarivorous birds are increasingly dominating the urban community. Australian urban gardens and streets are lined with nectar-rich, seed-producing vegetation both native and exotic; therefore, favouring species that have the ability to exploit novel foraging resources. Significant loss of habitat in lower strata levels, as a result of land clearing, has reduced the connectivity between large bushland remnants. This has led to urban bird communities becoming overrun by species that frequently utilise the upper canopy and/or thrive in open green areas. Many endemic and native species are locally threatened, and by identifying ‘at risk’ species we can better understand the association between environmental and ecological factors and the impact they have on an individual’s urban tolerance.

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Hautier, Louis. "Intraguild predation in Harmonia axyridis and its effects on native coccinellids." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209619.

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During the 1990s, over a period of just a few years, the multi-colored Asian lady beetle, Harmonia axyridis (Pallas) invaded the entire area of northern Europe. In parallel with this invasion, a decline in native coccinellid species was recorded in Belgium, Britain, and Switzerland, affecting mainly one common species: the two-spot ladybird, Adalia bipunctata L. An impressive trait of H. axyridis, that could explain both its high invasiveness and the decline of native coccinellids, is its predation behaviour. Intraguild predation is a trophic interaction between species that share the same prey – in this case, aphids. In order to determine the precise impact of this predation on the native coccinellid species, the predation behaviour of H. axyridis larvae was observed in Petri dishes and on plants. The resistance of H. axyridis to predation was also studied by exposing it without dorsal spines to native predator larvae, in order to test whether or not the dorsal spines are a physical defence against intraguild predation. In addition to these laboratory experiments, an original method was developed and used to track predation under field conditions. This method is based on the gas chromatography–mass spectrometry (GC-MS) detection of exogenous alkaloids in H. axyridis, especially alkaloids from native coccinellids likely to be subject to intraguild predation. My results show that, in the absence of aphids, H. axyridis consumes both A. bipunctata eggs and all larval instars in Petri dishes. On plants, depending to aphid density, this interaction can change with regards to larvae but not eggs. In addition to intraguild predation, competitive exclusion can occur because of quite aggressive behaviour towards competitors. Dorsal spines significantly reduce the number of bites inflicted, and thereby complement the other defense mechanisms of H. axyridis that enable it to remain dominant in competition for food resources. In semi-natural conditions, predation on the native coccinellids Adalia spp. Calvia spp. Coccinella septempunctata L. and Propylea quatuordecimpunctata (L.) was detected. The number of sites where this predation was observed suggests that this interaction is frequent. It was also observed that an H. axyridis larva can ingest several native coccinellid species, confirming its status as a predator of coccinellids. We can therefore conclude that intraguild predation by H. axyridis leads, as does resource competition, to a decline in native coccinellids./Introduite pour la lutte biologique dans les années 90, la Coccinelle asiatique, Harmonia axyridis (Pallas), a envahi en quelques années toute l’Europe du Nord. Parallèlement à cette invasion, un déclin de plusieurs espèces de coccinelles indigènes dont la très commune Coccinelle à deux points, Adalia bipunctata L. a été observé dans différents biotopes en Belgique, en Angleterre ainsi qu’en Suisse. Un des traits remarquables de la Coccinelle asiatique est son comportement de prédateur intraguilde qui pourrait expliquer à la fois ce déclin mais aussi en partie son caractère hautement invasif. La prédation intraguilde est une interaction trophique entre des espèces qui se nourrissent d’une même proie, dans ce cas-ci les pucerons. Afin de mieux connaître l’impact de cette prédation sur les coccinelles indigènes, le comportement de prédation des larves d’H. axyridis a été décrit en boîtes de Petri et sur plantes. Sa résistance à la prédation a également été étudiée en exposant des larves dépourvues d’épines dorsales à un prédateur indigène, dans le but de tester le rôle de ces épines en tant que défense physique à l’égard d’un prédateur intraguilde. En plus de ces expériences de laboratoire, une méthode originale a été développée et utilisée pour suivre cette prédation en conditions semi-naturelles. Elle se base sur la détection, en GC-MS, des alcaloïdes exogènes chez H. axyridis et en particulier des alcaloïdes produits par d'autres espèces de coccinelles susceptibles de subir une prédation intraguilde. Mes résultats montrent qu'en l'absence de pucerons, H. axyridis a un comportement de prédation vis-à-vis des œufs et de tous les stades larvaires d’A. bipunctata. La présence de pucerons, suivant leur densité, peut modifier cette interaction à l’égard des larves indigènes mais pas des œufs. En plus de la prédation intraguilde, une compétition par exclusion peut être aussi suspectée et expliquée par le comportement très agressif d’H. axyridis à l’égard de ses concurrents. Quant aux épines dorsales, elles permettent de réduire significativement le nombre de morsures et complètent ainsi les autres lignes de défense utilisées par H. axyridis pour s’imposer dans des ressources déjà exploitées par d’autres prédateurs. En conditions semi-naturelles, cette prédation à l’égard des coccinelles indigènes a été confirmée vis-à-vis d’Adalia spp. Calvia spp. Coccinella septempunctata L. et Propylea quatuordecimpunctata (L.). Vu le nombre de sites où cette prédation a été détectée, elle peut être considérée comme une interaction fréquente. De plus, une même larve de coccinelle asiatique peut ingérer plusieurs espèces de coccinelles indigènes confirmant indéniablement son statut de prédateur de coccinelles. Ainsi, nous pouvons conclure que la prédation intraguilde par H. axyridis sur les coccinelles indigènes participe très certainement au déclin de celles-ci et ceci très probablement au même titre que des phénomènes de compétition pour les ressources.
Doctorat en Sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished

