Дисертації з теми "Responses to climate change"
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Merk, Christine [Verfasser]. "Essays on individuals’ responses to climate change and technologies to counteract climate change / Christine Merk." Kiel : Universitätsbibliothek Kiel, 2016. http://d-nb.info/1105472159/34.
Повний текст джерелаNorton, L. R. "The responses of plant populations to climate change." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320820.
Повний текст джерелаBarichivich, J. "Responses of boreal vegetation to recent climate change." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/49468/.
Повний текст джерелаO'dea, Sarah Aisling. "Calcareous nannoplankton responses to early Paleogene climate change." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/359135/.
Повний текст джерелаPilla, Rachel M. "Lake Temperatures as Sentinel Responses to Climate Change." Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1443090263.
Повний текст джерелаCornish, Laura M. "Can 4D visioning foster community responses on climate change?" Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44085.
Повний текст джерелаDippold, David Arthur. "Responses of an exploited fish population to environmental change." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1606136495171641.
Повний текст джерелаKosanic, Aleksandra. "Ecological responses to climate variability in west Cornwall." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/18120.
Повний текст джерелаFeatherstone, Helen Clare. "Risk communication of climate change: stakeholder objectives and public responses." Thesis, University of the West of England, Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.490458.
Повний текст джерелаMason, Suzanna. "Examining species' responses to climate change across multiple taxonomic groups." Thesis, University of York, 2017. http://etheses.whiterose.ac.uk/19677/.
Повний текст джерелаTang, Samuel Wa Sun. "Corporate responses to climate change reporting requirements in the UK." Thesis, King's College London (University of London), 2016. https://kclpure.kcl.ac.uk/portal/en/theses/corporate-responses-to-climate-change-reporting-requirements-in-the-uk(544e2c92-281e-46d2-a2c7-0cd848e095ee).html.
Повний текст джерелаKinkese, Theresa. "Climate change impacts and farmers' responses in Chilanga District, Zambia." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27524.
Повний текст джерелаLeviston, Zoe. "The social and psychological functions of responses to climate change." Thesis, Curtin University, 2013. http://hdl.handle.net/20.500.11937/1794.
Повний текст джерелаGooding, Rebecca Ann. "Multiple abiotic changes and species interactions mediate responses to climate change on rocky shores." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45550.
Повний текст джерелаPellerin, Félix. "Species responses to climate change and landscape fragmentation : the central role of dispersal." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30085.
Повний текст джерелаContemporary climate change is leading to population extinction, range shift and composition changes. Dispersal shapes these two last responses by allowing colonization of new habitats and by affecting population composition through gene flow. Depending on its adaptiveness, dispersal can promote or hinder local adaptation and modify the relative influence of phenotypic plasticity and evolutionary adaptation in population phenotypic change. However, landscape fragmentation hampers dispersal, affecting both population responses to climate change, and modifying the relative influence of the different processes involved in these responses. The aim of this PhD was to understand how population responses to climate change could be influenced by landscape fragmentation and by dispersal. By monitoring lizards inhabiting experimental populations where both climatic conditions and connectivity among them were manipulated, we demonstrated that connectivity among populations buffered climate change effects on population dynamics and phenotypic composition. We found that dispersal decisions depended on multiple intrinsic and extrinsic factors allowing to reduce the influence of warmer climate on population dynamics, but decreasing population density in cooler climate. Surprisingly, we also found that dispersal could modify the strength and direction of climate-dependent selection pressures on phenotypes. As a consequence, selection and dispersal acted in synergy to counteract the plastic response of the individuals. When integrated into a model, similar adaptive dispersal behavior strongly altered predictions of species persistence under climate change. We indeed found that adaptive dispersal promoted species range shift and reduced extinction probability compared to a model where dispersal was random (i.e.independent of intrinsic and extrinsic factors). Rather than considering dispersal as a neutral process, our results highlighted the importance to consider it as a complex mechanism shaped by multiple factors and able to drive population responses to climate change. Our results further suggest that fragmentation could strongly increase the influence of climate change on populations and may therefore precipitate their extinction. We thus call for a better integration of dispersal and landscape structure when studying population responses to climate change
Dryhurst, Sarah. "Traits as units for prediction in ecological responses to climate change." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24427.
