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Дегтярьова, Ія Олександрівна, Ия Александровна Дегтярева, Iia Oleksandrivna Dehtiarova, and D. Snitko. "Ecological-economic systems efficiency." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/7833.
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Milner, Rebecca J. "Ecological Systems in Action." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/2977.
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Book Summary: The Handbook of Experiential Teaching in Counselor Education: A Resource Guide for Counselor Educators is a peer-reviewed guide for teaching CACREP related course content. With 20 chapters covering multiple aspects of the CACREP standards, counselor educators have shared their resources, tips, and classroom techniques for training the next generation of counselors.
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Дегтярьова, Ірина Борисівна, Ирина Борисовна Дегтярева, and Iryna Borysivna Dehtiarova. "Synergism of ecological-economic systems." Thesis, Вид-во СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/8090.
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Lascoutx, Ruiz Alfredo. "A Politico-Ecological Approach of Transitional Spaces In Social Ecological Systems." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/41987.
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As spatial properties that systems theoretically have, Socio-Ecological Systems are characterized by dynamism and mobility, therefore, are subject to changes in the space they occupy in the biosphere. In land ecosystems, these changes are understood as processes of evolution over time, or the result of extreme natural events, or transformation of the natural space induced by human activities.
These spatial changes produce effects on the land surface and groundwater of ecosystems colonized or penetrated by elements, individuals or populations belonging to other ecosystems. These are the so-called Transitional Spaces between ecosystems.
Throughout the continuous geographical space, these spatial transitions affect human and not human ecosystems in different ways. Given their ambiguous characteristics and their indefinite temporal location between urban, rural or natural spaces, transition spaces deserve to be investigated in order to know their properties and functions within the cartography that represents complex socio-ecological systems.
The research is conducted from a particular perspective of Political Ecology. For this I proceed to develop an epistemological exercise on the political ecology syntagma in order to approach its concept and object of study as a hybrid discipline between social sciences and natural sciences. Interdisciplinarity as a practice, a dialectic vision regarding anthropocentrism, environmental perception as a method for an ontology of human ecology, The ecosystem as a unit of spatial analysis. These would be some of the characteristics of my ecological-political perspective.
But what does transitional space mean for political ecology and what does it add to its theory? The question led me to seek the integral concept of ecosystem and to support myself in the General Systems Theory to analyze the notions of boundary and external environment as part of the classic concept of system. At that point, the notion of transitional spaces emerges implicit when recognizing the dynamic spatiality of other existing systems.
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Since the research is not linear but interdisciplinary and convergent, a brief anthology of geographic and socio-spatial political thought is presented in order to connect the issue of transitional spaces with the point of view of the social sciences. Various socio-geographical, deterministic, anthropocentric, Darwinian, Marxist, modernist theories give an overview of the issues related to space and nature. With the emergence of the spatial turn, new concerns for political sociology, geography and environmental sciences are explained by the phenomenon of urban growth at the global level.
In the same way, I introduce the topic of ecological spaces, specifically the concept of Ecotone, the space of transition between diverse natural ecosystems. The use of the notion of ecotone is based precisely on the perspective of the concept of political ecology developed previously.
This, in turn, will allow me to introduce the FLACAM methodology into the research, which among its components has the virtue of identifying and analyzing the spatial phenomenon of physical and social Interfaces, that is, spaces of transition within human ecosystems. Several graphics and charts show the potential properties and functions of different kind of existing interfaces and ecotones. My proposal converges in using these concepts as planning tools for transitional spaces identified as Rurban Regions and metropolitan areas.
A final reflection on the need for spatial research on global urban expansion and the theoretical and pragmatic advantages of the concept of intermediate cities closes the main body of the investigation.
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Мельник, Леонід Григорович, Леонид Григорьевич Мельник, Leonid Hryhorovych Melnyk, Ірина Борисівна Дегтярьова, Ирина Борисовна Дегтярева, and Iryna Borysivna Dehtiarova. "Synergetic effects of ecological-economic systems." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/7920.
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Modern character of ecological-economic relations needs new approaches to long-term and short-term strategies of territorial development. For ecological-economic efficiency we need to incorporate not only internal results of economic subjects, but also external results, that appear as a result of economic subject’s activity in other spheres.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/7920
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Lopes, Marta Filipa Lobão. "Ecological quality assessment in transitional systems." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14856.
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Doutoramento em BiologiaEstuaries are poles of attraction for human settlement which is a source of pressures to surface water bodies. The implementation of the European Water Framework Directive (WDF, 2000/60/EC) has increased the investigation in order to develop methodologies to assess the Ecological Quality Status (EQS) of aquatic ecosystems. Transitional systems are naturally stressed and characterized by highly dynamic physical, chemical and hydro-morphologic conditions and by species with a higher level of tolerance to change, being more difficult to develop suitable quality indicators for these systems. The general purpose of this study is to test the ability of synthesis descriptors, including primary (S, taxa richness) and derived biological variable (H’, Shannon-Wiener diversity), biotic indices (AMBI and M-AMBI), body size properties (abundance distribution by body size classes, length, weight and length-weight relationships) and non-taxonomic indices (ISS), as well as functional indicators related to the decomposition rates of various experimental substrates, a macrophyte (Phragmites australis) and an alga (Fucus vesiculosus), to evaluate the environmental quality in transitional systems. This study was carried out in one of the most pristine channels of the Ria the Aveiro, Mira Channel, along a full salinity gradient and in a metals and metalloid sediment contamination area, the Estarreja Channel, and two reference channels (Canelas and Salreu). In this study were used different sampling techniques, the leaf-bag technique and a hand-held corer. In Mira Channel, the alga and the macrophyte presented an opposite trend in the decomposition rate along the salinity gradient, with the decomposition rates of the alga always higher than those of the macrophyte. The decomposition rates of the macrophyte and the alga were higher in the mid estuary and in higher salinity areas, respectively, corresponding to the preferencial distribution areas of each species. The macrobenthic fauna associated with the decaying and an artificial substrate (control) showed equally well the benthic succession from the marine to the freshwater areas and, despite the strong differences in the decay rates, no significant differences were found between the benthic communities associated with the alga and the macrophyte. The body size properties of the macrobenthic fauna associated with the P. australis leaf-bag (1mm and 5mm) and corer samples were studied along the full salinity gradient. The dominant species of the sub-set of measured specimens were not the same of the original macrobenthic fauna sampled but, despite that, the sub-set of measured specimens was also able to show the benthic succession from the marine to the freshwater areas. The body size abundance distribution of the benthic macroinvertebrates according to the ISS size classes did not show a particular trend in any sampler along the salinity gradient. Significant differences were found in the length, weight and length-weight relationships of Annelids, , Molluscs and even some species along the salinity gradient. No significant differences were found in the AMBI, M-AMBI and ISS values along the salinity gradient for all the samplers. The EQS of the corer samples obtained using the M-AMBI was lower than that of the leaf-bags. The EQS obtained with the ISS was higher than that obtained with the M-AMBI in the leaf-bags but not in the corer samples. The ecological effects of contaminated sediments associated with the industrial chemical effluents discharged in the Estarreja Channel were studied a decade after ceasing the emissions, using the Sediment Quality Triad approach and two reference channels. The results showed that despite the emissions ceased in 2004, the sediment remains polluted with high levels of metals and metalloid, available to bioaccumulation and with severe consequences at the community level. The sediment contamination problem was also studied using the leaf-bag technique with a macrophyte, an alga and a control substrate. The results showed that the decay rates, the associated macrofauna and the application of the AMBI, M-AMBI and ISS indices to the mesh-bag samples were not able to identify the sediment contamination. Contrarily to the AMBI, the M-AMBI and the ISS showed significant differences between the contaminated and the reference channels for the corer samples. Although such statistical significance, the interest of using these complex biotic indices could be questioned, when much simple ones, like the S and H’ allow to reach the same conclusions.
