Rozprawy doktorskie na temat „Biogeochemical modelling”
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Rushby, Andrew. "Modelling biogeochemical controls on planetary habitability". Thesis, University of East Anglia, 2015. https://ueaeprints.uea.ac.uk/58503/.
Pełny tekst źródłaRocha, Carlos Rafael Vieira. "Biogeochemical modelling of the NW Iberian Margin". Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/9576.
Pełny tekst źródłaA capacidade de fornecer dados oceanográficos sobre variáveis biológicas e químicas tem-se tornado num tema de relevância científica nos últimos anos. A procura por este tipo de informação provém de áreas e aplicações tão diversas como a investigação em ecossistemas marinhos, a monitorização da qualidade da água e o suporte à gestão do ambiente marinho e costeiro. Este trabalho consiste numa visão geral sobre a incorporação de um módulo biogeoquímico baseado em fluxos de azoto (NPZD) num modelo de circulação oceânica regional (ROMS) para a Margem NW Ibérica e para o período de 2007 a 2010. O estudo foca-se especialmente na validação do modelo, tanto empírica como objectiva, através da comparação entre os valores de clorofila-a simulados e os que constam numa extensa base de dados produzida pelo Ifremer/CERSAT, assim como na verificação da capacidade de reprodução de alguns fenómenos teoricamente expectáveis. A validação do modelo mostra que, embora existam algumas falhas, como uma subestimação geral dos valores superficiais de clorofila-a ou a antecipação ao início dos blooms primaveris, a resposta deste é satisfatória. Embora ainda exista muito a melhorar, é possível afirmar que está criado um modelo com acoplamento biogeoquímica-hidrodinâmica, completamente funcional e credível, com capacidade de simulação a uma escala inter-anual para a Margem NW Ibérica.
Providing oceanographic data on biological and chemical variables has become an issue of scientific concern over the last years. The demand for this kind of information arises from a range of fields and applications such as scientific research on marine ecosystems, monitoring of seawater quality and decision-making support for marine and coastal management. This work consists of an overview on the incorporation of a nitrogen-based (NPZD) biogeochemical module into a regional oceanic circulation model (ROMS) for the NW Iberian Margin for the 2007 to 2010 period. The study focuses especially in both empirical and objective model performance assessments through comparison of chlorophyll-a model outputs with an extensive satellite dataset produced by Ifremer/CERSAT and in the verification of the model ability to reproduce theoretically expected phenomena. The model validation shows that despite some flaws, as a general underestimation of chlorophyll-a surface values and an anticipation in the starting of the spring bloom, the model response is satisfactory. With still much to improve, its however possible to state that a fully-functional and reliable coupled biogeochemicalocean circulation model is available for the NW Iberian Margin, running at the inter-annual scale.
Manizza, Manfredi. "Modelling phytoplankton-light feedback and its ocean biogeochemical implications". Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429677.
Pełny tekst źródłaTedesco, Letizia <1978>. "Modelling coupled physical-biogeochemical processes in ice-covered oceans". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1996/1/letizia_tedesco_phd_thesis.pdf.
Pełny tekst źródłaTedesco, Letizia <1978>. "Modelling coupled physical-biogeochemical processes in ice-covered oceans". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1996/.
Pełny tekst źródłaBagnara, Maurizio <1985>. "Modelling biogeochemical cycles in forest ecosystems: a Bayesian approach". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7188/1/Bagnara_Maurizio_tesi.pdf.
Pełny tekst źródłaBagnara, Maurizio <1985>. "Modelling biogeochemical cycles in forest ecosystems: a Bayesian approach". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7188/.
Pełny tekst źródłaLongo, Ana Rita Sá. "Biogeochemical response of Tagus Estuary to climate change : a modelling study". Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15740.