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Doson, Coll Yago. "Stable isotope analysis of Rivers Inlet sockeye salmon (Oncorhynchus nerka) : investigating the contribution of environmental conditions in the high seas to British Columbia population declines." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/53245.

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Sockeye salmon (Oncorhynchus nerka) populations in BC have undergone varying degrees of decline coinciding with a shift to a warmer phase of the Pacific Decadal Oscillation (PDO) in 1977. The PDO, and other climate cycles, have been shown to significantly affect the physical and biological characteristics of the North East Pacific Ocean. Changes in ocean productivity have implications for pelagic food webs and may cause shifts in the abundance of potential prey for sockeye salmon, impacting their long-term production patterns. We investigated the coupling of ocean conditions and population fluctuations using Rivers Inlet as a case study, a system that suffered probably the most catastrophic sockeye stock collapse in BC history. Stable isotope analysis was used to access information on ocean conditions stored in the carbon and nitrogen isotope ratios of archived sockeye scales for the period 1915-2013. Our results indicated that Rivers Inlet sockeye salmon experienced highly variable open ocean conditions during this period. Both decadal scale shifts in North Pacific climate (e.g., PDO) and interannual scale shifts in climate (e.g., El Niño/La Niña events) were reflected in the physical and biological environment of the offshore Gulf of Alaska. Positive phases of the PDO and El Niño events were associated with a warmer and less productive ocean, while negative phases of the PDO and La Niña events were associated with a colder and more productive ocean. Moreover, the carbon and nitrogen stable isotope time-series indicated that the foraging habits of Rivers Inlet sockeye salmon were affected by these shifts of North Pacific climate. A lengthening (shortening) of the food web was associated to warm (cold) and less productive (more productive) periods. In addition, the isotope data also supports Rivers Inlet sockeye salmon shifting diet depending upon prey availability. We concluded that a combination of the two factors was responsible for the changes in the feeding ecology of Rivers Inlet sockeye salmon during the period 1915-2013. Such variation in the feeding ecology of Rivers Inlet sockeye salmon could potentially have a negative effect in the overall survival rates of sockeye salmon.
Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate

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38

Campbell, Robert Timothy. "'Declare a capital offence' : a retrospective view of Irish country houses and villas in the rural and urban environment." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318928.

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Yulia, Endah. "The decline of the red flowering gum (Corymbia Ficifolia (F Muell) K.D. Hill & L.A.S. Johnson) in urban environments in Western Australia : the role of fungal and oomcete pathogens." Thesis, Yulia, Endah (2012) The decline of the red flowering gum (Corymbia Ficifolia (F Muell) K.D. Hill & L.A.S. Johnson) in urban environments in Western Australia : the role of fungal and oomcete pathogens. PhD thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/32425/.

