Dissertations / Theses: 'Energy Ecosystems'

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Sharifi, Leila. "Energy-aware service provisioning in P2P-assisted cloud ecosystems." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/404387.

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Energy has been emerged as a first-class computing resource in modern systems. The trend has primarily led to the strong focus on reducing the energy consumption of data centers, coupled with the growing awareness of the adverse impact on the environment due to data centers. This has led to a strong focus on energy management for server class systems. In this work, we intend to address the energy-aware service provisioning in P2P-assisted cloud ecosystems, leveraging economics-inspired mechanisms. Toward this goal, we addressed a number of challenges. To frame an energy aware service provisioning mechanism in the P2P-assisted cloud, first, we need to compare the energy consumption of each individual service in P2P-cloud and data centers. However, in the procedure of decreasing the energy consumption of cloud services, we may be trapped with the performance violation. Therefore, we need to formulate a performance aware energy analysis metric, conceptualized across the service provisioning stack. We leverage this metric to derive energy analysis framework. Then, we sketch a framework to analyze the energy effectiveness in P2P-cloud and data center platforms to choose the right service platform, according to the performance and energy characteristics. This framework maps energy from the hardware oblivious, top level to the particular hardware setting in the bottom layer of the stack. Afterwards, we introduce an economics-inspired mechanism to increase the energy effectiveness in the P2P-assisted cloud platform as well as moving toward a greener ICT for ICT for a greener ecosystem.
La energía se ha convertido en un recurso de computación de primera clase en los sistemas modernos. La tendencia ha dado lugar principalmente a un fuerte enfoque hacia la reducción del consumo de energía de los centros de datos, así como una creciente conciencia sobre los efectos ambientales negativos, producidos por los centros de datos. Esto ha llevado a un fuerte enfoque en la gestión de energía de los sistemas de tipo servidor. En este trabajo, se pretende hacer frente a la provisión de servicios de bajo consumo energético en los ecosistemas de la nube asistida por P2P, haciendo uso de mecanismos basados en economía. Con este objetivo, hemos abordado una serie de desafíos. Para instrumentar un mecanismo de servicio de aprovisionamiento de energía consciente en la nube asistida por P2P, en primer lugar, tenemos que comparar el consumo energético de cada servicio en la nube P2P y en los centros de datos. Sin embargo, en el procedimiento de disminuir el consumo de energía de los servicios en la nube, podemos quedar atrapados en el incumplimiento del rendimiento. Por lo tanto, tenemos que formular una métrica, sobre el rendimiento energético, a través de la pila de servicio de aprovisionamiento. Nos aprovechamos de esta métrica para derivar un marco de análisis de energía. Luego, se esboza un marco para analizar la eficacia energética en la nube asistida por P2P y en la plataforma de centros de datos para elegir la plataforma de servicios adecuada, de acuerdo con las características de rendimiento y energía. Este marco mapea la energía desde el alto nivel independiente del hardware a la configuración de hardware particular en la capa inferior de la pila. Posteriormente, se introduce un mecanismo basado en economía para aumentar la eficacia energética en la plataforma en la nube asistida por P2P, así como avanzar hacia unas TIC más verdes, para las TIC en un ecosistema más verde.

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Arkwright, Ashlie Beals. "Fourth and Eighth Grade Students' Conceptions of Energy Flow through Ecosystems." UKnowledge, 2014. http://uknowledge.uky.edu/edsc_etds/3.

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This mixed methods status study examined 32 fourth grade students’ conceptual understandings of energy flow through ecosystems prior to instruction and 40 eighth grade students’ conceptual understandings of the same topic after five years of daily standards-based instruction in science. Specific ecological concepts assessed related to: 1) roles of organisms; 2) the sun as the original energy source for most ecosystems; and 3) interdependency of organisms. Fourth and eighth grade students were assessed using the same three-tiered forced-choice instrument, with accompanying tasks for students to defend their forced-choice selections and rate their level of confidence in making the selections. The instrument was developed for the study by a team of researchers and was based on similar tasks presented in the research literature. Distractor options were embedded in each assessment task using common non-scientific ideas also reported in the research literature. Cronbach’s alpha values at or greater than .992 for each task indicated inter-rater consistency of task answers, and Rasch analysis was employed to establish the reliability of the instrument. Qualitative and quantitative analyses were employed to assess the data. Constant comparative methods were employed to analyze students’ written responses, which were coded and grouped into emerging themes. These themes were further developed to characterize students’ conceptual understandings. Student open responses also were scored and coded by a team of researchers using a rubric to identify level of scientific understanding. Quantitative analyses included Rasch analysis used to normalize survey data. Independent samples t-tests were then employed to compare students’ forced-choice responses to their written responses and to the confidence ratings, as well as to compare fourth and eighth grade students’ responses. Findings indicated that eighth grade students generally outperformed the fourth grade on both the forced-choice and written responses, but both groups demonstrated conceptual difficulties in all three topics assessed. Thus, results from the current study support the assertion that students’ understanding of concepts related to energy flow in ecosystems is not at the expected level according to national science education standards and frameworks. Conceptual difficulties identified in the study are discussed along with implications and curricular recommendations.