Pełny tekst źródłaEstuaries are highly dynamic systems which may be modified in a climate change context. These changes can affect the biogeochemical cycles. Among the major impacts of climate change, the increasing rainfall events and sea level rise can be considered. This study aims to research the impact of those events in biogeochemical dynamics in the Tagus Estuary, which is the largest and most important estuary along the Portuguese coast. In this context a 2D biophysical model (MOHID) was implemented, validated and explored, through comparison with in-situ data. In order to study the impact of extreme rainfall events, which can be characterized by an high increase in freshwater inflow, three scenarios were set by changing the inputs from the main tributaries, Tagus and Sorraia Rivers. A realistic scenario considering one day of Tagus and Sorraia River extreme discharge, a scenario considering one day of single extreme discharge of the Tagus River and finally one considering the extreme runoff just from Sorraia River. For the mean sea level rise, two scenarios were also established. The first with the actual mean sea level value and the second considering an increase of 0.42 m. For the extreme rainfall events simulations, the results suggest that the biogeochemical characteristics of the Tagus Estuary are mainly influenced by Tagus River discharge. For sea level rise scenario, the results suggest a dilution in nutrient concentrations and an increase in Chl-a in specific areas.For both scenarios, the suggested increase in Chl-a concentration for specific estuarine areas, under the tested scenarios, can lead to events that promote an abnormal growth of phytoplankton (blooms) causing the water quality to drop and the estuary to face severe quality issues risking all the activities that depend on it.
Os estuários são sistemas altamente dinâmicos que se encontram em risco devido a eventos relacionados com as alterações climáticas. Estas alterações podem ter impactos nos ciclos biogeoquímicos. Entre esses efeitos podem considerar-se o aumento de períodos de chuvas torrenciais e o aumento do nível médio do mar. Assim, o objetivo deste trabalho é o estudo do impacto destes eventos na dinâmica biogeoquímica do Estuário do Tejo, que se trata do maior sistema estuarino da Península Ibérica. Neste contexto, foi implementado, validado e explorado através de comparação com dados in-situ, um modelo biofísico 2D (MOHID). De forma a avaliar a resposta biogeoquímica do estuário a períodos de chuvas torrenciais, caracterizadas por variações abruptas nas descargas fluviais dos principais tributários, Tejo e Sorraia, foram considerados três cenários. O primeiro considerando um dia de descarga extrema para os rios Tejo e Sorraia. O segundo, considerando uma descarga extrema apenas para o Rio Tejo e por último, considerando uma descarga apenas para o Rio Sorraia. Relativamente ao aumento do nível médio do mar, foram estabelecidos dois cenários, o primeiro com o nível médio do mar atual e o segundo considerando um aumento de 0.42 m, conforme estimado em estudos anteriores. Os resultados para a simulação das chuvas torrenciais indicam que as modificações previstas para os padrões biogeoquímicos dependem essencialmente da descarga do Rio Tejo. Para o cenário de aumento do nível médio do mar os resultados sugerem uma diminuição da concentração de nutrientes e um aumento de clorofila em áreas específicas. Em ambos os cenários, o aumento de clorofila em determinadas zonas do estuário, sugerido pelos resultados, pode levar a eventos que promovam um crescimento anormal de fitoplâncton fazendo com que a qualidade da água diminua e colocando em risco todas as atividades que dependem no Estuário do Tejo.
Everett, Jason D. School of Biological Earth & Environmental Science UNSW. "Biogeochemical dynamics of an intermittently open estuary: a field and modelling study". Awarded by:University of New South Wales. School of Biological, Earth and Environmental Science, 2007. http://handle.unsw.edu.au/1959.4/30555.
Pełny tekst źródłaCropp, Roger Allan, i R. Cropp@griffith edu au. "A Biogeochemical Modelling Analysis of the Potential For Marine Ecosystems to Regulate Climate By the Production of Dimethylsulphide". Griffith University. Australian School of Environmental Studies, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030703.101310.
Pełny tekst źródłaCropp, Roger Allan. "A Biogeochemical Modelling Analysis of the Potential For Marine Ecosystems to Regulate Climate By the Production of Dimethylsulphide". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367734.
Pełny tekst źródłaThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
Full Text
McEwan, Robert. "Interdisciplinary study of hydrodynamic and biogeochemical processes of a large-scale river plume". Thesis, University of Plymouth, 2013. http://hdl.handle.net/10026.1/1551.
Pełny tekst źródłaHutton, Christopher. "Modelling the biogeochemical mobility of arsenic : a case study of Roseworthy, Cornwall, UK". Thesis, University of Exeter, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430564.
Pełny tekst źródłaRicci, Giovanni. "Organic matter deposition/resuspension in a one-dimensional physical-biogeochemical model. A modelling study". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10595/.
Pełny tekst źródłaNickelsen, Levin [Verfasser]. "Modelling the marine biogeochemical implications of aeolian, sedimentary and riverine iron supply / Levin Nickelsen". Kiel : Universitätsbibliothek Kiel, 2015. http://d-nb.info/1072621452/34.