Os estuários são pólos de atração para a instalação de aglomerados humanos, constituindo uma fonte de pressão para as massas de água superficiais. Com a implementação da Diretiva Europeia Quadro da Água (DQA, 2000/60/CE) tem aumentado a investigação no sentido de desenvolver metodologias para avaliar o estado de qualidade ecológica (EQE) dos ecossistemas aquáticos. Os sistemas de transição são caracterizados por condições físico-químicas e hidromorfológicas extremamente dinâmicas e por espécies com uma maior tolerância à mudança, sendo difícil desenvolver indicadores de qualidade adequados para estes ecossistemas. O objetivo deste estudo é testar a capacidade de descritores de síntese, tais como a riqueza em espécies (S) e a diversidade de Shannon-Wiener (H'), índices de base taxonómica (AMBI e M-AMBI) e não taxonómica (ISS), as propriedades do tamanho corporal (distribuição de abundância por classes de tamanho corporal, comprimento, peso e relações comprimento-peso), bem como indicadores funcionais (taxas de decomposição de uma macrófita (Phragmites australis) e uma alga (Fucus vesiculosus)), para avaliar a qualidade ambiental dos sistemas de transição. Este estudo foi realizado ao longo de um gradiente completo de salinidade num dos canais com menor impacto antropogénico da Ria de Aveiro, o Canal de Mira, numa área com contaminação sedimentar por metais e metaloides, o Canal de Estarreja, e dois canais de referência (Canelas e Salreu). Neste estudo foram utilizadas diferentes técnicas de amostragem, a técnica dos sacos de folha e corers. No Canal de Mira, a alga e a macrófita apresentaram uma tendência oposta na taxa de decomposição ao longo do gradiente de salinidade, com as taxas de decomposição da alga sempre superiores. As taxas de decomposição da macrófita e da alga foram mais elevadas a meio do estuário e em áreas de maior salinidade, respetivamente, correspondendo às preferenciais áreas de distribuição de cada espécie. A fauna bentónica associada aos substratos orgânicos e a um substrato artificial (controlo) mostrou a sucessão bentónica ao longo do gradiente estuarino e, apesar das grandes diferenças nas taxas de decomposição, não foram encontradas diferenças nas comunidades bentónicas entre ambos os substratos. As propriedades do tamanho corporal da fauna bentónica dos sacos de folhas de P. australis (1mm e 5mm) e corers foram estudadas ao longo do gradiente estuarino. As espécies dominantes do sub-conjunto de espécimes medidos não são as mesmas da fauna bentónica original mas, apesar disso, foram capazes de mostrar a sucessão bentónica ao longo do gradiente salino. A distribuição da abundância pelas classes de tamanho estabelecidas para o cálculo do índice ISS não mostrou nenhuma tendência ao longo do gradiente de salinidade em nenhum dos amostradores. Foram encontradas diferenças significativas no comprimento, peso e na relação comprimento-peso dos Anelídeos, Artrópodes, Moluscos e de algumas espécies ao longo do gradiente de salinidade. Não foram encontradas diferenças significativas nos valores AMBI, M-AMBI e ISS ao longo do gradiente estuarino. O EQE das amostras dos corer foi inferior ao dos sacos de folhas. O EQE obtido com o ISS foi mais elevado do que o obtido com o M-AMBI nos sacos de folha, mas não nas amostras do corer. Os efeitos ecológicos associados à contaminação dos sedimentos por efluentes químicos lançados no Canal de Estarreja foram estudados uma década após a sua cessação, recorrendo à Tríade de Qualidade Sedimentar e dois canais de referência. Os resultados mostraram que o sedimento permanece contaminado com elevados níveis de metais e metaloide, disponíveis para serem bioacumulados e com graves consequências ao nível da comunidade. A contaminação do sedimento foi também estudada utilizando a técnica dos sacos de folhas com a macrófita, a alga e um substrato de controlo, tendo-se verificado que as taxas de decomposição, a macrofauna associada e a aplicação dos índices AMBI, M-AMBI e ISS aos sacos de folhas não foram capazes de identificar o problema. Ao contrário do AMBI, o M-AMBI e o ISS apresentaram diferenças significativas entre o canal contaminado e os canais de referência para as amostras do corer. No entanto, a utilização de índices tão complexos é questionável, na medida em que índices mais simples, tais como a S e a H', permitem chegar às mesmas conclusões.
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Sheppy, Margarette Isabell. "An ecological-systems analysis of anorexia nervosa." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/26044.
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Aspects of the ecological systemic approach were used to provide a framework for the understanding of the dynamics of anorexia nervosa and were empirically tested by comparing 30 anorexics and their parents to 34 matched control subjects and their parents. The theoretical model employed was an adaptation of Conger's Ecological-Systems approach which was based on the principles of Bronfenbrennei's theory of human development. The subjects were compared on selected variables arising from the individual, parent, family, and community systems using: 1) the California Psychological Inventory (CPI), 2) the Structural Analysis of Social Behavior (SASB), 3) the Family Environment Scale (FES), and 4) the Pattison Psychosocial Inventory (PPI). Statistical analysis of the difference between means was tested using Hotelling's (T²) procedure followed by a discriminant analysis. The final analysis occured using a Stepwise Discriminant procedure.
The results of the stepwise analysis revealed that the Affiliation score (SASB) for the anorexics and the control subjects and the Psychopathic Deviancy score (CPI-Clinical) of the mothers of the anorexics and the controls were the variables which contributed to the discriminant analysis. With the Affiliation and the Psychopathic Deviancy scores alone, it was possible to correctly classify 87.5% of the research subjects. Analyses also showed statistically significant results at the individual, parent, and family levels. Specifically, the anorexic daughters were found to have a negative self-worth as measured by the SASB. They were also more anxious and at odds with themselves and others (CPI). The anorexics were more depressed than the controls, had a greater tendency toward rebelliousness and hostility toward authority, and expressed their feelings in a more indirect manner. The anorexics may use ritualistic thoughts and actions in an attempt to structure their lives to overcome their feelings of losing control. They lack a sense of who they are emotionally and generally feel alienated and lonely as if on the outside looking in.
The CPI-Psychopathic Deviancy scale was significantly higher for the mothers of the anorexics than for the controls. No differences were found between the two groups of fathers. Interactions within the family, as perceived by the anorexics, were characterized by overprotection and control by the mothers while the anorexics responded with significantly less affiliation to both their mothers and their fathers. The mothers of the anorexics also viewed their daughters as being less friendly in the relationship. There were no significant findings regarding the perceptions of the fathers of the anorexics and the controls. The families of the anorexics were less supportive, helpful and committed to each other than were the families of the control subjects as measured by the FES.Education, Faculty of
Educational and Counselling Psychology, and Special Education (ECPS), Department of
Graduate
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Law, Derek M. "ECOLOGICAL WEED MANAGEMENT FOR ORGANIC FARMING SYSTEMS." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/414.
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Two field studies examining direct ecological weed control practices were conducted in Lexington, Kentucky. The first evaluated weed control efficacy and influence on yields of several mulches in two organically-managed bell pepper (Capsicum annum) production systems for two years. Peppers were planted in double rows in flat, bare ground or on black polyethylene-covered raised beds with drip irrigation, and four mulches (straw, compost, wood chips, and undersown white dutch clover (Trifolium repens L.) living mulch) were applied to the two production systems. In both years, polyethylene-covered raised beds produced higher yields than the flat, bare ground system. In the second year, the polyethylene-covered bed system coupled with mulching in-between beds with compost or wood chips after cultivation provided excellent weed control and yields. The second field study evaluated the efficacy of soil solarization and shallow cultivation on the invasive and noxious weed johnsongrass over two years (Sorghum halapense). A soil solarization treatment, using clear plastic stretched over soil for eight weeks, and a cultivated bare fallow treatment, utilizing a tractor pulled cultivator implement equipped with sweep blades, were randomly applied during the summers of 2003 and 2004 to a field infested with johnsongrass. Solarized and cultivated plots in both years were lightly tilled 8 months after completion of the initial treatment period. At the conclusion of the experiment the johnsongrass population was significantly reduced in all treatments and in the control plots compared to the original infestation. These two experiments testing direct weed control practices (mulching, cultivation, solarization) were undertaken in the context of an ecological weed management plan that includes long term strategies to reduce weed infestations such as crop rotation, cover cropping, and fertility management that are essential for organic farmers.
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White, Andrew. "Temporal and spatial dynamics of ecological systems." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338459.
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Reynolds, Jennifer Joan Heather. "Drivers of population cycles in ecological systems." Thesis, Heriot-Watt University, 2012. http://hdl.handle.net/10399/2530.
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In this thesis, mathematical models are used to investigate potential drivers of population cycles. Population cycles are a common ecological phenomenon, yet the mechanisms underpinning these oscillations are not always known. We focus on two distinct systems, and evaluate potential causes of cyclic dynamics. In the first part of the thesis, we develop and analyse a host–pathogen model, incorporating density-dependent prophylaxis (DDP). DDP describes when individuals invest more in immunity at high population densities, due to the increased risk of becoming infected by a pathogen. The implications of this for the population dynamics of both host and pathogen are examined. We find that the delay in the onset of DDP is critical in determining whether DDP increases or decreases the likelihood of population cycles. Secondly, we focus on a particular cyclic vole population, that of Kielder Forest, Northern UK. We construct a model to test the hypothesis that the population oscillations observed in this location are caused by the interaction between the voles and the silica in the grass they consume. We extend our model by including seasonal forcing, and study the effects of this on the population dynamics.