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40

Chng, Soon Fang. "Microbial factors associated with the natural suppression of take-all in wheat in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University, Canterbury, New Zealand /." Diss., Lincoln University, 2009. http://hdl.handle.net/10182/863.

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Take-all, caused by the soilborne fungus, Gaeumannomyces graminis var. tritici (Ggt), is an important root disease of wheat that can be reduced by take-all decline (TAD) in successive wheat crops, due to general and/or specific suppression. A study of 112 New Zealand wheat soils in 2003 had shown that Ggt DNA concentrations (analysed using real-time PCR) increased with successive years of wheat crops (1-3 y) and generally reflected take-all severity in subsequent crops. However, some wheat soils with high Ggt DNA concentrations had low take-all, suggesting presence of TAD. This study investigated 26 such soils for presence of TAD and possible suppressive mechanisms, and characterised the microorganisms from wheat roots and rhizosphere using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). A preliminary pot trial of 29 soils (including three from ryegrass fields) amended with 12.5% w/w Ggt inoculum, screened their suppressiveness against take-all in a growth chamber. Results indicated that the inoculum level was too high to detect the differences between soils and that the environmental conditions used were unsuitable. Comparison between the Ggt DNA concentrations of the same soils collected in 2003 and in 2004 (collected for the pot trial), showed that most soils cropped with 2, 3 and 4 y of successive wheat had reduced Ggt DNA concentrations (by 195-2911 pg g-1 soil), and their disease incidences revealed 11 of the 29 test soils with potential take-all suppressiveness. Further pot trials improved the protocols, such that they were able to differentiate the magnitudes of suppressiveness among the soils. The first of the subsequent trials, using 4% w/w Ggt inoculum level, controlled conditions at 16°C, 80% RH with alternate 12 h light/dark conditions, and watering the plants twice weekly to field capacity (FC), screened 13 soils for their suppressiveness against take-all. The 13 soils consisted of 11 from the preliminary trial, one wheat soil that had been cropped with 9 y of wheat (considered likely to be suppressive), and a conducive ryegrass soil. The results revealed that 10 of these soils were suppressive to take-all. However, in only four of them were the effects related to high levels of microbial/biological involvement in the suppression, which were assessed in an experiment that first sterilised the soils. In a repeat trial using five of the soils H1, H3, M2, P7 (previously cropped with 3, 3, 4 and 9 y successive wheat, respectively) and H15 (previously cropped with 5 y of ryegrass), three of them (H1, H3 and M2) had reduced Ggt DNA concentrations (>1000 pg g-1 soil reductions), and were confirmed to be suppressive to take-all. A pot trial, in which 1% of each soil was transferred into a γ-irradiated base soil amended with 0.1% Ggt inoculum, indicated that soils H1 and H3 (3 y wheat) were specific in their suppressiveness, and M2 (4 y wheat) was general in its suppressiveness. The microbial communities within the rhizosphere and roots of plants grown in the soils, which demonstrated conduciveness, specific or general suppressiveness to take-all, were characterised using PCR-DGGE, and identities of the distinguishing microorganisms (which differentiated the soils) identified by sequence analysis. Results showed similar clusters of microorganisms associated with conducive and suppressive soils, both for specific and general suppression. Further excision, re-amplification, cloning and sequencing of the distinguishing bands showed that some actinomycetes (Streptomyces bingchengensis, Terrabacter sp. and Nocardioides sp.), ascomycetes (Fusarium lateritium and Microdochium bolleyi) and an unidentified fungus, were associated with the suppressive soils (specific and general). Others, such as the proteobacteria (Pseudomonas putida and P. fluorescens), an actinomycete (Nocardioides oleivorans), ascomycete (Gibberella zeae), and basidiomycete (Penicillium allii), were unique in the specific suppressiveness. This indicated commonality of some microorganisms in the take-all suppressive soils, with a selected distinguishing group responsible for specific suppressiveness. General suppressiveness was considered to be due to no specific microorganisms, as seen in soil M2. An attempt to induce TAD by growing successive wheat crops in pots of Ggt-infested soils was unsuccessful with no TAD effects shown, possibly due to variable Ggt DNA concentrations in the soils and addition of nutrients during the experiment. Increasing numbers of Pseudomonas fluorescens CFU in the rhizosphere of plants, during successive wheat crops was independent of the Ggt DNA concentrations and disease incidence, suggesting that increases in P. fluorescens numbers were associated with wheat monoculture. This study has demonstrated that TAD in New Zealand was due to both specific and general suppressiveness, and has identified the distinguishing microorganisms associated with the suppression. Since most of these distinguishing microorganisms are known to show antagonistic activities against Ggt or other soilborne pathogens, they are likely to act as antagonists of Ggt in the field. Future work should focus on validating their effects either individually, or interactively, on Ggt in plate and pot assays and under field conditions.