Pełny tekst źródłaJones, Emlyn Morris, i emlyn jones@csiro au. "The interaction between physical and sedimentary biogeochemical processes in south-west Spencer Gulf, South Australia". Flinders University. School of the Environment, 2010. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20100531.124356.
Pełny tekst źródłaPorada, Philipp [Verfasser]. "Process-based modelling of lichens and bryophytes and their role in global biogeochemical cycles / Philipp Porada". Mainz : Universitätsbibliothek Mainz, 2014. http://d-nb.info/1047249944/34.
Pełny tekst źródłaSerpetti, Natalia. "Modelling and mapping the physical and biogeochemical properties of sediments on the North Sea coastal waters". Thesis, University of Aberdeen, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553875.
Pełny tekst źródłaRen, Ling. "Biogeochemical conversion of nitrogen in enclosed pelagic coastal ecosystems of the German Bight mesocosm and modelling studies /". [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965393666.
Pełny tekst źródłaMårtensson, Sebastian. "Ridged sea ice modelling in climate applications". Doctoral thesis, Stockholms universitet, Meteorologiska institutionen (MISU), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93977.
Pełny tekst źródłaAt the time of the doctoral defence the following paper was unpublished and had a status as follows: Paper 4: Manuscript
Dessirier, Benoît, i Safeyeh Soltani. "Dynamics of internal nutrient sources in the Baltic Sea - A comparative modelling study of the Gulf of Finland". Thesis, KTH, Vattenvårdsteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96110.
Pełny tekst źródłaHelliwell, R. C. "Biogeochemical modelling of acid sensitive systems in Scotland : influence of scale and the potential role of enhanced nitrogen deposition". Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.592556.
Pełny tekst źródłaKelly-Gerreyn, Boris Adrian. "Modelling sedimentary biogeochemical processes in a high nitrate, UK estuary (the Gt. Ouse) with emphasis on the nitrogen cycle". Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273834.
Pełny tekst źródłaHommel, Johannes [Verfasser], i Holger [Akademischer Betreuer] Class. "Modelling biogeochemical and mass transport processes in the subsurface : investigation of microbially induced calcite precipitation / Johannes Hommel ; Betreuer: Holger Class". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2016. http://d-nb.info/1118369602/34.
Pełny tekst źródłaPalmiéri, Julien. "Modélisation biogéochimique de la mer Méditerranée avec le modèle régional couplé NEMO-MED12/PISCES". Thesis, Versailles-St Quentin en Yvelines, 2014. http://www.theses.fr/2014VERS0061/document.
Pełny tekst źródłaThe Mediterranean Sea is considered as a hot spot of climate change. This arid region, already under high anthropogenic influence, is said to become even warmer and drier, with still an increasing anthropogenic pressure. In this context, numerous physical and biogeochemical data are currently collected in the Mediterranean Sea, within the MERMEX project, enabling to better study and understand the Mediterranean biogeochemical cycles. Complementary to in-situ observations, modelling is an unique tool that helps to understand and quantify biogeochemical controling processes in the Mediterranean Sea, its specificity, and its evolution. In this study, we propose the setting and evaluation of a regional, high resolution, marine dynamicalbiogeochemical coupled model (NEMO-PISCES). It will be the first model available for the MERMEX community, that covers the whole Mediterranean Sea. Therefor, after the evaluation of NEMO-MED12 dynamical forcing fields, within passive tracers simulation (CFC), firsts use of this tool have been made : (i) we have evaluated anthropogenic carbon uptake and induced acidification of the Mediterranean Sea, within a perturbation approach ; (ii) we have analysed Mediterranean Sea trophic regimes, as represented by the model, for different layers of the photic zone
Ma, Yamin. "Vegetation as a biotic driver for the formation of soil geochemical anomalies for mineral exploration of covered terranes". University of Western Australia. School of Earth and Geographical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0235.
Pełny tekst źródłaRodríguez-Escales, Paula F. "Modeling of enhanced in situ biodenitrification at different scales: Integration of microbiological, hydrogeochemical, and isotope biogeochemical processes". Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/284930.