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Schneider, Katie. "How the availability of nutrients and energy influence the biodiversity of cave ecosystems." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9182.

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Thesis (Ph.D.) -- University of Maryland, College Park, 2009.
Thesis research directed by: Behavior, Ecology, Evolution and Systematics Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Davis, Philip Browning. "The invasion potential and competitive ability of Camelina sativa (L.) Crantz (camelina) in rangeland ecosystems." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/davis/DavisP0510.pdf.

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Camelina sativa (L.) Crantz (large-seeded false-flax) is a recently introduced oilseed crop in Montana and has potential for large scale production for the biofuel market. However, due to weedy characteristics, the invasive potential of this species is of concern. A need exists to create a pre-entry protocol to accurately assess risk to minimize uncertainty inherent in qualitative weed risk assessment approaches. We assessed the probability of C. sativa to invade rangeland ecosystems of southwest Montana to address this concern. The objectives of this study were to 1) quantitatively assess the invasion potential of C. sativa by collecting demographic data over two years and developing a population dynamics model, 2) compare experimental results and modeling outcomes to predictions suggested by a qualitative weed risk assessment system, and 3) assess the impact of growing conditions on the relative competitiveness of C. sativa and Brassica napus (L.) (canola). Objective 1 was carried out in two contrasting rangeland ecosystems to assess the effects of disturbance and seeding season on emergence, survival, and fecundity rates of C. sativa. Population growth (lambda) was forecasted by developing a population dynamics model. Resulting lambda values from simulations using observed data never exceeded 0.03 and the maximum time to extinction was six years. The low lambda values indicate that the threat of invasion by this species in the studied ecosystems is low. Objective 2 compared quantitative results to predictions from the Australian weed risk assessment (WRA) model. In contrast to experimental results, outcomes from the WRA suggested that this species should not be allowed entry into the region. These opposing results highlight the need for a more comprehensive approach to weed risk assessment. Objective 3 was conducted over three trials in two greenhouses. A replacement series design was used to estimate the effects of soil conditions and the presence of an invasive weed, Bromus tectorum (L.) (cheatgrass, downy brome), on the competitive outcomes between C. sativa and canola. Replacement series diagrams determined that competition occurred and that canola was the superior competitor in all treatments, thus providing further evidence that the invasion potential of C. sativa is low.

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Urban, Robert Anthony. "Toward Sustainability through Techno-Ecological Synergy: Including Ecosystems in Engineering Design and Analysis." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354589871.

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Savage, Leah Krystyn. "Urban ecosystems and human health in South Africa : examining the relationships between housing, energy, indoor air quality and respiratory health." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/819.

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Alsultan, Mohammed. "Can rural Gaza Strip be both biogas “self-sufficient” and organic waste and wastewater problem free?" Thesis, Högskolan Kristianstad, Avdelningen för miljö- och biovetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-21722.

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The rural areas in the Gaza Strip suffer from the problem of sanitation and organic waste as well as electricity and cooking fuel. In this thesis, the biogas plant was designed to solve those problems based on the fixed dome plant design as shown in Figure 3 and4. Therefore, the efficiency and selectivity was good for biogas plant which is easy for the local people disposal of organic waste and wastewater as well as self-sufficiency of biogas for cooking and electricity for the family. The sediments from the biogas plant are also used as fertilizers in agriculture. Thus it is possible to know the amount of biogas production, the cost of biogas, the amount of fertilizer, the cost of fertilizers and the amount of disposal of organic waste and wastewater. The calculation shows that the size of digester which is equal to 12 cubic meters as shown in figure 4.The construction is cost of $ 930 as shown in Table 2. Through the results will be disposed of organic waste, wastewater and manure are about 48 kilograms per day for the family. The Biogas is produced 0.5 tons of biogas is estimated about $ 100 in rural areas in the Gaza Strip. It is also produced fertilizers equivalent of $ 113 per month. So the results and calculations are clear that the rural family is self-sufficient of biogas, the dispose of organic waste and wastewater and agricultural growth by the fertilizers from the biogas plant.

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Haglund, Leo, and Emil Jonsson. "Industrial Internet of Things Collaborations : A Contingency Framework for Smart Grid Development in Renewable Energy." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-85212.