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Терещенко, Ірина Володимирівна, Ирина Владимировна Терещенко, and Iryna Volodymyrivna Tereshchenko. "Self-management in ecological and economical systems." Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/26798.
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The current system of nature includes two independent systems: material production and environmental protection.
Ecological and economical system (EES) can be defined as the integration of economy and nature, which are interrelated in social production and flow processes in nature and biosphere.
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Peng, Qiuliang. "Periodic differential systems with applications to ecological modelling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0006/NQ29093.pdf.
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Guttal, Vishwesha. "Applications of nonequilibrium statistical physics to ecological systems." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1209696541.
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von, Heland Jacob. "Rowing social-ecological systems: morals, culture and resilience." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-62422.
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The shift from management and governance of ecosystems to relational complex adaptive social-ecological systems (SES) emphasizes a dynamic and integrated humans-in-nature perspective. Such a shift also needs to investigate how diversity and differences in cultures and morals relate to the existence of SES. The papers of this thesis relate these dimensions to SES resilience theory. Paper I analyzes cultural and landscape ecological aspects of trees and tree planting in Androy, Madagascar. Culturally, planting trees serves as a symbol of renewal, purification, agreement and boundary-making. Ecologically, planting trees contributes to the generation of ecosystem services in an otherwise fragmented landscape. Paper II tests the role of forest patches for generating pollination services to local beans that constitute an important protein staple in Androy. The results indicate a significant effect of insect pollination on bean yields and a strong spatial pattern of locating bean plots closer to forests than expected by chance, improving rural food security. Paper III addresses the adaptive capacity of the indigenous forest management in Androy with regard to religious and climatic drivers of change. Paper IV is concerned with cultural analysis of the robustness of provisioning ecosystem services in Androy and the interdependence of morality, cultural practices and generated ecosystem services. Paper V explores how social-ecological memory (SEM) can be seen both as a source of inertia and path dependence and a source of adaptive capacity for renewal and reorganization in the emerging theory about social-ecological systems. Paper VI analyses the film Avatar and discusses ethical–epistemic obligations of researchers as cross-scale knowledge brokers in emerging forms of global environmental politics. The thesis has interdependencies between the social and the ecological and shown that cultural and moral analyses bring important insights and challenges to resilience thinking.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Manuscript. Paper 5: Submitted. Paper 6: In press.
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Kuang, Yan. "Modeling and analysis of competing dynamic ecological systems." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35555.
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Doctor of PhilosophyDepartment of Industrial & Manufacturing Systems Engineering
David H. Ben-Arieh
The dynamic relationship between competing ecological systems has long been and will continue to be one of vital topics in both ecology and mathematical ecology because of its importance and universal existence. Mathematical modeling has become an effective tool to model and simulate the dynamic system, providing decision makers with strategy recommendations. Although a great amount of previous work has attempted to model the biological mechanisms including dispersal, only rarely has there been a systematic investigation on different spatial effects. The author introduces spatial games as a modeling approach with different constructions towards different dynamic systems in order to benefit from the systematic research on spatial dynamics when studying the competing ecological systems. This research developed models of two systems: (1) two-spotted spider mite prey-predator system; (2) tomato spotted wilt virus (TSWV) and west flower thrips (WFT) vector-borne disease system. For two-spotted spider mite system, the author presented four spatial mathematical models as well as a novel spatial game model to describe the spatial movement of two competing species. For the TSWV-WFT system, a spatial game was introduced to describe the spatial dynamics of adult thrips and the novel model was validated with experimental data. The author also gave suggestions for efficiently controlling the vector-borne disease by performing sensitivity analysis towards parameters. The major contribution of this research is to introduce spatial games as a tool to describe the dynamic schemes in ecological systems. Compared to a traditional dynamic model, a spatial game model is more expressive and informative. This approach uses a payoff function and a movement probability function that can be adjusted based on habits, characteristics and mobility schemes of different competing entities, which has enriched its modeling power. The methodology and modeling approach used in this dissertation can be applied to other competing species dynamic systems, and have a broad impact on research areas related to mathematical ecology, biology modeling, epidemiology, pest control, vector-borne disease control, and ecological decision-making processes.
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Haag, Daniel. "Models for the representation of ecological systems? the validity of experimental model systems and of dynamical simulation models as to the interaction with ecological systems /." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962066893.
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Haag, Daniel. "Models for the representation of ecological systems? the validity of experimental model systems and of dynamical simulation models as to the interaction with ecological systems /." [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9386085.
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Abram, Joseph James. "An evaluation of structural loop analysis on dynamic models of ecological and socio-ecological systems." Thesis, University of Southampton, 2018. https://eprints.soton.ac.uk/426888/.
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This thesis evaluates a modelling analysis technique known as Loop Eigenvalue Elasticity Analysis for its utility and application to system dynamic models of ecological and socio-ecological systems. The technique acts as a structural analysis of the interactions within the system and is capable of identifying feedback loops as structural drivers of dynamic behaviour. With adverse behaviours of many ecological systems known to be driven by feedback mechanisms, Structural Loop Analysis could become an important method for increasing our understanding and control over the systems on which we so greatly depend. Within this thesis, a detailed account of the methodology and application of structural loop analysis to ecological dynamic models is undertaken. The focus of the thesis is an assessment of the technique for its ability to improve model design, to increase understanding of system behaviour and ultimately to evaluate if it could be used for the design and implementation of policy surrounding complex ecological and socio-ecological systems. Dynamic system models are predominantly used for exploring the interactions which occur within and between systems. Dynamic system models are used across a wealth of academic fields and, much like the purpose of other models, allow the user to explore and manipulate a system where tests on its real-world equivalent would be impractical or unethical to carry out. Through the exploration of components interactions it is possible to learn about, observe and simulate endogenous drivers of systems as causes of dynamic behaviour and change. While the development and simulation of a dynamic system model can provide a wealth of information over a target system, model output alone can often generate more questions than were initially being asked. Converting a real world system to model format can often lead to black box models, where the combination of multiple system components and interactions between them generate unexpected dynamics, even when interactions at a local level are well understood. The complexity that is inherent to our worldly systems can often translate into the models used to represent them. Within the fields of ecology and socio-ecology, the occurrence of black box models is common and seldom a surprise to the multi-disciplinary approach to system understanding. Ecological and socio-ecological systems are highly complex, naturally incorporating social aspects of human activity and decision making with the natural world, generating an array of human-environment interactions and forming multiple feedback mechanisms between the two spheres. Models of these systems can quickly become just as difficult to interpret as the real world systems, limiting our ability to run and understand sensitivity analysis, conduct meaningful scenario testing or use these models to reflect on policy implementation. Maintaining ecological systems in desirable states is key to developing a growing economy, alleviating poverty and achieving a sustainable future. While the driving forces of an environmental system are often well known, the dynamics impacting these drivers can be hidden within a complex structure of causal chains and feedback loops. It is important that we are always on the lookout for new modelling methods, developing and learning new ways to represent the dynamics and behaviours capable by our target system. Modelling analysis tools are an important step in the modelling process, able to extract additional information of a target system that is often unavailable from model output alone. Exploring analysis tools can bring new techniques and new understanding to our model systems which translates to a greater knowledge and understanding of the target system.
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Dalmazzone, Silvana. "Economic activity and the resilience of ecological systems : complexity, nonlinearities and uncertainty in economic-ecological modelling." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311013.
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Tomlinson, Benjamin John. "Modelling Social-Ecological Systems in the Catalan Coastal Zones." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/384929.
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The Systems Approach Framework (SAF) is a methodological framework designed to enhance the efficacy of human decision-making processes within social-ecological systems with regard to sustainability. The SAF was applied in two case studies in the coastal zone of Catalonia, in two separate European Commission Framework Programme projects entitled “Science and Policy Integration for Coastal System Assessment” (SPICOSA) and “Vectors of Change in Oceans and Seas-marine Life, Impact on Economic Sectors" (VECTORS).
During the SPICOSA application, a common issue of interest to most stakeholders was the water quality (harmful bacteria and water clarity) of the local city beaches, particularly following combined sewer overflow events, and mitigating this impact by using stormwater collectors. Water quality influences the beach users’ decision whether to stay at the beach or to leave, thus affecting the revenue received by the bars and restaurants on the beach front. A social-ecological model was constructed using the methodology outlined in the SAF to represent this issue, so that it could be used as a tool for deliberation between the stakeholders. The model output implies that the stormwater collectors have been useful in improving beach water quality in Barcelona, but there will be diminished returns in constructing more. The value of the beach is clearly large in terms of both non-market value and revenues generated in the nearby bars and restaurants. However, the impact changes in water quality would have on the recreational appeal of the beach is estimated to be low and further research is recommended to determine beach users’ sensitivity to beach closures (bacteria limit exceeded) and turbidity.