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41

Distel, Christopher A. "Effects of an Insecticide on Competition in Anurans: Could Pesticide-Induced Competitive Exclusion be a Mechanism for Amphibian Declines?" Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1280363910.

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Georgii, Linnea. "How Do Long-Term Declines in Anthropogenic Sulfur Dioxide Emissions and Sulfate Wet Deposition Compare with Trends in Freshwater Chemistry in Scandinavian Rivers?" Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326709.

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Acidification of precipitation is an important environmental problem that emerged during the past century, especially after the Second World War. Acidification was primarily caused by human-made emissions of SOx (mostly SO2) and NOx, which are oxidized sulfur and nitrogen gases. The main sources of anthropogenic SOx emissions are non-ferrous ore refining, and the burning of fossil fuels and biofuels. SO2 emitted to the atmosphere combines with water vapor to produce sulfuric acid, which is one of the main compounds responsible for acid precipitation. In the 1970s and 1980s, more strict regulations regarding emissions of air pollutants such as SOx were established in Western Europe and North America, which led to declining levels of SO2 emissions and by this, declining levels of acidification in surface waters. This project was preformed by assembling and analyzing existing, publicly- available datasets of anthropogenic SO2 emissions for the period 1970 to 2010 from ten different regions in the Northern Hemisphere, and compare them with SO42- concentrations in precipitation and river chemistry in Sweden and Norway for the same period. It was discovered that it is the SO2 emissions from Northwestern Europe, the UK & Ireland and from the USA that have the greatest influence over the SO42- concentration in Scandinavian rivers. The SO42- concentration in stream water is also declining faster than the concentration in precipitation, with a faster decline in the southern parts of Scandinavia.
Försurning av nederbörd är ett miljöproblem som uppstod under det senaste århundradet, särskilt efter andra världskriget. Försurningen orsakades främst av mänskliga utsläpp av SOx (mestadels SO2) och NOx, vilka är oxiderade svavel- och kvävgaser. Huvudkällorna för dessa antropogena SOx-utsläpp är malmförädling samt förbränning av fossila bränslen och biobränslen. SO2 som släpps ut i atmosfären reagerar med vattenånga och bildar svavelsyra, vilket är en av huvudföreningarna ansvarig för sur nederbörd. På 1970- och 1980-talet fastställdes strängare bestämmelser beträffande utsläpp av luftföroreningar (som SOx) i Västra Europa och i Nordamerika. Detta ledde till minskande nivåer av SO2-utsläpp och genom denna sänkning även en minskning av försurning av ytvatten. Det här arbetet utfördes genom att befintlig, offentligt tillgänglig data samlades in och analyserades. Antropogena SO2-utsläpp för perioden 1970-2010 från tio olika regioner på norra halvklotet jämfördes med koncentrationer av SO42- i nederbörd och i vattendrag i Sverige och Norge för samma period. Genom detta fastslogs att de regioner som har störst inflytande över koncentrationen i skandinaviska vattendrag är SO2-utsläpp från nordvästra Europa, Storbritannien och Irland samt från USA. SO42- koncentrationen i vattendragen sjunker också snabbare än koncentrationen i nederbörden, med en snabbare nedgång i de södra delarna av Skandinavien.