Pełny tekst źródłaIn this thesis, an integrated reactive transport model has been developed that takes into account microbiology, geochemistry, and isotope geochemistry. The first section of the thesis (Chapter 2) addresses the development of a biogeochemical model with isotope geochemistry. The goal of this chapter is the setup of the conceptual relationships among microbiology, geochemistry, and isotope geochemistry (δ15N-NO3-, δ18O-NO3-, δ13C-DIC, and all geochemistry of δ13C) during Enhanced in situ Biodenitrification. Thus, one of the most complete biogeochemical models in the literature of EIB has been developed. The model was validated with a batch-scale biodenitrification experiment using groundwater and sediment from a Roda de Ter (Osona, Spain) site and two different external organic carbon sources, i.e., ethanol and glucose. In both cases, the model fit notably well with the experimental data. Moreover, the developed model also incorporated the nitrite accumulation observed in the glucose experiment. Consideration of the water-rock interaction in the model determined that if ethanol is used as an organic carbon source, carbonate mineral precipitation is induced, whereas if glucose is used, carbonate mineral dissolution is observed. Moreover, nitrate isotope incorporation facilitated the determination of the extent of denitrification at the field scale. Finally, the incorporation of a carbon isotope flow in the model was another tool used to verify the full consistence of the model due to the central role of inorganic carbon in biodenitrification and water-rock interactions. Moreover, modeling of carbon isotope flow showed that both ethanol and glucose were inversely fractionated. After the conceptual model was carried out, it was applied to an Enhanced in situ Biodenitrification application in fractured media (also Roda de Ter (Spain)). The main goal of this chapter is to incorporate the groundwater flow equations into a previously develop biogeochemical model and to validate it in media with a complex hydrogeology. It was observed that certain batch parameters can be used directly in the field (maximum consumption rate of electron donor (kmax) and stoichiometric relationships) and that the other parameters (saturation constants (Ks) and decay (b)) should be adapted, but the modifications involved less than one order of magnitude. Moreover, the induced calcite precipitation caused a change of porosity of less than 3%. As a secondary goal, the use of the Rayleigh equation to determine the extent of EIB was also verified from a practical perspective. The model demonstrated that the Rayleigh equation underestimated the percentage of degradation by approximately 60-80% and increasingly at the fringes of the plume. Chapter 4 focuses on a model that reproduces the system under different injection conditions and with the presence of important biofilm growth. This chapter evaluates how different feeding strategies modify the hydraulic properties of the media. It was observed that a weekly feeding strategy did not modify the hydraulic properties of the media, whereas daily feeding significantly modified the dispersivity. These changes in dispersivity implied an increase in heterogeneity and a consequent change in the conceptual model of flow transport along the column from normal to non-Fickian. This transition was well characterized using a single-rate mass transfer model. Moreover, the long-term model demonstrated that use of a feeding strategy with less carbon than predicted by stoichiometry implied a reduction of biomass without a reduction in nitrate degradation rates (because of the presence of an important biomass population). Overall, the elaboration of this thesis has contributed to the knowledge of all processes involved in Enhanced in situ Biodenitrification and their quantification using numerical models. The developed model will allow improvement in the design, planning, monitoring and optimization of this technology at the field scale.
Campbell, Rose. "Tourbillons anticycloniques dans le golfe du Lion : Modélisation couplée physique-biogéochimique". Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4118.
Pełny tekst źródłaThe role that mesoscale physical structures play in driving plankton community shifts and transporting matter is key to the understanding of food web dynamics at the regional scale
Quilcaille, Yann. "Retour sur les scénarios climatiques et d'émissions à l'aide d'un modèle compact du système Terre". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLV041/document.