Повний текст джерелаBórnez, Mejías Kevin. "Study of vegetation dynamics from satellite: phenological responses to climate change." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/673693.
Повний текст джерелаLa fenología es clave para controlar los procesos fisicoquímicos y biológicos, especialmente el albedo, la rugosidad superficial, conductancia de las hojas, flujos de carbono, agua y energía. Por lo tanto, la estimación de la fenología es cada vez más importante para comprender los efectos del cambio climático en los ecosistemas y las interacciones biosfera-atmósfera. La teledetección es una herramienta útil para caracterizar la fenología, aunque no existe consenso sobre el tipo de sensor satelital y metodología óptimos para extraer métricas fenológicas. Los objetivos principales de mi investigación fueron (i) mejorar la estimación de la fenología vegetal a partir de datos satelitales, (ii) validar las estimaciones fenológicas con observaciones terrestres y teledetección cercana a la superficie, y (iii) comprender las relaciones entre las variables climáticas y la fenología en un contexto de cambio climático, así como evaluar las respuestas de la vegetación a eventos extremos. Estos objetivos se exploran en los siguientes tres capítulos de la tesis. En el capítulo 2, investigué la sensibilidad de la fenología a (I) la variable de vegetación: índice de vegetación NDVI, índice de área foliar (LAI), fracción de radiación fotosintéticamente activa absorbida (FAPAR) y fracción de cubierta vegetal (FCOVER); (II) el método de suavizado para derivar trayectorias estacionales; y (III) el método de estimación fenológica: umbrales, función logística, media móvil y primera derivada. El método basado en umbrales aplicado a la serie temporal Copernicus Global Land LAI V2 suavizada dio resultados óptimos al validarlos con observaciones terrestres, con errores cuadráticos medios de ~10 d y ~25 d para el inicio de estación fenológica y la senescencia respectivamente. En el tercer capítulo, utilicé medidas fenológicas continuas de PhenoCam y FLUXNET a alta resolución temporal (30 minutos). Esto permite una comparación más robusta y precisa con la fenología estimada a partir de satélite, evitando problemas relacionados con las diferencias en la definición de métricas fenológicas. Validé la fenología estimada a partir de series de tiempo de LAI con PhenoCam y FluxNet en 80 bosques caducifolios. Los resultados mostraron una fuerte correlación (R2 > 0,7) entre la fenología obtenida mediante teledetección y las observaciones terrestres para el inicio de estación y R2 > 0,5 para el final de estación. El método basado en umbrales funcionó mejor con un error cuadrático medio de ~9 d con PhenoCam y ~7 d con FLUXNET para el inicio de estación, y ~12 d y ~10 d, respectivamente, para la senescencia. En el cuarto capítulo, investigué los patrones espacio-temporales de la respuesta fenológica a las anomalías climáticas en el hemisferio norte utilizando la fenología estimada en el Capítulo 2 y validado en el Capítulo 2 y Capítulo 3, y conjuntos de datos climáticos de múltiples fuentes para 2000-2018 a resoluciones de 0.1°. También evalué el impacto de las olas de calor extremas y las sequías en la fenología. Los análisis de correlación parcial de las métricas fenológicas estimadas con satélite y las variables climáticas, indicaron que los cambios en la temperatura pre estacional tuvieron mayor influencia sobre las anomalías fenológicas que la precipitación: cuanto mayor es la temperatura, más temprano es el comienzo estacional en la mayoría de los bosques caducifolios (coeficiente de correlación medio de -0,31). Tanto la temperatura como la precipitación contribuyeron al avance y retraso del final de estación. Un atraso en la senescencia se correlacionó significativamente con un índice de precipitación-evapotranspiración estandarizado (SPEI) positivo (~ 30% de los bosques). El final e inicio de estación cambió >20 d en respuesta a la ola de calor en la mayor parte de Europa en 2003 y en los Estados Unidos de América en 2012.