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Purpose - As energy demand increases in tandem with an increasing climate crisis, the world runs towards renewable energy generation. Within the area of Industrial Internet of Things (IIoT) there are a multitude of opportunities that should be capitalized on, but this requires an integration of the connected systems of Information Technology (IT) and the governing systems of Operational Technology (OT). In the utility sector, this has proven very complex. Hence, the purpose of this paper is to explore the challenges between utility companies, IT providers, and OT providers in the ecosystem to identify activities to combat these challenges by developing a contingency framework. Thus, contributing to the development of Smart Grids (SG) within renewable energy generation. Method – To fulfill the purpose of this study, the partnership between the Swedish branch of a global technology company and a sizeable Swedish energy producer has been investigated. A qualitative single case study has been conducted with an inductive, explorative approach. Empirical data were collected from 22 interviews and 4 workshops from six different companies across five countries. The interviews and workshops were conducted in three different waves: 1) Explorative, 2) Investigatory, and 3) Validatory. The data were analyzed using thematic analysis. Findings – Findings from our data analysis have identified challenges and key activities in four main categories: 1) IT/OT Collaborative Challenges, 2) IT/OT Technical Challenges, 3) IT/OT Collaborative Activities, and 4) IT/OT Technical Activities. These findings are combined to form a contingency framework that emphasizes the activities to overcome industry challenges. Theoretical and Practical Implications – Our findings and framework expand on current literature in IIoT, SGs, and Innovation Ecosystems development by investigating the collaborative challenges and activities within IT/OT collaboration rather than specific technologies or ecosystem structures. It also expands the literature on IT/OT convergence by taking a broader ecosystem perspective than only IT and OT companies. Our framework provides practical contributions for managers by identifying key challenges and activities and how these relate to each other. Limitations and Future Research – Our study is limited to a single case study on wind power generation in northern Europe. Therefore, future studies are recommended to investigate if our findings apply to other companies, industry sectors, and geographical areas.

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Thieme, Christoph-Josef [Verfasser], Eckart [Akademischer Betreuer] Priesack, Eckart [Gutachter] Priesack, and Urs [Gutachter] Schmidhalter. "Measurements and modelling of energy and greenhouse gas fluxes from complex cropland ecosystems / Christoph-Josef Thieme ; Gutachter: Eckart Priesack, Urs Schmidhalter ; Betreuer: Eckart Priesack." München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/1185069674/34.

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Steyn, Clara. "Changes in food web structure and energy flow in kelp forest ecosystems on the south-west coast of South Africa following the invasion of Jasus lalandii." Master's thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/30837.

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In the early 1990s the west coast rock lobster Jasus lalandii underwent an eastward shift in distribution into an area known as East of Cape Hangklip where they had previously been rare. This shift has also been termed an invasion and resulted in a complete change in the benthic community structure, changing from one state dominated by herbivores and encrusting algae, to another state dominated by lobsters, sessile species, kelp and understory foliose algae. Using the trophic modelling software Ecopath with Ecosim, baseline models of the pre- and Post-invasion systems were created to better understand trophic pathways between the two different states and assess how fishing pressure may have driven the shift in ecosystem state. Using the baseline models, different fishing management strategies were tested to see whether the post lobster-invaded ecosystem could be shifted back or close to the pre-invasion state. Baseline models that were developed to describe the shift in ecosystem state reflected an increase in the presence of kelp, sessile species and lobsters, and the decline of encrusting algae and herbivores. Furthermore, the baseline models reflect the Postinvasion system as more productive and less diverse than the pre-invasion system. Simulations using an Ecosim model showed that, with a reduction in fishing pressure on reef fish and abalone and a simulated increase in fishing pressure on rock lobster, reef fish and adult abalone recovered to pre-invasion levels, whereas juvenile abalone and urchin biomass did not recover, likely due to the difficulty in capturing non-trophic interactions in the trophic models. Further functional groups such as sessile species, turf and foliose algae, also did not return to the pre-invasion state. This study concluded that a reduction in fishing pressure on abalone and reef fish, and the removal of rock lobster through increased fishing pressure, would allow the post-invasion ecosystem to partially recover to the pre-invasion state, but not completely, suggesting a hysteresis effect. Further exploration of management strategies through model simulations is needed, including those that can account for non-trophic links.

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Strandmark, Alma. "Baltic shore-lands facing climate change." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-141794.