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Ndlovu, Nomzamo Bonisiwe. "Quantifying indigenous forest change in Dukuduku from 1960 to 2008 using GIS and remote sensing techniques to support sustainable forest management planning." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85622.

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Thesis (MSc)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: This study aimed to understand how Dukuduku Forest in Kwa-Zulu Natal has changed from 1960 to 2008 and whether the change in political regimes, during and post apartheid eras might have contributed to changes in forest extent. To achieve the aims, the following analyses were made: - Qualitative and quantitative spatial analyses of forest change; - Analyses of the correspondence of change with political changes in the country; - Assessment of perception of people living in the Dukuduku forest area. The Dukuduku land cover was mapped from aerial photos using ArcGIS 9.3 to determine whether or not there has been a significant change in the area from 1960-2008, in response to resource use pressures and to come up with the strategic sustainable management plan from the results found. Five aerial photographs were used to determine the changes in land cover from the year: 1960, 1970, 1992, 2005 and 2008. The Land cover types were classified into four classes, Indigenous Forests, Plantation Forests, Water Bodies and Other (open areas, cultivated land, and all the human disturbed and transformed land). The percentage of cover per class was compared across the years to determine overall change in land cover and the rate of change per year was also calculated. The results from the study showed that: - Natural Forest increased by 11% (700 ha), at the rate of 20.56 hectares per year between 1960 and 1992, which is the apartheid era. Between 1992 and 2008, the democratic era, the forest decreased by 34.4% (2472.31ha), at the rate of 168 hectares per year. - The Dukuduku forest community gains resources (timber and grass for construction, art, firewood, medicinal plants, grazing of livestock and food) from the forest. The people are willing to contribute in protecting the forest only if the governing authorities would include them in decisions made, as the NFA demands Participatory Forest Management, but which does not currently exist in Dukuduku.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die verandering van die Dukuduku woud in Kwa-Zulu Natal vanaf 1960 tot 2008, en vernaamlik of die verandering in politieke regimes tydens en in die postapartheid eras tot verandering bygedra het in die woud se vorm. Om hierdie doelwitte te breik is die volgende analises gedoen: - Kwalitatiewe en kwantitatiewe ruimtelike analises van woudverandering; - Analises van die korrelasie tussen hierdie fisiese omgewingsverandering en politieke verandering in die land; - Analise van die persepsie van mense wat in die Dukuduku woudgebied woon. Die Dukuduku gronddekking is gekarteer met behulp van lugfotos, waarvoor ArcGIS 9.3 gebruik is om te bepaal of daar noemenswaardige verandering in die gebied plaasgevind het van 1960 tot 2008, in reaksie op hulpbrongebruike, en om ‘n volhoubare bestuursplan gestel voor wat op die bevindinge gebaseer is. Vyf lugfotos is gebruik om verandering in gronddekking te bepaal vir die jare: 1960, 1970, 1992, 2005 en 2008. Die Gronddekking tipes is geklassifiseer in vier klasse naamlik Inheemse Woude, Plantasiebosse, Waterliggame en Ander (oop gebiede, landerye en al die mens-versteurde en getransfomeerde gebiede). Die persentasie van elke dekkingsklas is oor die jare vergelyk om die verandering in algehele grond-dekking te bepaal, en die tempo van verandering is ook bepaal, asook die tempo van verandering. Die resultate van die studie wys dat: - Die natuurlike woud toegeneem het met 11% (700 ha), teen ‘n tempo van 20.56 hektaar per jaar tussen 1960 en 1992, tgedurende die apartheidsera. Tussen 1992 en 2008, die demokratiese era, het die woude verminder met 34.4% (2472.31 ha), teen ‘n tempo van 168 hektaar per jaar. - Die gemeenskap wat in die Dukuduku woud woon verkry hulpbronne van die woud (hout en gras vir konstruksie, kuns, brandhout, medisinale plante, weiding vir vee, en voedsel). Die mense is gewillig om by te dra tot beskerming van die woud indien die owerhede hulle sou betrek in besluite wat geneem word, veral omdat die nasionale Wet op Bosse voorsiening maak vir Deelnemende Bosbestuur, wat tans nie by Dukuduku gebeur nie.