Phenology is key to control physicochemical and biological processes, especially albedo, surface roughness, canopy conductance and fluxes of carbon, water and energy. High-quality retrieval of land surface phenology (LSP) is thus increasingly important for understanding the effects of climate change on ecosystem function and biosphere–atmosphere interactions. Remote sensing is a useful tool for characterizing LSP although no consensus exists on the optimal satellite dataset and the method to extract phenology metrics. I aimed to (i) improve the retrieval of Land Surface Phenology from satellite data, (ii) validate LSP with ground observations and near surface remote sensing, and (iii) understand the relationships between climate variables and phenology in a climate change context, as well as to assess the responses of vegetation to extreme events. These three main research objectives are explored in the three chapters of the thesis. In chapter 2, I investigated the sensitivity of phenology to (I) the input vegetation variable: normalized difference vegetation index (NDVI), leaf area index (LAI), fraction of absorbed photosynthetically active radiation (FAPAR), and fraction of vegetation cover (FCOVER); (II) the smoothing and gap filling method for deriving seasonal trajectories; and (III) the phenological extraction method: threshold, logistic-function, moving-average and first derivative based approaches. The threshold-based method applied to the smoothed and gap-filled Copernicus Global Land LAI V2 time series agreed the best with the ground phenology, with root mean square errors of ~10 d and ~25 d for the timing of the start of the season (SoS) and the end of the season (EoS), respectively. In the third chapter, I took advantage of PhenoCam and FLUXNET capability of continuous monitoring of vegetation seasonal growth at very high temporal resolution (every 30 minutes). This allows a more robust and accurate comparison with LSP derived from satellite time series avoiding problems related to the differences in the definition of phenology metrics. I validated LSP estimated from LAI time series with near-surface PhenoCam and eddy covariance FLUXNET data over 80 sites of deciduous broadleaf forest. Results showed a strong correlation (R2 > 0.7) between the satellite LSP and ground-based observations from both PhenoCam and FLUXNET for the timing of the start (SoS) and R2 > 0.5 for the end of season (EoS). The threshold-based method performed the best with a root mean square error of ~9 d with PhenoCam and ~7 d with FLUXNET for the timing of SoS, and ~12 d and ~10 d, respectively, for the timing of EoS. In the fourth chapter, I investigated the spatio-temporal patterns of the response of deciduous forests to climatic anomalies in the Northern Hemisphere using LSP derived in Chapter 1 and validated in Chapter 1 and Chapter 2, and multi-source climatic data sets for 2000–2018 at resolutions of 0.1°. I also assessed the impact of extreme heatwaves and droughts on deciduous forest phenology. Analyses of partial correlations of phenological metrics with the timing of the start of the season (SoS), end of the season (EoS), and climatic variables indicated that changes in preseason temperature played a stronger role than precipitation in the interannual variability of SoS anomalies: the higher the temperature, the earlier the SoS in most deciduous forests in the Northern Hemisphere (mean correlation coefficient of -0.31). Both temperature and precipitation contributed to the advance and delay of EoS. A later EoS was significantly correlated with a positive standardized precipitation-evapotranspiration index (SPEI) at the regional scale (~30% of deciduous forests). The timings of EoS and SoS shifted by >20 d in response to heat waves throughout most of Europe in 2003 and in the United States of America in 2012.
Universitat Autònoma de Barcelona. Programa de Doctorat en Ecologia Terrestre
Cass, Noel. "Local authority responses to climate change : a discursive and cultural analysis." Thesis, Lancaster University, 2003. http://eprints.lancs.ac.uk/83022/.
Повний текст джерелаMair, Louise. "The responses of British butterflies to four decades of climate change." Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/6228/.
Повний текст джерелаMorris, Thomas. "Monitoring the Knysna forest : species, community and forest responses." Bachelor's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/26490.
Повний текст джерелаFitzsimmons, James. "Ecological Responses to Threats in an Evolutionary Context: Bacterial Responses to Antibiotics and Butterfly Species’ Responses to Climate Change." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23807.
Повний текст джерелаBourguignon, Marie. "Ecophysiological Responses of Tall Fescue Genotypes to Endophyte Infection and Climate Change." UKnowledge, 2013. http://uknowledge.uky.edu/pss_etds/28.
Повний текст джерелаAndrews, Christopher James. "Human responses to climate change during the Younger Dryas in Northwest Europe." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/276744.