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This thesis provides new insight concerning drivers behind differences in arthropod diversity and abundance in Baltic shore ecosystems and how the arthropod communities might be affected when the conditions in the Baltic Sea are altered due to climate change. The focus has been on climate related changes that are unique for coastal ecosystems, especially sea level rise and changes in the inflow of marine nutrients. As sea levels rise, features in coastal landscapes will be altered, islands and habitats will be flooded and diminished, and structural connectivity within the island landscape will therefore change. This thesis shows that arthropod diversity within the two arthropod groups, spiders and beetles, increases with island size but also that diversity is positively influenced by a high number of islands in the surroundings. A changed distribution and occurrence of marine species, due to climate change or eutrophication, can also affect terrestrial organisms on the shore. In the Baltic Sea the new conditions following climate change will decrease the prevalence of bladder-wrack and benefit filamentous algae. Algal deposits on shores reflect the marine species composition and a decreased prevalence of bladder-wrack in the Baltic Sea will also be visible on the shores. This thesis shows that a lower proportion of bladder-wrack in the algal deposits will decrease the diversity and abundance of arthropods in these deposits. Changes in the marine environment may also affect the inflow of insects with aquatic life stages and terrestrial adult stages. On Baltic shores, prey species with aquatic life stages, especially chironomids, constitute a large proportion of the diet of the terrestrial predatory group, wolf spiders. In freshwater system, the inflow of chironomids is known to decrease with elevated water temperatures if this is true in the Baltic Sea prey availability of wolf spiders would decrease. This thesis supports the importance of chironomids as a prey for coastal wolf spiders, but also shows that the diet varies over season with dominance of terrestrial prey in early summer shifting to a dominance of marine prey in late summer and autumn. This seasonal variation is primarily due to a gradual increase in the consumption of chironomids over season. Climate change has the potential to alter the biogeographical conditions in coastal landscapes as well as the density and quality of marine nutrient inflow. Sea level rise will diminish and flood islands and this thesis shows that a moderate sea level rise of 0.5 meters would make the total number of islands in the outer part of Stockholm archipelago decrease with about 25 %. Sea level rise could thus have consequences for arthropod diversity in Baltic shore meadows in the near future. The combined effects of sea level rise and changed prevalence of marine species in the Baltic Sea will affect the abundance and diversity of arthropods substantially. The abundance and diversity of spiders and beetles will decrease on shores that today have a high occurrence of bladder-wrack and prey availability for coastal predators might decrease due to a decreased inflow of chironomids. Changes in the arthropod communities could have consequences also further up in the food chain, such as for shore birds feeding on these arthropods.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.

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Engel, Max [Verfasser], Helmut [Akademischer Betreuer] Brückner, Frank [Akademischer Betreuer] Schäbitz, and Christophe [Akademischer Betreuer] Morhange. "The chronology of prehistoric high-energy wave events (tropical cyclones, tsunamis) in the southern Caribbean and their impact on coastal geo-ecosystems : a case study from Bonaire (Leeward Antilles) / Max Engel. Gutachter: Helmut Brückner ; Frank Schäbitz ; Christophe Morhange." Köln : Universitäts- und Stadtbibliothek Köln, 2012. http://d-nb.info/1038227496/34.

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Reid, Brian. "Energy Flow in a Floodplain Aquifer Ecosystem." The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-05232007-165824/.

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We developed an energy budget to identify energy sources for the invertebrate community of a large 20 km2 floodplain aquifer, based on biomass distributions, organismal respirometry, in situ community respiration, mesocosm and microcosm experiments, stable isotopes and invertebrate gut contents. The invertebrate respiration scaling exponent was 0.474 (+/- 0.068, 95% CI) across six orders in body mass, which is significantly lower than the ¾ power scaling predicted by metabolic theory. Invertebrate production was dominated by copepods (Diacyclops, Acanthocyclops, Bryocamptus), Stygobromus amphipods, and amphibiont stoneflies, and ranged from 26.9 to 4200 mg C/m3 sediment/year. Production and density showed a U-shaped response to dissolved oxygen (high production at both low and high oxygen concentrations). Production declined exponentially with depth for most sites, but at sites with orthograde oxygen profiles there was an exponential increase at the oxycline. Aerobic microbial community production ranged from 1210 to 2020 mg C/m3 sediment/year, also showing a U-shaped response to oxygen. System respiratory quotient (RQ) ranged from ≈ 0 to 9.5, indicating a significant contribution of anaerobic production to system energy flow. We documented multiple lines of evidence for DOC (soil, river) and buried POM carbon sources, however POM was by far the largest carbon reservoir in the aquifer at ≈ 108 (to 1010) mg C/ m3 sediment. Energy from POM breakdown was the only source sufficient to explain microbial and invertebrate production. Carbon stable isotope signatures showed strong levels of depletion for invertebrates (δ13C -25 to -70). These results suggest a significant anaerobic subsidy of aerobic food webs in the subsurface, and a potential methane subsidy of 10% to 99% of invertebrate energy flow. Oxygen showed high, non-random, spatial and temporal variation across the aquifer, with a large scale decline in oxygen along the axis of the floodplain, and distinct hotspots of low oxygen. Low oxygen hotspots corresponded with migration of stonefly nymphs 100s of meters into the aquifer. The U-shaped responses and biogeochemical trends suggest a major threshold at bulk oxygen concentrations of 3-5 mg/l. Collectively, these findings indicate the role of dissolved oxygen as a key variable in groundwater ecosystems.