At the beginning of the VECTORS project, stakeholders who had participated during the previous SAF application expressed a lack of willingness to engage due to a lack of human resources. The scientific team therefore chose to continue the application with the aspiration of demonstrating the SAF model and results at a later date if the stakeholders found the required resources to engage with the process. There is a general perception that jellyfish abundances are increasing along the Catalan coast. Local authorities are concerned about the stranding events and arrivals of jellyfish to beaches and believe it could reduce the recreational appeal of the beaches. Previous studies also demonstrate the predation of jellyfish (Pelagia noctiluca ephyrae) upon some small pelagic fish larvae (Engraulis encrasicolus). Small pelagics are the principal source of revenue for the local fisheries. A social-ecological model was created in order to capture the effects of changes in abundance of Pelagia noctiluca upon the local fisheries, the tourist industry and the wider economy.
Various future scenarios for different abundances of jellyfish blooms were run. Given the changes that these scenarios would cause on the regional gross domestic product and employment, this study concludes that the overall impact of either of these scenarios on the economy would not be significant at the regional scale.
The inclusion of stakeholders in the SAF methodology is rightly fundamental, but in practice, it can be extremely difficult to persuade key stakeholders to participate, and this is a flaw in the SAF which needs addressing. SAF Application model builders are dependent on stakeholders sharing important data or knowledge but this may be withheld for a variety of reasons including, but not limited to, lack of resources to participate, disinterest, and concern about how the results will be used. The SAF is a well-structured methodology for cases where a mathematical model is both relevant and feasible and should be considered as a useful step-by-step guide for managing coastal zone systems towards sustainability.
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Vander, Meer Elizabeth. "Resisting Incorporation : Considering Biodiversity Beyond Ecological and Economic Systems." Thesis, Lancaster University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518144.
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Guimaraes, Nuno Ana. "Managing social-ecological systems under uncertainty : implications for conservation." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/18974.
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Natural resource managers and conservationists are often confronted with the challenges of uncertainty. Limits to knowledge and predictability challenge conservation success and socio-economic, institutional and political context affect implementation of conservation interventions. Using a management strategy evaluation (MSE) conceptual framework, I use a multidisciplinary approach to gain a better understanding of the role and implications of different sources and types of uncertainty for the management of social-ecological systems, giving special attention to the issues of observation and implementation uncertainty. The conservation of harvested ungulate species in the Serengeti, Tanzania, is used as a case study. I investigated which factors should be prioritized in order to increase survey accuracy and precision, and explored the potential effects of budgetary scenarios on the robustness of the population estimates obtained for different savannah ungulate species. The relative importance of each process affecting precision and accuracy varied according to the survey technique and biological characteristics of the species. I applied specialized questioning techniques developed for studying non-compliant and sensitive behaviour, using the unmatched-count technique (UCT) to assess prevalence of illegal hunting in the Serengeti. I found that poaching remains widespread in the Serengeti and current alternative sources of income may not be sufficiently attractive to compete with the opportunities provided by hunting. I explored trade-offs between different types of error when monitoring changes in population abundance and how these are affected by budgetary, observational and ecological conditions. Higher observation error and conducting surveys less frequently increased the likelihood of not detecting trends and misclassifying the shape of the trend but the differences between multiple levels of observation error decreased for higher monitoring length and frequency. Using key informant interviews with the main actors in the monitoring and management system, I provided recommendations for the development and implementation of interventions within long-term integrated and adaptive frameworks. The research presented in this thesis highlights the need to consider the role of people as influential components within social-ecological systems in order to promote effective conservation interventions. Monitoring and implementation must be understood as dynamic features of the system, instead of merely acting upon it, and the multiple sources of uncertainty must be fully considered in conservation planning, requiring the development and application of tools to aid management decision-making under uncertainty.
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Mancy, Rebecca. "Modelling persistence in spatially-explicit ecological and epidemiological systems." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6219/.
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In this thesis, we consider the problem of long-term persistence in ecological and epidemiological systems. This is important in conservation biology for protecting species at risk of extinction and in epidemiology for reducing disease prevalence and working towards elimination. Understanding how to predict and control persistence is critical for these aims. In Chapter 2, we discuss existing ways of characterising persistence and their relationship with the modelling paradigms employed in ecology and epidemiology. We note that data are often limited to information on the state of particular patches or populations and are modelled using a metapopulation approach. In Chapter 3, we define persistence in relation to a pre-specified time horizon in stochastic single-species and two-species competition models, comparing results between discrete and continuous time simulations. We find that discrete and continuous time simulations can result in different persistence predictions, especially in the case of inter-specific competition. The study also serves to illustrate the shortcomings of defining persistence in relation to a specific time horizon. A more mathematically rigorous interpretation of persistence in stochastic models can be found by considering the quasi-stationary distribution (QSD) and the associated measure of mean time to extinction from quasi-stationarity. In Chapter 4, we investigate the contribution of individual patches to extinction times and metapopulation size, and provide predictors of patch value that can be calculated easily from readily available data. In Chapter 5, we focus directly on the QSD of heterogeneous systems. Through simulation, we investigate possible compressions of the QSD that could be used when standard numerical approaches fail due to high system dimensionality, and provide guidance on appropriate compression choices for different purposes. In Chapter 6, we consider deterministic models and investigate the effect of introducing additional patch states on the persistence threshold. We suggest a possible model that might be appropriate for making predictions that extend to stochastic systems. By considering a family of models as limiting cases of a more general model, we demonstrate a novel approach for deriving quantities of interest for linked models that should help guide modelling decisions. Finally, in Chapter 7, we draw out implications for conservation biology and disease control, as well as for future work on biological persistence.
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Macpherson, Morag Fiona. "Modelling population and disease dynamics in complex ecological systems." Thesis, Heriot-Watt University, 2014. http://hdl.handle.net/10399/2824.
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Mathematical models are a theoretical tool used to understand ecological processes. In this thesis we create mathematical frameworks to describe and evaluate four ecological systems. In the first case study we extend a host-pathogen framework to include a maternal effect which increases the disease resistance of offspring when the maternal environment is poor. Maternal effects impacting life-history traits have been shown to increase the propensity for population cycles. Our contrasting results show maternal effects acting on disease resistance stabilise host-pathogen systems. The second case study examines the impact infection may have on population estimates using Capture-Mark-Recapture (CMR) studies. We show that the estimates using the statistical Program Capture are accurate when capture rates are infection dependent. The final two case studies use spatial, individual-based, stochastic models to simulate disease spread and the colonisation of the Eurasian red squirrel (Sciurus vul- garis) on real-life landscapes. Using novel techniques we highlight the role habitat connectivity has on the dispersal routes which influence the spread of disease and re-population dynamics. Moreover the inclusion of seasonality shows that squirrel population dynamics are driven by the multi-year signal of resources.
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Weerasena, Lakmali. "Optimization models for designing spatially compact ecological reserve systems." Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1253031678/.
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MacKinnon, Richard A. "Examining the work-home interface : an ecological systems perspective." Thesis, University of East London, 2012. http://roar.uel.ac.uk/1599/.
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This dissertation outlines a mixed-methods investigation of work-life balance, examining the construct from an ecological systems theory perspective. This necessitated research at the individual, group, organisational and wider societal levels and included three studies: two using quantitative methodology and one using qualitative. The quantitative phase included two studies that examined the experience of the home-work interface from the perspective of the employee, examining the impact of demographic differences, job design and organisational work-life balance culture on both their work-life balance satisfaction and actual outcomes of work and home domain interaction. This revealed the key role of demographic differences in employees’ satisfaction with work-life balance culture and the moderating role of work locus of control in the relationship between negative domain interaction outcomes and self-reported wellbeing. The qualitative phase involved interviews with senior organisational stakeholders involved in the formulation and deployment of work-life balance policy. Thematic analysis of interview scripts revealed their implicit and explicit limited categorisation of employees when considering work-life balance needs; the gendered nature of their flexible working policies; the key role of line managers in the interpretation and implementation of policy; the impact of communication technology on the interface between work and home domains and the very limited extent of evaluation carried out on flexible-working policies. Taken together, the data paint a complex but illuminating contemporary picture of the nature of work-life balance in the United Kingdom and Republic of Ireland and support the adoption of an ecological systems perspective when examining work-life balance.
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Peres, Edna M. "The translation of ecological resilience theory into urban systems." Thesis, University of Pretoria, 2016. http://hdl.handle.net/2263/56100.