Pełny tekst źródłaThis thesis puts into perspective different elements of socio-economic scenarios from a climate change modelling point of view. These elements contribute at improving the comprehension of the current state of climate sciences regarding the scenarios. In the meantime, these elements demonstrate the potential of the recent reduced-form Earth System Model OSCAR v2.2.The first element concerns the uncertainty of emissions. Although emission inventories are uncertain, we ignore what impact on climate change have these uncertainties. We quantify this impact for fossil-fuel emissions, the major contributor to climate change. We show that the uncertainties in emissions are expected to increase with the use of non-conventional fuels, but that they do not increase significantly the uncertainty from Earth system modelling in variables, such as the increase in global surface temperature.The second element is a climate assessment of the recent Shared Socio-economic Pathways (SSP) scenarios. We identify loopholes in the SSP database, and we complete it to calculate the climate projections under these scenarios. Our conclusions suggest inconsistencies in CO2 emissions from Land Use Change (LUC) calculated by the Integrated Assessment Models and in the associated land variables. We identify trade-offs between greenhouse gases in the mitigation of climate change. Using a robust assessment, new carbon budgets are proposed. The uncertainties in increases in global surface temperature are discussed.The third element concerns the negative emissions. Most climate scenarios limiting global warming well below 2°C above preindustrial levels, thus respecting the Paris Agreement, use negative emissions. Using a developed version of OSCAR v2.2, we evaluate the implications for the Earth system of different aspects of different Carbon Dioxide Removal (CDR) technologies. We identify the reversibility in the different components of the Earth system and calculate the cooling potential of carbon dioxide removal technologies. We also show that the potential of afforestation/reforestation techniques may be impeded by the change in albedo, and that the potential of oceanic enhanced weathering may be lower than expected.Overall, this thesis identifies loopholes in the current development of scenarios. Some do not hinder current conclusions regarding climate change, such as the uncertainties in emission inventories. Others call for further analysis, such as the inconsistencies in the use of CO2 emissions from LUC or the eventual overestimation of the potential of some CDR technologies. It emphasizes the need for an urgent mitigation of climate change
Ayache, Mohamed. "Modélisation d’éléments traces (T, 3He, Nd, 14C) en mer Méditerranée pour l’étude des cycles biogéochimiques et de la circulation océanique". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV138/document.
Pełny tekst źródłaUseful diagnostics of the ventilation of the ocean’s interior are derived from geochemical tracers characterized by simple boundary conditions at the ocean’s surface, and a conservative behavior in marine waters. In this thesis, we simulated explicitly some trace elements distribution in the Mediterranean to better constrain the thermohaline circulation and biogeochemical cycles. We used a high resolution physical/biogeochemical model NEMO-MED12-PISCES.The Mediterranean offers a particularly attractive setting for studying geochemical tracers. It’s a semi-enclosed basin, which makes it easier to quantify the various sources and sinks of the elements (atmospheric dust, rivers ...). In particular, we modeled tritium (3H), a transient tracer currently used for the study of the interannual variability of the thermohaline circulation. We also simulated helium isotopes (3He, 4He), useful tracers for investigating the deep ocean circulation.We have simulated the isotopic composition of neodymium (Nd), tracer adapted to investigate the exchanges between dissolved/particulate phases, with the continental margins, and to constrain the modern and paleo thermohaline circulation, as well as radiocarbon (14C), an ideal tracer for studying air-sea gas exchange and for assessing the ventilation rate of the deep water masses over very long timescales.This study is part of the work carried out to assess the robustness of the NEMO-MED12 model, which will be used to study the evolution of the climate and its effect on the biogeochemical cycles in the Mediterranean Sea, and to improve our ability to predict the future evolution of the Mediterranean Sea under the increasing anthropogenic pressure
Fink, Daniel Francis. "Effects of a pulsing hydroperiod on a created riparian river diversion wetland". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1167401886.
Pełny tekst źródłaDemestihas, Constance. "Analyse des conflits et synergies entre services écosystémiques multiples en vergers de pommiers". Thesis, Avignon, 2017. http://www.theses.fr/2017AVIG0690/document.