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Wangai, Peter Waweru [Verfasser]. "Mapping and assessment of ecosystem services to improve resource management and human wellbeing in data-scarce peri-urban ecosystems / Peter Waweru Wangai." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1140054120/34.

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Wangai, Peter W. [Verfasser]. "Mapping and assessment of ecosystem services to improve resource management and human wellbeing in data-scarce peri-urban ecosystems / Peter Waweru Wangai." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1140054120/34.

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Yamada, Masahiro S. M. Massachusetts Institute of Technology. "The ecosystem of renewable energy shift and its future dynamics." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118506.

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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 87-89).
Substituting non-renewable energy for renewable energy plays an important role for our sustainability, which is the common goal for human beings. However, several strategies by governments and companies exist to make this shift, because the priority of each strategy mainly depends on the relative costs and their regulations, which makes this shift complicated. This paper describes a model of the common causal loop diagram and applies it to three cases. Additionally, by building stock and flow model, the future dynamics are simulated by System Dynamics. Based on the casual loop diagram analysis, the renewable shift makes three phases. The first phase is making an ecosystem of renewables initiated by political support or guideline such establishing a low generation cost and making the power grid system flexible enough to accept renewables. The second phase is pushing the energy mix by private investment to capture the economic benefit including reducing electric bills with low-cost renewable energy, the merit of reputation and sustainability of business. The third phase aims at meeting the political target of the energy mix by political strategies, such as tax exemptions, subsidies and obligations for companies. Stock and flow model of System Dynamics is applied for the future of the Japanese renewable shift cases to illustrate which compositions of the casual loop are the key causes for dynamics. At first, the relative cost triggers the renewable shift not only for companies but also for utilities. After that, the difference of the energy mix of a company and its target decides how much the energy mix increases each year. These two factors decide the intensiveness of investment of a company, even though the relative cost is not an internal factor. Also, the capacity mix of a utility deals with the speed of the renewable shift.
by Masahiro Yamada.
S.M. in Engineering and Management

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Orr, Kyla Kathleen. "Predicting the ecosystem effects of harvesting beach-cast kelp for biofuel." Thesis, University of the Highlands and Islands, 2013. https://pure.uhi.ac.uk/portal/en/studentthesis/predicting-the-ecosystem-effects-of-harvesting-beachcast-kelp-for-biofuel(82d8913a-164a-4e21-b61b-9f83b462b079).html.

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Beach‐cast kelp (principally Laminaria spp.), known as macroalgal wrack, has been suggested as a feedstock for biofuel. However, to be extracted sustainably it is necessary to understand its ecological role and predict the impacts of its removal. Field‐based observations combined with food web modelling were used to predict the ecosystem effects of removing wrack from beaches of the Uists, western Scotland. Beaches with wrack were associated with enriched benthic infauna (polychaetes) on the lower shore, and wrack mounds supported abundant macroinvertebrates (mainly Diptera larvae and oligochaetes); with some of the highest biomasses reported globally for beaches. These fauna are valuable prey to shorebirds, as demonstrated by a strong positive relationship (R2 = 0.82) between wader abundances and the percentage cover of wrack on beaches. Inshore, drifting macroalgae was associated with elevated abundances of detritivorous hyperbenthic fauna (mysids, isopods and gammarid amphipods). In addition, the volume of drifting macroalgae inshore was a significant predictor (along with physical beach characteristics) for the abundance of decapods and fish. Food web models and network analysis indicated that beaches which accumulate wrack had a greater diversity of trophic links and more functional redundancy, making their food webs more resilient to perturbations. Such perturbations may include stressors induced by climate change, such as increased erosion of sediments during storms, elevated atmospheric and sea surface temperatures and elevated CO2 concentrations. Model simulations of wrack harvesting predicted an immediate decline in primary consumers in direct proportion to the quantity of wrack removed, and a slow decline in shorebirds in response to reduced prey. Primary consumers were predicted to recover to their pre‐harvest biomasses within 1 to 2 years regardless of harvesting intensity, but recovery times for shorebirds were an order of magnitude longer, and increased with harvesting intensity. Harvesting more than 50% wrack predicted a ‘collapse’ in wader populations within 25 years, and recovery times of 45‐60 years were estimated if >70% wrack was removed. The findings of this thesis suggest wrack provides essential food and shelter to coastal fauna, and its large‐scale removal would have significant negative impacts to the ecosystem functioning.