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As an interdependent global society enters an era of unprecedented change, resulting
from unforeseen natural and social disasters and vulnerabilities, the resilience of global
cities to survive is a pressing concern. This dissertation aims to elucidate the application of
resilience thinking by showing how ecological resilience concepts can translate into urban
systems, using the capital of South Africa, Tshwane, as the exploration ground. Resilience
simultaneously embodies the capacity of urban systems to bounce back, adapt or
transform. Translating these concepts into a holistic urban resilience approach answers
three questions: a) What is resilience theory? b) What are the core concepts of ecological
resilience theory? and c) How might these concepts translate to cities?
The dissertation is structured in three parts; to establish the basis of resilience thinking,
explore ecological resilience concepts in an urban system and lastly, assimilate findings into
an urban resilience approach. Qualitative along with historical-comparative research
methods, guided literature studies, and interdisciplinary research designs generated the
finding that ecological resilience concepts translate well into the urban system, but that
urban resilience is not a panacea for the ills of the urban environment.
An urban resilience approach could comprise a) evolutionary or adaptive urban resilience
involving an ongoing study and observation of the city system; and b) transformative urban
resilience, that actively changes systems that reflect stronger or weaker resilience, so as to
purposefully regenerate or collapse? them. This requires responsible and holistic conduct.
Urban resilience thinking implies an appreciation for the complexity that underlies life, and
modesty about ambitions for managing it.Thesis (PhD)--University of Pretoria, 2016.
tm2016
Architecture
PhD
Unrestricted
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Rodrigues, Carla Cristina Morbey. "Topological and dynamical complexity in epidemiological and ecological systems." Doctoral thesis, Universidade de Évora, 2017. http://hdl.handle.net/10174/21241.
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In this work, we address a contribution for the rigorous analysis of the dynamical
complexity arising in epidemiological and ecological models under different types of interactions.
Firstly, we study the dynamics of a tumor growth model, governing tumor cells interacting
with healthy tissue cells and effector cells of the immune system. By using the
theory of symbolic dynamics, we characterize the topological entropy from one-dimensional
iterated maps identified in the dynamics. This analysis is complemented with the computation
of the Lyapunov exponents, the fractal dimension and the predictability of the
chaotic dynamics.
Secondly, we provide the analytical solutions of the mentioned tumor growth model.
We apply a method for solving strongly nonlinear systems - the Homotopy Analysis
Method (HAM) - which allows us to obtain a one-parameter family of explicit series
solutions.
Due to the importance of chaos generating mechanisms, we analyze a mathematical ecological
model mainly focusing on the impact of species rates of evolution in the dynamics.
We analytically proof the boundedness of the trajectories of the attractor. The complexity
of the coupling between the dynamical variables is quantified using observability indices.
The topological entropy of existing one-dimensional iterated maps is characterized using
symbolic dynamics. To extend the previous analysis, we study the predictability and the
likeliness of finding chaos in a given region of the parameter space.
We conclude our research work with the analysis of a HIV-1 cancer epidemiological
model. We construct the explicit series solution of the model. An optimal homotopy
analysis approach is used to improve the computational efficiency of HAM by means of
appropriate values for the convergence control parameter.
We end up this dissertation presenting some final considerations; RESUMO:
Este trabalho constitui um contributo para a análise rigorosa da complexidade dinâmica
de modelos epidemiológicos e ecológicos submetidos a diferentes tipos de interações
Primeiramente, estudamos a dinâmica de um modelo de crescimento tumoral, representando
a interacção de células tumorais com tecidos saudáveis e células efectoras do
sistema imunitário. Usando a teoria da dinâmica simbólica, caracterizamos a entropia
topológica de aplicações unidimensionais identificadas na dinâmica. Esta análise ´e complementada
com o cálculo dos expoentes de Lyapunov, dimensão fractal e o cálculo da
previsibilidade dos atractores caóticos.
Seguidamente, apresentamos soluções analíticas do modelo de crescimento tumoral
mencionado. Aplicamos um método para resolver sistemas fortemente não lineares - o
Método de Análise Homotópica (HAM) - o qual nos permite obter uma família a um
parâmetro de soluções explícitas em forma de série.
Devido à importância dos mecanismos geradores de caos, analisamos um modelo
matemático em ecologia, centrando-nos no impacto das taxas de evolução das espécies na
dinâmica. Provamos analiticamente a compacticidade das trajectórias do atractor. A complexidade
do acoplamento entre as variáveis dinâmicas é quantificada utilizando índices de
observabilidade. A entropia topológica de aplicações unidimensionais é caracterizada usando a dinâmica simbólica. Para estender a análise anterior, estudamos a
previsibilidade e a probabilidade de encontrar comportamento caótico numa determinada
região do espaço de parâmetros.
Concluímos o nosso trabalho de investigação com a análise de um modelo epidemiológico
tumoral HIV-1. Construímos uma solução explícita do modelo. Usamos uma análise homotópica
optimal para melhorar a eficiência computacional do HAM através de valores
apropriados para o parâmetro de controlo da convergência.
Terminamos esta dissertação com a apresentação de algumas considerações finais.
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Hentati-Sundberg, Jonas. "SEA CHANGE : Social-ecological co-evolution in Baltic Sea fisheries." Doctoral thesis, Stockholms universitet, Stockholm Resilience Centre, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-122372.
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Sustainable management of natural resources requires an in-depth understanding of the interplay between social and ecological change. Linked social-ecological systems (SES) have been described as complex adaptive systems (CAS), which mean that they are irreducible, exhibit nonlinear dynamics, have interactions across scales and are uncertain and unpredictable. These propositions have however rarely been tested empirically, in part due to a lack of methodological approaches and suitable datasets. In this thesis, I address this methodological and empirical gap in a study of long-term change of Baltic Sea fisheries. In Paper I, we develop the concept of fishing style through integrating multivariate statistical analysis and in-depth interviews. We thereby identify an intermediate level of detail for analyzing social-ecological dynamics, embracing the case specific and context dependent approaches of the social sciences with the generalizable and quantifiable approaches from the natural sciences. In Paper II we ask: How has the Baltic Sea fishery been regulated over time, and can we identify a way to quantify regulations in order to be able to analyze their effects? We analyze all regulatory changes in Sweden since 1995 with a new methodology and conclude that there is a clear trend towards increased micro-management. In Paper III, we use the fishing styles developed in Paper I and examine how they have changed over time. We relate these changes to the dynamics of regulation (Paper II), as well as to the dynamics of fish stocks and prices. We conclude that regulation has been the main driving force for observed changes, but also that regulation has prompted significant specialization and decline in flexibility for fishers over time. These changes are unintended consequences and may represent a looming risk for the long-term sustainability of this social-ecological system. Paper IV zooms in on a particular fishery, the pelagic trawl fishery for sprat Sprattus sprattus and Atlantic herring Clupea harengus, mainly targeted for the production of fishmeal and fish oil. Suspicions of non-compliance in this fishery motivated us to apply a statistical approach where we used socioeconomic data to re-estimate the historical catches in this fishery (a novel approach to catch-reconstruction estimates). We found that catches had been significantly underreported over several years, with consequences for the quality of stock assessments and management. The study underlines the importance of understanding linked social, economic and ecological dynamics for sustainable outcomes. Finally, Paper V takes a longer historical look at the Baltic Sea fishery, using regionally disaggregated data from 1914-2009 (96 years), which were analyzed with a novel type of nonlinear statistical time-series methods (Empirical Dynamical Modeling). Our analysis explicitly recognized the potential nonlinear dynamics of SES and showed high predictability across regions of catches and prices of cod Gadus morhua and herring. The signal was generally nonlinear and predictability decreased strongly with time, suggesting that the dynamics of this SES are ever-changing. To our knowledge, this is the first long-term analysis of a SES using empirical data and methods developed from the CAS field of research. The main contributions of this thesis are the integrated analysis of social and ecological data, the development of novel methods for understanding SES dynamics, insights on the ever-changing nature of CAS and the quantitative analysis of management outcomes. Future work should focus on assessing the generality of these findings across a broad range of SES and evaluate alternative governance approaches given the complexity and uncertainty of SES suggested by this thesis.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Manuscript.
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Campanaro, Richard. "Socio-ecological coevolution : an ecological analysis of the historical development of international systems in the circumpolar Arctic." Thesis, London School of Economics and Political Science (University of London), 2012. http://etheses.lse.ac.uk/566/.