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44

Puech, Laurence. "Critères microstructuraux pour l'identification des causes abiotiques des dépérissements du sapin (Abies alba (Mill. )) et de l'épicéa (Picea abies (L. ) Karst. ) dans les Vosges et dans les Alpes dauphinoises externes." Université Joseph Fourier (Grenoble ; 1971-2015), 1995. http://www.theses.fr/1995GRE10175.

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Les deperissements forestiers observes depuis les annees 1970 chez les coniferes europeens resultent de l'action conjuguee de differents facteurs biotiques et abiotiques dont l'importance relative varie en fonction des sites. La presente etude vise a l'identification de stress abiotiques a partir de l'anatomie d'aiguilles de sujets atteints. Une comparaison de differents sites forestiers des vosges et des alpes dauphinoises externes avec des experimentations en conditions controlees a ete realisee. En conditions controlees, une augmentation de l'apport d'ammonium aggrave les effets de carences en magnesium sur de jeunes epiceas. Une augmentation de l'apport total d'azote provoque une stimulation de la xylogenese par le cambium secondaire, une diminution de l'accumulation d'amidon et une alteration des chloroplastes. L'exposition a des doses d'ozone augmentees provoque l'apparition de necroses dans le mesophylle et de cristaux intracellulaires d'oxalate de calcium chez de jeunes epiceas. Dans les aiguilles de l'annee de jeunes sapins, on observe une reduction de l'accumulation d'amidon alors que, dans les aiguilles de l'annee precedente, on observe de nombreuses necroses dans le parenchyme palissadique, une alteration des chloroplastes et une proliferation de cellules du parenchyme lacuneux. Sur le site des vosges, on retrouve l'effet des facteurs abiotiques etudies: un collapse du phloeme chez sapins et epiceas ainsi qu'une accumulation d'amidon chez l'epicea indiquent des carences en magnesium. Chez le sapin, la presence d'anomalies de croissance dans le cylindre central et dans le parenchyme lacuneux suggerent respectivement l'effet d'une augmentation de la nutrition azotee et de concentrations elevees l'ozone. Dans les sites des alpes dauphinoises externes, aucun signe de carences minerales n'est observable alors que des anomalies de croissance du mesophylle laissent suspecter une influence de l'ozone. Une lignification precoce a ete observee sur deux arbres de ces sites a l'aide de la met

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O'Rorke, Richard. "Correlations between a cyanobacteria bloom's decline and environmental dynamics." 2009. http://adt.waikato.ac.nz/public/adt-uow20090424.142438/index.html.

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46

Andrews, Shea J. "Predicting Cognitive Decline: Genetic, Environmental and Lifestyle Risk Factors." Phd thesis, 2017. http://hdl.handle.net/1885/116741.