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Hooper, Tara Louise. "Evaluating the costs and benefits of tidal range energy generation." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619144.

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Tidal barrages could contribute to mitigating climate change, but their deployment is not without potential welfare costs attributable to the degradation of ecosystem services. Economic valuation of natural resources provides a common metric for quantifying the disparate costs and benefits of barrage construction in a way that provides transparency when trade-offs are considered. However, very little is currently known about the value of environmental impacts associated with tidal barrages. Using the Taw Torridge estuary in North Devon as a case study, this research proposes an Environmental Benefits Assessment methodology that supports application of the ecosystem services concept to local environmental impact appraisal, and facilitates economic valuation. This methodology is novel in that it evaluates benefits, as opposed to services, and considers a comprehensive suite of benefits in a single assessment: an approach rarely attempted in practice, but essential if ecosystem services approaches are to fully support resource management needs. The subsequent empirical valuation uses stated preference techniques to examine the different ways people use and value the estuary ecosystem, determine how strongly they rank different costs and benefits of tidal barrages, and elicit willingness to pay (WTP) to reduce the habitat loss resulting from a tidal barrage development. The study provides the first empirical valuation of UK estuarine mudflats, but makes a further contribution to the environmental economics discipline by deploying both contingent valuation and choice experiment methods. Additionally, a novel application of the Analytic Hierarchy Process (AHP) is used to examine the consistency of WTP with expressed preferences for habitat protection in relation to other barrage attributes. The alternative stated preference techniques result in comparable WTP values and the importance attached to habitat loss (as measured by the AHP) is strongly associated with WTP and also with its scope sensitivity, indicating that WTP is largely driven by environmental preferences.

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Gately, Mark. "Dynamic Modeling to Inform Environmental Management: Applications in Energy Resources and Ecosystem Services." ScholarWorks @ UVM, 2008. http://scholarworks.uvm.edu/graddis/89.

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Two original computer simulation models are presented in this thesis. Although these models differ in their temporal, spatial, and structural dimensions, they are unified by a common purpose: to build quantitative understanding of environmental resources and better inform their future management. According to the U.S. Department of the Interior’s Minerals Management Service, there are significant undiscovered reserves of oil and natural gas located in the Gulf of Mexico Outer Continental Shelf region. While the existence of these energy resources is critical to the nation’s future economic well-being, of equal importance is the amount of already extracted energy that will be required to deliver the new fuel to society in a useful form; the difference between the two quantities is the net energy supply. “Energy return on investment” (EROI) is an indicator of the net productivity of an energy supply process; specifically, it is the ratio of gross energy production to total, direct plus indirect, energy cost. Chapter 1 describes a dynamic model designed to calculate the EROI of offshore energy extraction in the U.S. Gulf of Mexico from 1985 to 2004 under differing assumptions regarding energy cost and technology. In 2004, the EROI of the process is estimated to range from 10 to 25 depending on how comprehensively energy costs are defined. In comparison, the EROI of U.S. onshore petroleum extraction in the 1930s was at least 100. Ecosystem services are those functions of ecosystems that support, directly or indirectly, human welfare. Although interest in ecosystem services has surged in recent decades and is currently still on the rise, these phenomena have yet to be universally quantified. The current Multi-scale, Integrated Models of Ecosystem Services (MIMES) project is an ambitious attempt to do so through dynamic, spatially explicit modeling. As a part of this broad initiative, Chapter 2 details the development and testing of a model designed to measure and map the ecosystem service “water regulation” at multiple scales. The model is an extension of the well known and widely used “runoff curve number” method originally developed by the U.S. Department of Agriculture; it is applied to the Winooski watershed (Vermont, U.S.A.) and to the entire globe.

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Brinck, Katharina. "Information Entropy and Ecological Energetics : Predicting and Analysing Structure and Energy Flow in Ecological Networks applying the Concept of MaxEnt." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-89600.

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Ecological networks are complex systems forming hierarchical structures in which energy and matter is transferred between the network’s compartments. Predicting energy flows in food webs usually involves complex parameter-rich models. In this thesis, the application of the principle of maximum entropy (MaxEnt) to obtain least biased probability distributions based on prior knowledge is proposed as an alternative to predict the most likely energy flows in food webs from the network topology alone. This approach not only simplifies the characterisation of food web flow patterns based on little empirical knowledge but can also be used to investigate the role of bottom-up and top-down controlling forces in ecosystems resulting from the emergent phenomena based on the complex interactions on the level of species and individuals. The integrative measure of “flow extent”, incorporating both bottom- up and top-down controlling forces on ecosystems, is proposed as a principle behind ecosystem evolution and evaluated against empirical data on food web structure. It could be demonstrated that the method of predicting energy flow with the help of MaxEnt is very flexible, applicable to many different setting and types of questions in ecology, and therefore providing a powerful tool for modelling the energy transfer in ecosystems. Further research has to show in how far the most likely flow patterns are realised in real-word ecosystems. The concept of flow extent maximisation as a selection principle during ecosystem evolution can enhance the understanding of emergent phenomena in complex ecosystems and maybe help to draw a link between thermodynamics and ecology.