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The goal of this thesis is to analyse the impact of Arctic ecology on the development of international systems in the circumpolar world. It is a goal pursued in two steps: (i) by developing an analytical approach capable of tracing the mutual constitution of international and ecological systems in world history; and (ii) by using the resulting toolkit to establish a baseline understanding of the international systems of the polar basin. Part One adapts the analytical approach pioneered by Barry Buzan and Richard Little to study international systems in world history, adding a contextual axis to their analytical matrix in order to escape the anthropocentric cul-de-sac that has heretofore limited IR’s ability to consider ecology’s role in the constitution of international units, processes, and structures. The resulting approach – defined in terms of SocioEcological Coevolution – describes this relationship in terms of three sources of explanation: coevolutionary process, ecological capacity and biogeographical structure. Part Two uses the toolkit to analyse the past four hundred years of Arctic history, charting the impact of ecological systems on the principles of membership and behaviour that define international systems in circumpolar world. Through discussions of socio-ecological coevolution, ecological capacity and biogeographical structure, the project identifies the Arctic as a region defined by competing sets of Westphalian and imperial principles. The balance between the Arctic’s anarchic states system and its hierarchic imperial systems has its fulcrum on a socio-ecological ecotone – a transitional gradient that divides its neo-European and non-European biomes and marks a shift from Westphalian to imperial social principles. Though designed to answer specific questions about the constitution of international systems in the circumpolar North, Coevolution proves itself to be a promising tool for ecological analysis in IR with potential applicability to regions outside of the Arctic Basin.
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Barfuss, Wolfram. "Learning dynamics and decision paradigms in social-ecological dilemmas." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20127.
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Kollektives Handeln ist erforderlich um nachhaltige Entwicklungspfade in gekoppelten sozial-ökologischen Systemen zu erschließen, fernab von gefährlichen Kippelementen. Ohne anderen Modellierungsprinzipien ihren Nutzen abzuerkennen, schlägt diese Dissertation die Agent-Umwelt Schnittstelle als die mathematische Grundlage für das Modellieren sozial-ökologischer Systeme vor.
Zuerst erweitert diese Arbeit eine Methode aus der Literatur der statistischen Physik über Lerndynamiken, um einen deterministischen Grenzübergang von etablierten Verstärkungslernalgorithmen aus der Forschung zu künstlicher Intelligenz herzuleiten. Die resultierenden Lerndynamiken zeigen eine große Bandbreite verschiedener dynamischer Regime wie z.B. Fixpunkte, Grenzzyklen oder deterministisches Chaos.
Zweitens werden die hergeleiteten Lerngleichungen auf eine neu eingeführte Umwelt, das Ökologisches Öffentliches Gut, angewendet,. Sie modelliert ein gekoppeltes sozial-ökologisches Dilemma und erweitert damit etablierte soziale Dilemmaspiele um ein ökologisches Kippelement. Bekannte theoretische und empirische Ergebnisse werden reproduziert und neuartige, qualitativ verschiedene Parameterregime aufgezeigt, darunter eines, in dem diese belohnungsoptimierenden Lern-Agenten es vorziehen, gemeinsam unter einem Kollaps der Umwelt zu leiden, als in einer florierenden Umwelt zu kooperieren.
Drittens stellt diese Arbeit das Optimierungsparadigma der Lern-Agenten in Frage. Die drei Entscheidungsparadimen ökonomischen Optimierung, Nachhaltigkeit und Sicherheit werden systematisch miteinander verglichen, während sie auf das Management eines umweltlichen Kippelements angewendet werden. Es wird gezeigt, dass kein Paradigma garantiert, Anforderungen anderer Paradigmen zu erfüllen, sowie dass das Fehlen eines Meisterparadigmas von besonderer Bedeutung für das Klimasystem ist, da dieses sich am Rand zwischen Parameterbereichen befinden kann, wo ökonomische Optimierung weder nachhaltig noch sicher wird.Collective action is required to enter sustainable development pathways in coupled social-ecological systems, safely away from dangerous tipping elements. Without denying the usefulness of other model design principles, this thesis proposes the agent-environment interface as the mathematical foundation for the design of social-ecological system models. First, this work refines techniques from the statistical physics literature on learning dynamics to derive a deterministic limit of established reinforcement learning algorithms from artificial intelligence research. Illustrations of the resulting learning dynamics reveal a wide range of different dynamical regimes, such as fixed points, periodic orbits and deterministic chaos. Second, the derived multi-state learning equations are applied to a newly introduced environment, the Ecological Public Good. It models a coupled social-ecological dilemma, extending established repeated social dilemma games by an ecological tipping element. Known theoretical and empirical results are reproduced and novel qualitatively different parameter regimes are discovered, including one in which these reward-optimizing agents prefer to collectively suffer in environmental collapse rather than cooperating in a prosperous environment. Third, this thesis challenges the reward optimizing paradigm of the learning equations. It presents a novel formal comparison of the three decision paradigms of economic optimization, sustainability and safety for the governance of an environmental tipping element. It is shown that no paradigm guarantees fulfilling requirements imposed by another paradigm. Further, the absence of a master paradigm is shown to be of special relevance for governing the climate system, since the latter may reside at the edge between parameter regimes where economic welfare optimization becomes neither sustainable nor safe.
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Kuckländer, Nina. "Synchronization via correlated noise and automatic control in ecological systems." [S.l.] : [s.n.], 2006. http://opus.kobv.de/ubp/volltexte/2006/1082.
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Gouhier, Tarik Claude. "Causes and consequences of population fluctuations in spatial ecological systems." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:8881/R/?func=dbin-jump-full&object_id=92227.
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Saikaly, Pascal E. "Ecological approach to mitigate toxic shocks in activated sludge systems." Connect to resource online, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1125670988.
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Kuckländer, Nina. "Synchronization via correlated noise and automatic control in ecological systems." Phd thesis, Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2006/1082/.
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The first part is motivated by field studies on feral sheep populations on two islands of the St. Kilda archipelago, which revealed strong correlations due to environmental noise. For a linear system the population correlation equals the noise correlation (Moran effect). But there exists no systematic examination of the properties of nonlinear maps under the influence of correlated noise. Therefore, in the first part of this thesis the noise-induced correlation of logistic maps is systematically examined. For small noise intensities it can be shown analytically that the correlation of quadratic maps in the fixed-point regime is always smaller than or equal to the noise correlation. In the period-2 regime a Markov model explains qualitatively the main dynamical characteristics. Furthermore, two different mechanisms are introduced which lead to a higher correlation of the systems than the environmental correlation. The new effect of "correlation resonance" is described, i. e. the correlation yields a maximum depending on the noise intensity.
In the second part of the thesis an automatic control method is presented which synchronizes different systems in a robust way. This method is inspired by phase-locked loops and is based on a feedback loop with a differential control scheme, which allows to change the phases of the controlled systems. The effectiveness of the approach is demonstrated for controlled phase synchronization of regular oscillators and foodweb models.
Gegenstand der Arbeit ist die Möglichkeit der Synchronisierung von nichtlinearen Systemen durch korreliertes Rauschen und automatische Kontrolle. Die Arbeit gliedert sich in zwei Teile.
Der erste Teil ist motiviert durch Feldstudien an wilden Schafspopulationen auf zwei Inseln des St. Kilda Archipels, die starke Korrelationen aufgrund von Umwelteinflüssen zeigen. In einem linearen System entspricht die Korrelation der beiden Populationen genau der Rauschkorrelation (Moran-Effekt). Es existiert aber noch keine systematische Untersuchung des Verhaltens nichtlinearer Abbildungen unter dem Einfluss korrelierten Rauschens. Deshalb wird im ersten Teils dieser Arbeit systematisch die rauschinduzierte Korrelation zweier logistischer Abbildungen in den verschiedenen dynamischen Bereichen untersucht. Für kleine Rauschintensitäten wird analytisch gezeigt, dass die Korrelation von quadratischen Abbildungen im Fixpunktbereich immer kleiner oder gleich der Rauschkorrelation ist. Im Periode-2 Bereich beschreibt ein Markov-Modell qualitativ die wichtigsten dynamischen Eigenschaften. Weiterhin werden zwei unterschiedliche Mechanismen vorgestellt, die dazu führen, dass die beiden ungekoppelten Systeme stärker als ihre Umwelt korreliert sein können. Dabei wird der neue Effekt der "correlation resonance" aufgezeigt, d. h. es ergibt sich eine Resonanzkurve der Korrelation in Abbhängkeit von der Rauschstärke.
Im zweiten Teil der Arbeit wird eine automatische Kontroll-Methode präsentiert, die es ermöglicht sehr unterschiedliche Systeme auf robuste Weise in Phase zu synchronisieren. Die Methode ist angelehnt an Phase-locked-Loops und basiert auf einer Rückkopplungsschleife durch einen speziellen Regler, der es erlaubt die Phasen der kontrollierten Systeme zu ändern. Die Effektivität dieser Methode zur Kontrolle der Phasensynchronisierung wird an regulären Oszillatoren und an Nahrungskettenmodellen demonstriert.
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Anderies, John M. "Culture, economic structure, and the dynamics of ecological economic systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0004/NQ34506.pdf.