Повний текст джерелаMcClure, Lachlan John. "Planning for climate change adaptation in a neoliberal context: Influences and responses." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/95113/1/Lachlan_McClure_Thesis.pdf.
Повний текст джерелаWilliams, Keith David. "Evaluating cloud response to climate change." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422781.
Повний текст джерелаTrofimov, Siliviu. "Structural and functional responses to elevated COâ†2 in simulated turves of chalk grassland." Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263209.
Повний текст джерелаAnderton, Karen L. "Sub-national government responses to reducing the climate impact of cars." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:806e646b-ff12-4e78-b412-55422e6f8da3.
Повний текст джерелаAleryd, Sarah, and Garpenholt Lydia Frassine. "From Climate Change to Conflict : An analysis of the climate-conflict nexus in communications on climate change response." Thesis, Högskolan för lärande och kommunikation, Jönköping University, HLK, Globala studier, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49218.
Повний текст джерелаMcKee, Ian Fraser. "Plant physiological and growth responses to elevated concentrations of atmospheric COâ†2." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241094.
Повний текст джерелаHill, Spencer Alan. "Energetic and hydrological responses of Hadley circulations and the African Sahel to sea surface temperature perturbations." Thesis, Princeton University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10167545.
Повний текст джерелаTropical precipitation is linked through the moist static energy (MSE) budget to the global distribution of sea surface temperatures (SSTs), and large deviations from the present-day SST distribution have been inferred for past climates and projected for global warming. We use idealized SST perturbation experiments in multiple atmospheric general circulation models (AGCMs) to examine the hydrologic and energetic responses in the zonal mean and in the African Sahel to SST perturbations. We also use observational data to assess the prospects for emergent constraints on future rainfall in the Sahel.
The tropical zonal mean anomalous MSE fluxes in the NOAA Geophysical Fluid Dynamics Laboratory (GFDL) AM2.1 AGCM due to SST anomalies caused by either historical greenhouse gas or aerosol forcing primarily occur through the time-mean, zonal mean (Hadley) circulation. Away from the Intertropical Convergence Zone (ITCZ), this largely stems from altered efficiency of the Hadley circulation energy transport, i.e. the gross moist stability (GMS). A thermodynamic scaling-based estimate that relates GMS change to the local climatological moisture and temperature change relative to the ITCZ captures most of the qualitative GMS responses. It also yields a heuristic explanation for the well known correlation between low-latitude MSE fluxes and the ITCZ latitude.
Severe Sahelian drying with uniform SST warming in AM2.1 is eliminated when the default convective parameterization is replaced with an alternate. The drying is commensurate with MSE convergence due to suppressed ascent balanced by MSE divergence due to increased dry advection from the Sahara. These qualitative energetic responses to uniform warming are shared by five other GFDL models and ten CMIP5 models, although they do not translate into quantitative predictors of the Sahel rainfall response. Climatological values and interannual variability in observations and reanalyses suggest that drying in AM2.1 is exacerbated by an overly top-heavy ascent profile and positive feedbacks through cloud radiative properties. Simulations with patterned SST anomalies suggest a major role for mean SST variations in discrepancies among models and potentially in observed decadal variations of Sahelian precipitation.
Clement, Viviane. "From Adaptation to Transformation| A Resilience Perspective on Organizational Responses to Ecological Adversity." Thesis, The George Washington University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10619173.
Повний текст джерелаHow do firms adapt to the intensity of adverse conditions stemming from the natural environment (ecological adversity intensity)? In this dissertation, I develop several lines of inquiry in exploring this question. First, I seek to contribute to generally diverging perspectives on organizational adaptation, which view firms as either inherently constrained or capable of continuous adaptation to fit their environment. To do this, I examine the conditions under which firms are more likely to adapt to different levels of ecological adversity intensity. My findings from a 13-year longitudinal analysis of western U.S. ski resorts’ adaptation to temperature conditions indicate that firms facing moderate ecological adversity intensity appear more likely to engage in higher adaptation levels while those experiencing low and high ecological adversity intensity show a tendency for lower adaptation levels. That is, both diverging perspectives may predict part of firms’ adaptive responses to ecological adversity intensity. My findings also suggest firms may encounter limits to adaptation when facing increasing ecological adversity intensity. I also undertake a post hoc exploration of firm and institutional environment level factors that may moderate the relationship between ecological adversity intensity and firm adaptation. Second, I use an interdisciplinary approach that draws from resilience theory in socioecology to suggest that the existing conceptualization of organizational resilience could be expanded to include transformative change, which may allow firms to mitigate the operational impacts of reaching adaptation limits. Third, I also consider the resilience implications of the interdependency between firms and the broader ecosystems in which they operate. I conclude with potential avenues for future research in this area.