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With advancing age individuals experience a deterioration in cognitive abilities that is characterized by substantial inter-individual variation in the observed trajectories of cognitive decline. Late onset Alzheimer’s disease (LOAD) susceptibility genes and environmental risk factors are good candidates for association with cognitive decline, as the pathological features of LOAD progress to varying degrees in individuals without dementia or cognitive impairment and are associated with nonclinical cognitive decline. This thesis investigates whether Alzheimer’s disease risk factors and genetic variants previously associated with cognitive function are also associated with cognitive decline. Data collected from the 60+ cohort of the Personality and Total Health (PATH) through life project was used, in which 2,551 participants were assessed at 4-year intervals for a total of 12 years on a comprehensive battery of cognitive tests. The publications in this thesis investigate the following. First, whether APOE*4 moderates the association between high blood pressure and cognitive function in late life. It was observed that a APOE–hypertension interaction was associated with a small but statistically significant increase in the rate of decline of episodic memory, verbal ability and global cognition. In contrast, the interaction between APOE and mean arterial pressure interaction had no effect on rate of decline. Second, the role of 25 LOAD risk loci in non-linear cognitive change was examined, both individually and collectively as a genetic risk score (GRS). Twelve LOAD risk loci were associated with baseline cognitive performance (ABCA7, MS4A4E, SORL1), linear rate of change (APOE, ABCA7, EPHA1, INPP5D, ZCWPW1, CELF1) or quadratic rate of change (APOE, CLU, FERMT2). In addition, a weighted GRS was associated with linear rate of change in episodic memory and information processing speed. Third, the role of 9 single nucleotide polymorphisms that have been previously associated with cognitive performance was further examined, with 6 SNPs observed to be associated with baseline cognitive performance (BDNF, PDE7A, AKAP6), linear rate of change (COMT, CTNNBL1, PDE7A) or quadratic rate of change (MIR2113). Finally, it was examined whether a risk score comprised of lifestyle, medical and demographic factors (the Australian National University Alzheimer’s disease Risk Index; ANU-ADRI) and a LOAD GRS were predictors of progression to Mild Cognitive Impairment (MCI). A higher ANU-ADRI score was associated with a higher probability of transitioning from normal cognition to cognitive impairment, while the GRS was associated with an increased risk of transitioning from normal cognition to dementia. These results suggest that a subset of LOAD related SNPs may be associated with cognitive decline. However, the effect size of each locus is small and when demographic and lifestyle factors are taken into account, neither individual SNPs nor GRS explain a significant proportion of the variance in cognitive decline in our sample. Further research is required to verify these results and to examine the effect of preclinical LOAD in genetic association studies of cognitive decline. The identification of LOAD risk loci associated with cognitive performance may help in screening for individuals at greater risk of cognitive decline

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47

Jung, Robin Elizabeth. "The potential influence of environmental pollution on amphibian development and decline." 1996. http://catalog.hathitrust.org/api/volumes/oclc/36492174.html.

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48

Lin, Yu-Hsiang, and 林于翔. "On the Decline of Qing Dynasty from the Perspective of Environmental Factors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/mdtu9u.

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碩士
國立中央大學
歷史研究所
106
During the dynasty of Jiaqing and Daoguang, environmental variation started to appear one after and other. The area of the forest reduced a lot, grass gradually appeared, ecosystem damaged hugely; abnormal weather also was a major cause, highly related to the “sunspot minimum”. Human destroy biophysical environment, in order to face the rebounce of nature, varieties of disaster come in a throng. Based on the related statistical results showed, during the period of Jiaqing and Daoguang, “chilling injury”, “drought”, and “locust plague” occurred much more frequently compared with the era of Kangxi, Yongzheng, and Qianlong. Especially drought and locus plague. Emperors prayed for the rain repeatedly, people built temples everywhere, but those disasters eventually highly related to the man-made factors. Reclamation of forests, damage of vegetation, and scarce forests caused a catalytic effect to the drought, also increased the frequency of droughts. Unbalance of the ecosystem caused the natural enemies of locusts drop sharply and increased the possibility of locust plague. Waterlogging and river disaster happened frequently especially during the period of Daoguang. Based on the statistic results, era of Jiaqing and Daoguang seems not that severe compared to the era of Kangxi, Yongzheng, and Qianlong. But if we evaluate from the dimension of single dynasty, the ratio and average number of waterlogging and river disaster during the period of Daoguang was higher than the period of Kangxi and Qianlong. Even easily appeared the situation about “people drowning and house destruction”, “river burst and drifting farm land”, and “a few deep feet water” happened. River disaster was a long-term challenge. If we take comprehensive statistic of river disaster of Yellow River, Yungting River, and Huaihe River to see, period of Jiaqing and Daoguang were truly higher than the period of Kangxi, Yongzheng, and Qianlong. Although the ecological crisis during the era of Jiaqing and Daoguang which included drought, locust plague, waterlogging, and river disaster was getting worse and worse, deeply influenced the prosperity and decline of Qing Dynasty. Dominators still had solutions at the point, with the rapid growth of population, the era of Qianlong has grown explosively. The population already broke through to four billion which caused the deterioration of human-environment relationship. However, promotion of sweet potato and corns was also a major cause. Both of the sweet potato and corns were good at drought tolerance with short growing period, also are highly adaptable species, they had already become the most important food for those who suffered. Besides the growing population, the way of planting also caused the damage of the environment. And the climate also caused a direct correlation of the population growth, deeply influenced the potential productive forces and the cause of natural disasters. The growth of population also brought potential worries, excessive growth caused declining quantity of land per capita. In order to survive, human went to reclaim the border also caused the problem of deforestation. The governor in order to reduce the population pressure, they unexpectedly let people to develop the area which was very far-off and caused a lot of refugees and turmoil. The improper behavior of the government caused severe resentment. The way how government handled everything caused the chaos even more pessimistic. The epidemic disease occurred at the late period of Jiaqing , it was also occurred pretty often while the beginning period of Daoguang. When governments no longer be able to give expectance to their people, just like the White Lotus Rebellion and the Taiping Heavenly Kingdom and etc., social unrest started to occur, era of Jiaqing and Daoguang became the key of the prosperity and decline of Qing dynasty.