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McGuire, Julia Bayer. "Social ecological food systems| Sustainability lessons from Maine dairy networks." Thesis, The University of Maine, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10300303.
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Milk production has played an integral role in the culture, landscape, and economy of Maine's agriculture. Maine dairy farmers have faced numerous sustainability challenges to economic, environmental, and social aspects of their industry. Like many other complex social ecological systems, the Maine dairy industry faces a gap between scientific knowledge and actionable management or policy. A cultural dichotomy exists between conventional and organic farming. Shifting the focus from this binary, metrics such as social capital may play a key role in solving sustainability issues. Difficulties arise in the governance of complex social ecological systems when the scales of assessment, management, and policy do not match principal challenges. Despite efforts by many, Maine dairy challenges may be fueled by a state political system that is restricted by term limits and short legislative sessions. Piecemeal policy-making leads to assessment and policy outcomes that do not take the complexities of the system into consideration.
In the case of the Maine dairy industry, using mental modeling and social network analysis: 1) we seek to explore a method that may improve understanding in cases of disintegration between sustainability policy and action; 2) we test whether social capital, measured using Maine dairy farmers' information networks, spans perceived boundaries between conventional and organic management and between different farm sizes, and; 3) we investigate the scale problemscape for long-term success of the Maine dairy industry.
We found no significant difference in the importance of the economic, environmental, or social factors that dairy farmers considered to be the most challenging to industry sustainability. Social capital, rather than farm management practice or size, is a critical variable for better understanding industry sustainability. We found gaps between the current industry policy structure and the management and assessment scales required to address sustainability challenges. The barriers to effective long-term management, assessment, and policy are numerous for the Maine dairy industry. Our findings suggest that solutions concentrating on only one sustainability factor are unlikely to work in the longterm. Solutions may lie in a more holistic evaluation process, and inclusion of social capital and scale assessments to effectively link science and policy.
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AlAdwani, Mohammad S. Kh F. Sh. "Understanding the effects of functional responses in ecological dynamical systems." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/121887.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2019Cataloged from PDF version of thesis.
Includes bibliographical references (pages 45-46).
The main purpose of incorporating functional responses into ecological models has been to add more realism and to help us to mechanistically explain the dynamics of species abundances in nature. Yet, their effects have not been widely understood, especially in multispecies systems. That is, it remains unclear whether the perceived benefits of adding functional responses are simply mathematical artefacts or not. For example, while functional responses have been useful to model the dynamics of 2-species systems, still some functional responses have been criticized for producing unrealistic results. Moreover, it has been unclear the extent to which adding functional responses in multispecies systems can allow the dynamics to reach any type of behavior, contrary to the limits that nature may impose. Thus, it is necessary to fully understand the effect of functional responses on ecological models as it is directly linked to their explanatory power of ecological dynamics.
In this Masters thesis, we examine the effect of functional responses in 2-species and multi-species models (or systems). In particular, we examine the number of interior fixed points that are added into dynamical models by introducing functional responses. This number is linked to the capacity of a model to fit data and to the model's sensitivity to perturbation in its parameters. Note that classic ecological models without functional responses have only one interior fixed point regardless of the dimension of the system. We introduce, for the first time, a methodology to count the number of interior fixed points present in a dynamical system with functional responses. In particular, for 2-species models, we uncouple the 2-variable isocline equations (after some manipulations) into two separate single variable equations and examine them. For multispecies models, we compute the mixed volume (number of interior fixed points) of the system's isocline equations (after some manipulation).
We show that incorporating functional responses into 2-species models feeds the system with one or two extra interior fixed points. Importantly, this number increases exponentially in multispecies systems. Hence, we conclude that the explanatory power of multispecies models with functional responses is drastically reduced if model parameters are not ecologically restricted. We believe this work sheds new lights on the applicability of functional responses and opens a new dialogue of what constitutes a realistic model.
by Mohammad S KH F SH AlAdwani.
S.M.
S.M. Massachusetts Institute of Technology, Department of Civil and Environmental Engineering
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Hau, Jorge Luis. "Toward environmentally conscious process systems engineering via joint thermodynamic accounting of industrial and ecological systems." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1117650243.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xxii, 306 p.; also includes graphics. Includes bibliographical references (p. 290-306). Available online via OhioLINK's ETD Center
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Hau, Jorge L. "Toward environmentally conscious process systems engineering via joint thermodynamic accounting of industrial and ecological systems." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1117650243.
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Ó, Duibhir Conall. "Simulating Systems : Interactive computer simulations as an educational tool for teaching about social-ecological systems." Thesis, Linnéuniversitetet, Institutionen för kulturvetenskaper (KV), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105265.
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This study adopts an experimental design to examine the use, in practice, of interactive computer simulations as educational tools. With the accelerated use of digital learning and the urgency of implementing sustainable development, the important role of interactive computer simulations is examined. While rooted in the digital humanities, the study focuses on ecopedagogy as a theoretical lens by which to assess critical learning. Drawing on previous research, ‘Shiny’ was used to develop a simple, interactive application consisting of a tool where users can calculate the cost and carbon emissions of energy production within a specific system. This application was used as part of a participatory experiment with 47 participants, and the data returned was analysed to examine its educational merit. The findings of the study indicate positive engagement with the simulation tool used, along with important lessons for further study.
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Saikaly, Pascal. "Ecological approach to mitigate toxic shock loads in acivated sludge systems." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1125670988.
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de, la Torre-Castro Maricela. "Humans and Seagrasses in East Africa : A social-ecological systems approach." Doctoral thesis, Stockholm University, Department of Systems Ecology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1061.
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The present study is one of the first attempts to analyze the societal importance of seagrasses (marine flowering plants) from a Natural Resource Management perspective, using a social-ecological systems (SES) approach. The interdisciplinary study takes place in East Africa (Western Indian Ocean, WIO) and includes in-depth studies in Chwaka Bay, Zanzibar, Tanzania. Natural and social sciences methods were used. The results are presented in six articles, showing that seagrass ecosystems are rich in seagrass species (13) and form an important part of the SES within the tropical seascape of the WIO. Seagrasses provide livelihoods opportunities and basic animal protein, in from of seagrass associated fish e.g. Siganidae and Scaridae. Research, management and education initiatives are, however, nearly non-existent. In Chwaka Bay, the goods and ecosystem services associated with the meadows and also appreciated by locals were fishing and collection grounds as well as substrate for seaweed cultivation. Seagrasses are used as medicines and fertilizers and associated with different beliefs and values. Dema (basket trap) fishery showed clear links to seagrass beds and provided the highest gross income per capita of all economic activities. All showing that the meadows provide social-ecological resilience. Drag-net fishery seems to damage the meadows. Two ecological studies show that artisanal seaweed farming of red algae, mainly done by women and pictured as sustainable in the WIO, has a thinning effect on seagrass beds, reduces associated macrofauna, affects sediments, changes fish catch composition and reduces diversity. Furthermore, it has a negative effect on i.a. women’s health. The two last papers are institutional analyses of the human-seagrass relationship. A broad approach was used to analyze regulative, normative and cultural-cognitive institutions. Cooperation and conflict take place between different institutions, interacting with their slow or fast moving characteristics, and are thus fundamental in directing the system into sustainable/unsustainable paths. Ecological knowledge was heterogeneous and situated. Due to the abundance of resources and high internal control, the SES seems to be entangled in a rigidity trap with the risk of falling into a poverty trap. Regulations were found insufficient to understand SES dynamics. “Well” designed organizational structures for management were found insufficient for “good” institutional performance. The dynamics between individuals embedded in different social and cultural structures showed to be crucial. Bwana Dikos, monitoring officials, placed in villages or landing sites in Zanzibar experienced four dilemmas – kinship, loyalty, poverty and control – which decrease efficiency and affect resilience. Mismatches between institutions themselves, and between institutions and cognitive capacities were identified. Some important practical implications are the need to include seagrass meadows in management and educational plans, addressing a seascape perspective, livelihood diversification, subsistence value, impacts, social-ecological resilience, and a broad institutional approach.
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Schultz, Lisen. "Nurturing resilience in social-ecological systems : Lessons learned from bridging organizations." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-27503.