Vazquez, Tyara Kiileialohalani. "Physiological Responses to Heat-stress in a Desert Montane Lizard." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544789284098965.
Повний текст джерелаJung, Huicheul. "Modeling the ecological and hydrological responses to climate change in the Korean Peninsula." 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/126599.
Повний текст джерела0048
新制・課程博士
博士(地球環境学)
甲第14885号
地環博第62号
新制||地環||12(附属図書館)
27307
UT51-2009-K681
京都大学大学院地球環境学舎地球環境学専攻
(主査)教授 松岡 譲, 教授 藤井 滋穂, 准教授 倉田 学児
学位規則第4条第1項該当
Schwartz, Elizabeth. "Local solutions to a global problem? : Canadian municipal policy responses to climate change." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57737.
Повний текст джерелаArts, Faculty of
Political Science, Department of
Graduate
Wolf, Johanna. "Climate change and citizenship : a case study of responses in Canadian coastal communities." Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435095.
Повний текст джерелаDymond, Caren. "Disturbance and climate change risks to forest carbon sinks and potential management responses." Thesis, Bangor University, 2018. https://research.bangor.ac.uk/portal/en/theses/disturbance-and-climate-change-risks-to-forest-carbon-sinks-and-potential-management-responses(416a28ec-8724-43f6-a415-513772dd7dc2).html.
Повний текст джерелаHarris, V. "Modelling multivariate spatio-temporal structure in ecological data and responses to climate change." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1388074/.
Повний текст джерелаHaney, Aoife Brophy. "The evolution of firms' strategic responses to climate change : information, capabilities and impact." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648572.
Повний текст джерелаKaarlejärvi, Elina. "The role of herbivores in mediating responses of tundra ecosystems to climate change." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-85208.
Повний текст джерелаMackay, Helen. "Testing peatland carbon responses to late Holocene climate change in eastern North America." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/386576/.
Повний текст джерелаBoisvenue, Céline. "Assessing forest responses to climate change and resolving productivity measurements across spatial scales." Diss., [Missoula, Mont.] : The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-01042008-115155/.
Повний текст джерелаRostö, Evelina. "Changes in alpine plant population sizes in response to climate change." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-418248.
Повний текст джерелаDiaw, Adja Adama. "Agricultural practices and perceptions of climate change in Keur Samba Guéye village, Senegal, West Africa." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/50976.
Повний текст джерелаMaster of Science
Yin, Yunzhu. "Morphodynamic response of estuaries to climate change." Thesis, Swansea University, 2018. https://cronfa.swan.ac.uk/Record/cronfa39604.
Повний текст джерелаReynolds, Lorien. "Soil-Climate Feedbacks: Understanding the Controls and Ecosystem Responses of the Carbon Cycle Under a Changing Climate." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20465.
Повний текст джерелаSpringate, David. "Plastic and genetic responses to environmental changes." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/plastic-and-genetic-responses-to-environmental-changes(df87fd0e-c8a5-43ad-81d4-e0b0a1e25b44).html.
Повний текст джерелаSwezey, Daniel Sergio. "Ocean Acidification on the California Coast| Responses of Marine Bryozoa to a High CO2 Future." Thesis, University of California, Davis, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10036209.
Повний текст джерелаAs a result of human activities, the level of CO2 in the Earth’s atmosphere has increased by nearly 40% since the industrial revolution. The rate of green house gas emission is accelerating, with current trends exceeding those predicted by “worst case” global climate change scenarios. The chemistry of the ocean is fundamentally changing as a result of increasing atmospheric CO2, which dissolves in seawater, making it more acidic, a process referred to as ocean acidification (OA). A rapidly expanding body of science is now being generated to understand the impact of this global environmental change. To date, most studies evaluating OA effects have centered on simplified laboratory analyses that expose single populations to short-term treatments in order to quantify responses of individuals. These designs offer a limited assessment of the degree to which phenotypic plasticity and local adaptation might influence the response of populations to OA.