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Buechler, Stephanie, Debashish Sen, Neha Khandekar, and Christopher Scott. "Re-Linking Governance of Energy with Livelihoods and Irrigation in Uttarakhand, India." MDPI AG, 2016. http://hdl.handle.net/10150/622500.

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Hydropower is often termed "green energy" and proffered as an alternative to polluting coal-generated electricity for burgeoning cities and energy-insecure rural areas. India is the third largest coal producer in the world; it is projected to be the largest coal consumer by 2050. In the Himalayan state of Uttarakhand, India, over 450 hydroelectric power schemes are proposed or are under development. Hydropower projects ranging from micro hydro (run-of-the-river systems with generating capacity up to 100 kW) to large reservoirs (storage systems up to 2000 MW) such as the Tehri Dam are in various stages of planning, construction or implementation. Run-of-the-river hydropower projects are being developed in Uttarakhand in order to avoid some of the costs to local communities created by large dams. Stakeholders in this rapid hydropower expansion include multiple actors with often diverging sets of interests. The resulting governance challenges are centered on tradeoffs between local electricity and revenue from the sale of hydropower, on the one hand, and the impacts on small-scale irrigation systems, riparian-corridor ecosystem services, and other natural resource-based livelihoods, on the other. We focus on the Bhilangana river basin, where water dependent livelihoods differentiated by gender include farming, fishing, livestock rearing and fodder collection. We examine the contradictions inherent in hydropower governance based on the interests of local residents and other stakeholders including hydropower developers, urban and other regional electricity users, and state-level policymakers. We use a social justice approach applied to hydropower projects to examine some of the negative impacts, especially by location and gender, of these projects on local communities and then identify strategies that can safeguard or enhance livelihoods of women, youth, and men in areas with hydropower projects, while also maintaining critical ecosystem services. By assessing the Bhilangana basin case, we also offer hydropower-livelihoods-irrigation nexus lessons for headwater regions across the Himalayas and globally.

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Bertram, Christine [Verfasser]. "Essays on the Economics of Ecosystems and Biodiversity / Christine Bertram." Kiel : Universitätsbibliothek Kiel, 2015. http://d-nb.info/1067842020/34.

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Schmidt, Stefan [Verfasser], Ralf [Gutachter] Seppelt, and Thomas [Gutachter] Koellner. "Ecosystem service databases and their contribution to mainstream ecosystem service information / Stefan Schmidt ; Gutachter: Ralf Seppelt, Thomas Koellner." Halle (Saale) : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2019. http://d-nb.info/1210728826/34.

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Asgari, Aliakbar. "Simulation of Collective Intelligence of a Multi-Species Artificial Ecosystem Based on Energy Flow." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31796.

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Collective intelligence (CI) emerges from local coordination, collaboration and competition among the individuals within a social group. CI mainly results in a global intelligent behavior. One of the fundamental interactional channels within a CI system is energy flow. Each agent within an artificial or physical ecosystem must absorb energy in order to survive, evolve, breed, and reshape its local environment. In addition because the energy resources are limited in the environment, each agent has to compete with other agents to reach the required level of energy. Understanding the internal energy flow can potentially provide a deep insight into internal activities and external emergent behaviors of a given complex system. This study proposes a stochastic scheme for modeling a multi-species prey-predator artificial ecosystem with two levels of food chain. This will enable us to investigate the influence of energy flow on the ecosystem’s lifetime. The proposed model consists of a stationary hosting environment with dynamic weather condition and fruit trees. The inhabitants of this ecosystem are herbivore and carnivore birds each consisting of species. In our model, the collective behavior emerges in terms of flocking with more added rules consist of breeding, competing, resting, hunting, escaping, seeking and foraging behaviors. Using multi-species scheme, we define the ecosystem as a combination of prey and predator species with inter-competition among species within same level of food chain and intra-competition among those belonging to different levels of food chain. Furthermore, in order to model the energy within the ecosystem, some energy variables as functions of behaviors are incorporated in to the model. Finally, a simulation and visualization structure for implementing the proposed model is developed in this study. The experimental results of 11,000 simulations analyzed by Cox univariate analysis and hazard function suggest that only five out of eight behaviors can statistically significant influence the ecosystem’s lifetime. Furthermore, the results of survival analysis show that out of all possible interactions among energy factors, only two of them, interaction between flocking and seeking energies, and interaction between flocking and hunting energies, have statistically significant impact on the system’s lifetime. In addition, software implementation of the proposed framework validates the stability of simulation and visualization architecture. At last regression results using Nelson-Aalen cumulative hazard function and Cox-Snell variable and scaled Schoenfeld residuals test strongly validate our experimental results. To the best of our knowledge, there are three contributions in this research: First, the high level of complexity in the structure of the proposed model in comparison with the other systems which mostly contains only one species of prey, one species of predator and a kind of resource. While this study introduces two species of prey, capability of competition among species, dynamic weather condition with two element of wind and rain and dynamic resources, various behavioral rules such as escaping, breeding, hunting, resting, etc. Energy flow analysis within an artificial ecosystem is the second contribution. To the best of author’s knowledge there is no similar comprehensive model in the previous literature that investigates the life span of a stochastic multi-species predator-prey artificial ecosystem based on energy flow using Survival Analysis method. Lastly, the simulation results show that the flocking and seeking energy and flocking and hunting energy interactions are the most significant interactions which match with the Thompson iii et al. [ 65] observations in the real life. Their findings indicate that in the real life, birds use flocking behavior for better movement, more efficient food searching and social learning. Flocking motion also decrease predation risk as much as the flock size increases.