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Kulick, Erin Ryan. "Long-term Exposure to Ambient Air Pollution and Trajectories of Cognitive Decline in Northern Manhattan." Thesis, 2018. https://doi.org/10.7916/D8N02Q45.

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Age-related cognitive decline is a growing public health issue as increases in life expectancy are expected to substantially raise the prevalence of cognitive impairment and dementia. An estimated 46.8 million individuals are currently living with dementia, with the global prevalence expected to double every 20 years. Emerging evidence suggests that ambient air pollution from traffic and other sources may be an important risk factor for cognitive decline in addition to its association with other cardiovascular and neurological outcomes. The aim of this dissertation was to first investigate the association between long-term exposure to ambient air pollution and cognitive decline among older adults in an urban population within Northern Manhattan. I then set out to assess specific mechanisms involved in the association between long-term exposure to ambient air pollution and cognitive decline, specifically investigating the ApoE4 allele, age, and current smoking behavior as effect modifiers of the association between long-term exposure to ambient air pollution and cognitive decline. I found evidence of an adverse effect of ambient air pollution on the cognitive functioning of older adults. Overall, exposure to higher levels of ambient air pollution was highly predictive of lower cognitive scores, but at baseline only. Contrary to the current hypothesis, limited evidence was found for an association between estimates of air pollution and trajectories of cognitive decline. The patterns of effect were similar across pollutant types and cognitive domains in this aging, urban population. I found strong evidence of effect modification by smoking status, where contrary to the hypothesis; the overall effects of ambient air pollution on cognition and cognitive decline were stronger among individuals who never smoked. The impact of effect modification by age category was most prominent in the memory and language cognitive domains. Among individuals less than 75 years old at baseline, there was a stronger association between a one IQR increase in air pollutants and cognitive domain scores at baseline as compared to individuals 75 years and older. I did not observe conclusive evidence of an association between air pollution and cognition in models stratified by APOE-4 status. To my knowledge, this is the largest study to analyze the association of ambient air pollution on cognition and cognitive decline over time in a racially and ethnically diverse sample. These results further support the current evidence on the role of air pollution on accelerated cognitive aging and brain health.

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Franzi, Cathryn Vanessa. "An Australian botanical narrative : a practice-led enquiry into representations of Australian flora on the ceramic vessel as an expression of environmental culture." Phd thesis, 2015. http://hdl.handle.net/1885/109317.

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This practice-led research investigates ways in which representations of Australian flora on ceramic vessels can communicate ideas about current environmental culture. The project developed from a curiosity about whether changing attitudes to Australia's environment, from colonisation to the present time of unprecedented species decline, might be found reflected on historical and contemporary ceramic objects. Botanical exploration and the scientific study of Australia's vast flora have produced a rich resource of natural history documentation. The aim was to establish a framework specific to the project that utilises these resources and current theoretical and practical approaches to understanding flora and the environment in both the sciences and humanities. Through this interdisciplinary enquiry, visual arts and botanical research methodologies intersected in the studio informing material, technical and conceptual developments. This exploration takes the form of an installation of wheel thrown vessels with carved and inlaid surface imagery of Australian flora, where, through form, imagery, material and placement, a metaphorical space is made in which to reflect on current environmental culture.

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