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In an increasingly complex, rapidly changing world, the capacity to cope with, adapt to, and shape change is vital. This thesis investigates how natural resource management can be organized and practiced to nurture this capacity, referred to as resilience, in social-ecological systems. Based on case studies and large-N data sets from UNESCO Biosphere Reserves (BRs) and the UN Millennium Ecosystem Assessment (MA), it analyzes actors and social processes involved in adaptive co-management on the ground. Papers I & II use Kristianstads Vattenrike BR to analyze the roles of local stewards and bridging organizations. Here, local stewards, e.g. farmers and bird watchers, provide on-site management, detailed, long-term monitoring, and local ecological knowledge, build public support for ecosystem management, and hold unique links to specialized networks. A bridging organization strengthens their initiatives. Building and drawing on multi-level networks, it gathers different types of ecological knowledge, builds moral, political, legal and financial support from institutions and organizations, and identifies windows of opportunity for projects. Paper III synthesizes the MA community-based assessments and points to the importance of bridging organizations, leadership and vision, knowledge networks, institutions nested across scales, enabling policies, and high motivation among actors for adaptive co-management. Paper IV explores learning processes catalyzed by bridging organizations in BRs. 79 of the 148 BRs analyzed bridge local and scientific knowledge in efforts to conserve biodiversity and foster sustainable development, provide learning platforms, support knowledge generation (research, monitoring and experimentation), and frame information and education to target groups. Paper V tests the effects of participation and adaptive co-management in BRs. Local participation is positively linked to local support, successful integration of conservation and development, and effectiveness in achieving developmental goals. Participation of scientists is linked to effectiveness in achieving ‘conventional’ conservation goals and policy-makers enhance the integration of conservation and development. Adaptive co-management, found in 46 BRs, is positively linked to self-evaluated effectiveness in achieving developmental goals, but not at the expense of conservation. The thesis concludes that adaptive collaboration and learning processes can nurture resilience in social-ecological systems. Such processes often need to be catalyzed, supported and protected to survive. Therefore, bridging organizations are crucial in adaptive co-management.
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Marttila, M. (Maare). "Ecological and social dimensions of restoration success in boreal river systems." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526217253.
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Abstract The degradation of rivers and streams has led to world-wide efforts to restore freshwater habitats. A good understanding of the social-ecological context is considered key to successful restoration. In this thesis, a multidisciplinary framework was applied to study ecological and social dimensions of restoration success. First, the long-term performance of in-stream restoration measures was examined by conducting repeated cross-sectional surveys in restored streams up to 20 years post-restoration. Next, nationwide electrofishing data were used to assess the density responses of juvenile salmonids to habitat restoration and factors influencing restoration success were examined. Finally, changes in the provision of ecosystem services were evaluated by comparing the perceptions of restoration outcomes between two user groups and three study rivers. The results indicated that the restoration-induced increase in habitat heterogeneity persisted over time, initiating an overall positive development also in biological metrics (i.e. juvenile salmonids and aquatic mosses). However, overall substrate variability in restored streams remained lower than in near-pristine streams, with a shortage of gravel beds. Fish responses varied strongly between rivers, which was explained mainly by watershed scale (e.g. river basin size, dominant geology) and local (potential interspecific competition) factors. Site-specific differences were also observed in the delivery of ecosystem services, mainly reflecting stakeholder perceptions of landscape value and fish provisioning. Overall, the results show that setting indicators and target levels for restoration success is grounded on perspective. Socially conscious ecological restoration that acknowledges local specialities and needs in priority setting, planning and implementation has the potential to provide multiple benefits for river ecosystems and societyTiivistelmä Virtavesien ekologisen tilan heikentyminen on johtanut maailmanlaajuisiin toimiin niiden elinympäristöjen kunnostamiseksi. Usein ekologisen kunnostuksen onnistuminen edellyttää kuitenkin ihmisen ja ympäristön vuorovaikutussuhteiden laaja-alaista ymmärtämistä. Tässä väitöskirjatutkimuksessa käytettiin monitieteistä viitekehystä virtavesikunnostusten ekologisten ja sosiaalisten vaikutusten tutkimiseen. Ensimmäisessä osatyössä arvioitiin kunnostustoimenpiteiden kestävyyttä sekä uoman rakenteellisen monimuotoisuuden kehittymistä pitkällä aikavälillä (10-20 vuotta kunnostusten jälkeen). Toisessa osatyössä tehtiin valtakunnallisen sähkökalastusaineiston avulla meta-analyysipohjainen yhteenveto suomalaisten virtavesikunnostusten vaikutuksista taimenen ja lohen kesänvanhojen (0+) poikasten tiheyteen sekä tutkittiin kunnostustulokseen vaikuttavia ympäristötekijöitä. Kolmannessa osatyössä selvitettiin kunnostusten onnistumista ekosysteemipalvelujen näkökulmasta vertaamalla kahden eri käyttäjäryhmän kokemia muutoksia kolmen tutkimusjoen välillä. Väitöskirjan tulokset osoittivat, että kunnostukset lisäsivät jokiuoman rakenteellista monimuotoisuutta sekä lyhyellä että pitkällä aikavälillä ja vaikuttivat myönteisesti myös biologisiin indikaattoreihin (lohikalojen poikastiheys ja vesisammalet). Vaihtelu pohjan laadussa oli kuitenkin luonnontilaisia uomia vähäisempää ja erityisesti kutuun soveltuvaa soraa oli niukasti. Lohikalojen tiheysvaste vaihteli voimakkaasti jokien välillä, mikä selittyi pääasiassa valuma-alueeseen liittyvillä (esim. valuma-alueen koko ja geologia) ja paikallisilla (mahdollinen lajien välinen kilpailu) tekijöillä. Paikkasidonnaisia eroja havaittiin myös vaikutuksissa ekosysteemipalveluihin ja ne heijastivat etenkin maisemassa ja kalasaaliissa koettuja muutoksia. Tutkimus osoitti, että erilaiset taustat ja odotukset vaikuttavat vahvasti siihen, millaisten kriteerien perusteella kunnostusten onnistumista arvioidaan. Jotta kunnostuksilla saavutettaisiin hyötyjä sekä jokiekosysteemeille että yhteiskunnalle, on tärkeää tuntea paikalliset erityispiirteet ja -tarpeet ja ottaa ne huomioon kunnostuskohteiden valinnassa sekä toimenpiteiden suunnittelussa ja toteutuksessa
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Reinke, Diane Carolyn. "A human ecological systems perspective on family violence in Canada's North." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ21203.pdf.
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Torre-Castro, Maricela de la. "Humans and seagrasses in East Africa : a social-ecological systems approach /." Stockholm : Department of Systems Ecology, Stockholm University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-1061.
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Culbertson, Trisha L. "Ecological implications for sustainable stormwater systems in the tallgrass prairie region." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/793.
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McLean, K. M. "Ecological studies on sulphate-reducing bacteria in offshore oil storage systems." Thesis, University of Aberdeen, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377605.
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The object of this thesis was to examine microbial interactions in offshore crude oil storage systems with special reference to the role played by the sulphate-reducing bacteria (SRB). The aim was to characterise the SRB present in such systems; to isolate and characterise crude oil-degrading bacteria and to develop simple models of the system. SRB were shown to be present in samples from offshore by the detection of high levels of SRB and sulphide, and of depleted sulphate levels. SRB were enriched for, isolated and characterised from offshore oil storage facilities and pure cultures of the organisms Desulfovibrio desulphuricans, Desulfovibrio sapovorans, Desulfobacter postgatei and Desulfobulbus propionicus were isolated. Desulfobacter was shown to be the key organism in this environment, responsible for the terminal oxidation of acetate produced from the incomplete oxidation of higher fatty acids by the Desulfovibrio spp. and the Desulfobulbus. The enrichment, isolation and partial characterisation of oil-degrading bacteria of the genera Pseudomonas and Micrococcus was also carried out. These organisms were shown to use both aliphatic and aromatic components of crude oil. The breakdown of hydrocarbons provides both the anaerobic conditions and carbon sources necessary for the growth of SRB. Liquid and gel-stabilised model systems in which both the temporal and spatial development of oil-degrading communities (including SRB) were constructed.
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Hale, James David. "Elucidating the drivers, contextual sensitivity and resilience of urban ecological systems." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/6238/.
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As the global population urbanises, the benefits derived from contact with nature increasingly depend upon the presence of diverse urban ecological communities. These may be threatened by changes in land-cover and the intensification of land-use. A key question is how to design and manage cities to retain desirable species, habitats and processes. Addressing this question is challenging, due to the dominant role of humans in shaping spatially and temporally complex urban landscapes. Earlier research identified ecological patterns along urban–rural gradients, often using simplified measures of built form and disturbance. The central theme within this thesis is that we require a more mechanistic understanding of the processes that created today‘s ecological patterns, which recognises the interactions between social and ecological sub-systems. Using bats (Chiroptera) as a case study group, I identified a broadly negative association between bat activity and built density. Urban tree networks appeared beneficial for one species, and further work revealed that their role in facilitating movement depended upon the size of gaps in tree lines and their illumination level. Resilience analyses were used to map diverse dependencies between the functioning of urban bat habitats and human social factors; illustrating the value of a more mechanistic systems-based approach.