To address these questions, I carried out studies on members of Phylum Bryozoa, a species-rich clade of calcified colonial marine invertebrates distributed throughout the global ocean. Bryozoans were selected as a model system for this work because the clade exhibits a broad array of growth and calcification strategies, and because of the relative paucity of data regarding their expected response to future acidification. In addition, bryozoans can be subdivided into genetically identical replicate clones, which can then be assigned to separate treatments, allowing variation across treatments to be uniquely partitioned into the variance components of statistical models. In order to culture bryozoans for comparative experiments, I designed and constructed a new flow-through OA system at the Bodega Marine Laboratory, capable of finely manipulating both the temperature and carbonate chemistry of seawater, allowing for controlled laboratory experiments of long duration.
In Chapter 1, I performed a comparative 9-month laboratory experiment examining the effects of ocean acidification on the native Californian bryozoan Celleporella cornuta. C. cornuta was sampled from two regions of coastline that experience different oceanographic conditions associated with variation in the intensity of coastal upwelling. Under different CO2 treatments, the biology of this bryozoan was observed to be remarkably plastic. Colonies raised under high CO2 grew more quickly, invested less in reproduction, and produced skeletons that were lighter compared to genetically identical clones raised under current atmospheric values. Bryozoans held in high CO2 conditions reduced their investment in skeletal carbonate, changed the Mg/Ca ratio of skeletal walls and increased the expression of organic coverings that may serve a protective function. Differences between populations in growth, reproductive investment, and the frequency of organic covering production were consistent with adaptive responses to persistent variation in local oceanographic conditions.
In Chapter 2, I tested whether skeletal mineralogy can vary plastically in some invertebrates using the cosmopolitan bryozoan Membranipora tuberculata as a model. In a 6-month laboratory experiment, I cultured genetic clones of M. tuberculata under a factorial design with varying food availability, temperature, and dissolved CO2 concentrations. Elevated food availability increased growth in colonies while cold temperatures and high CO2 induced degeneration of colony zooids. However, colonies were able to maintain equivalent growth efficiencies under cold, high CO2 conditions, suggesting a compensatory tradeoff whereby colonies increase the degeneration of older zooids under adverse conditions, redirecting this energy to the maintenance of growth. Elevated food and cold temperatures also decreased Mg concentrations in skeletal material, and this skeletal material dissolved less readily under high CO2 conditions. This suggests that these factors interact synergistically to affect dissolution potential in this and other species.
Finally, in Chapter 3, I explore stable isotope values for δ 18O and δ13C in the calcium carbonate structures of the bryozoan Membranipora tuberculata. I tested whether this species accurately records both temperature and pH variability during periods of coastal upwelling by analyzing δ18O and δ 13C in colonies grown in the field and in controlled laboratory cultures. Field-grown colonies were out planted next to a Durafet® pH sensor, which provided a high-resolution record of the temperature and pH conditions these colonies experienced. δ13C was found to negatively co-vary with pH in both laboratory and field growth, and calculated field temperatures derived from laboratory δ18O temperature calibrations aligned with the records from the pH sensor. δ18 Oc values were more depleted under low pH in laboratory trials, which stands in contrast to patterns observed in other taxa. This may indicate that Membranipora utilizes bicarbonate ion (HCO 3-) in its calcification pathway, and could help explain why many bryozoan species appear to exhibit enhanced growth under high CO 2 conditions. (Abstract shortened by ProQuest.)
Maran, Audrey M. "Predator Contributions to Belowground Responses to Warming." Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1434114404.
Повний текст джерелаKornder, Niklas Alexander. "Using Regression-Based Effect Size Meta-Analysis to Investigate Coral Responses to Climate Change." NSUWorks, 2016. http://nsuworks.nova.edu/occ_stuetd/415.
Повний текст джерелаBögelein, Sandra. "The social dilemma structure of climate change mitigation : individual responses and effects on action." Thesis, University of East Anglia, 2015. https://ueaeprints.uea.ac.uk/61370/.
Повний текст джерела