Pełny tekst źródłaThe concept of « ecosystem service », which has been used increasingly since the publication of the Millennium Ecosystem Assessment in 2005, has highlighted the importance of ecosystem’s non-marketed performances. In orchards, ensuring high productivity while preserving natural resources and human health has become a real challenge that could be analyzed with the concept of ecosystem service. Which ecosystem services are delivered in an apple orchard? How to analyze them? What are the relationships - conflicts or synergies – among multiple ecosystem services and how do cropping systems change multiple ecosystem service profiles? This PhD work aims at answering those questions with an innovative approach combining experimental measures, modeling and statistical analysis.Based on a literature review of ecosystem services in orchards, five services were selected: fruit production, nitrogen availability in soil, climate regulation based on the prevention of nitrogen denitrification and on carbon sequestration, maintenance and regulation of water cycle, including water quality, and pest control. We also considered the environmental disturbances caused by the use of pesticides. For each service, we identified the underlying ecosystem functions as well as the agricultural practices and soil and climate conditions affecting these functions. Services and functions were described by one or multiple indicators and quantified using models in the case of (i) nine existing cropping systems on two experimental sites in southeastern France differing in terms of soil and climate conditions, and (ii) 150 virtual cropping systems designed out of the combination of five major agricultural practice levers and their modalities, in identical soil and climate conditions. The two models used were STICS, a generic soil-crop simulation model under the influence of practices which required a parameterization and an evaluation on apple orchards based on experimental measures, and IPSIM, a generic modeling framework simulating the impacts of agricultural practices and local conditions on crop injuries caused by pests. IPSIM was parameterized on apple orchards, based on an important literature review and expert opinions. Model simulations were analyzed with simple statistics in the case of the nine existing cropping systems and with two-table multivariate analyses (principal component analysis with instrumental variables) for virtual cropping systems.Concerning the existing cropping systems, 14 important relationships were identified among ecosystem services, especially conflicts, like the one between nitrogen denitrification or leaching prevention and soil nitrogen availability on the short term, and synergies such as the one between soil humidity or carbon sequestration and nitrogen availability on the short term. These relationships are explained by the underlying ecosystem functions. Comparing service profiles among cropping systems highlighted the impacts of agricultural practices on some services. That way, on a same site, a high planting density increases fruit production and carbon sequestration. An exclusively organic fertilization decreases fruit production through nitrogen stress but also nitrogen leaching in drained water. Furthermore, service profiles are strongly influenced by the soil and climate conditions of each site. These results strengthen the need to explicitly consider the ‘agricultural practices x soil and climate conditions’ interdependence in order to analyze ecosystem services. The results obtained with the virtual cropping systems simulations confirmed those of the existing ones and gave precision on the impacts of fertilization, irrigation and pest control for codling moth, rosy apple aphid and apple scab on ecosystem functions and services
Minaudo, Camille. "Analyse et modélisation de l'eutrophisation de la Loire". Thesis, Tours, 2015. http://www.theses.fr/2015TOUR4047/document.
Pełny tekst źródłaThis thesis aims at studying the physical and chemical causes and consequences that result from excessive phytoplankton growth in the Loire River. The analysis identified some parameters characterizing river eutrophication and was conducted on several spatial and temporal scales. This was based on long-term water quality time-series (1980-2012), a daily survey carried out during this work (2012-2014), and the numerical modeling of the river biogeochemical functioning with an hourly resolution. Phytoplankton development in summer was reduced 2.5-fold in the Loire River and in the main tributaries, synchronously with the generalized reduction 3-fold of bioavailable phosphorus as a result of controlling and limiting phosphorus point sources. However, the Loire River remains sensitive to eutrophication, with a significant urban and agricultural pressure, low water levels in summer, and its multiple channels morphology slowing down the water velocity. All these factors combined favor phytoplankton development. When hydrological conditions are favorable, phytoplankton grows and significantly affects the ecosystem functioning, with an impact on nutrients, carbon and oxygen biogeochemical cycles
Bouza, Rosa Reboreda. "Modelling the biogeochemical dynamics of the iberian upwelling system". Doctoral thesis, 2013. https://repositorio-aberto.up.pt/handle/10216/84701.
Pełny tekst źródłaBouza, Rosa Reboreda. "Modelling the biogeochemical dynamics of the iberian upwelling system". Tese, 2013. https://repositorio-aberto.up.pt/handle/10216/84701.
Pełny tekst źródłaHadley, SA. "Farming macroalgae to mitigate coastal nutrification from finfish aquaculture : a modelling study". Thesis, 2015. https://eprints.utas.edu.au/23177/1/Hadley_whole_thesis.pdf.
Pełny tekst źródłaSinoir, M. "Zinc biogeochemical cycle in the Tasman Sea : potential role for phytoplankton communities". Thesis, 2013. https://eprints.utas.edu.au/17143/3/whole-Senoir-thesis-inc-pub-mat.pdf.
Pełny tekst źródłaRen, Ling [Verfasser]. "Biogeochemical conversion of nitrogen in enclosed pelagic coastal ecosystems of the German Bight : mesocosm and modelling studies / vorgelegt von Ling Ren". 2002. http://d-nb.info/965393666/34.
Pełny tekst źródłaBianucci, Laura. "Carbon, oxygen, and nitrogen cycles on the Vancouver Island shelf". Thesis, 2010. http://hdl.handle.net/1828/2995.
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