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Bracewell, Kathryn Vanessa. "An exploration of new methods to assess energy availability in the English oak (Quercus robur)." Thesis, Cranfield University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323884.

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Kumin, Enid C. "Ecosystem-Based Management and Refining Governance Of Wind Energy in the Massachusetts Coastal Zone: A Case Study Approach." Antioch University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1438439831.

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Taghvaeian, Saleh. "Water and Energy Balance of a Riparian and Agricultural Ecosystem along the Lower Colorado River." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/949.

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Spatially-distributed water consumption was modeled over a segment of the Lower Colorado River, which contains irrigated agricultural and Tamarisk-dominated riparian ecosystems. For the irrigation scheme, distributed evapotranspiration data were analyzed in conjunction with point measurements of precipitation and surface flow in order to close daily and annual water balance. The annual closure error was less than 1% of the total water diversion to the area. In addition, it was found that the soil water storage component of the water balance cannot be neglected if the analysis is performed over time frames shorter than annual (e.g. growing season). Water consumption was highly uniform within agricultural fields, and all the full-cover fields were transpiring close to their potential rates. Mapping several new and existing drainage performance indicators showed that neither soil salinization nor water-logging would be of concern in this irrigation scheme. However, the quality of high-volume return flow must be studied, especially since the degraded water quality of the western US rivers is believed to act in favor of the invasive riparian species in outcompeting native species. Over the Tamarisk forest, the remotely-sensed evapotranspiration estimates were higher than the results of an independent groundwater-based method during spring and winter months. This was chiefly due to the fixed satellite overpass time, which happened at low sun elevation angles in spring and winter and resulted in a significant presence of shadows in the satellite scene and consequently a lower surface temperature estimate, which resulted in a higher evapotranspiration estimate using the SEBAL model. A modification based on the same satellite imagery was proposed and found to be successful in correcting for this error. Both water use and crop coefficients of Tamarisk estimated by the two independent methods implemented in this study were significantly lower than the current approximations that are used by the US Bureau of Reclamation in managing the Lower Colorado River. Studying the poorlyunderstood stream-aquifer-phreatophyte relationship revealed that diurnal and seasonal groundwater fluctuations were strongly coupled with the changes in river stage at close distances to the river and with the Tamarisk water extraction at further distances from the river. The direction of the groundwater flow was always from the river toward the riparian forest. Thus the improved Tamarisk ET estimates along with a better understanding of the coupling between the river and the riparian aquifer will allow the Bureau of Reclamation to re-asses their reservoir release methodology and improve efficiency and water savings.

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Bray, Laura. "Preparing for offshore renewable energy development in the Mediterranean." Thesis, University of Plymouth, 2017. http://hdl.handle.net/10026.1/10099.

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The development of offshore wind farms and marine renewable energy devices in the Mediterranean is central to both national, and international, energy strategies for countries bordering the Mediterranean Sea. The ecological impacts of marine renewable energy development in the Mediterranean region, although essential for policy makers, are as yet unknown. The Northern Adriatic is identified as a plausible site for offshore wind farm development. Using the wider region (Adriatic and Northern Ionian) as a case study, this thesis examines the likely impact to the marine environment if an offshore wind farm is established. Site suitability, based on wind speed, bathymetry, and larvae connectivity levels are investigated along with the plausibility of the turbines operating as artificial reefs in the area. As offshore wind farms may alter the larval connectivity and supply dynamics of benthic populations, a connectivity map was constructed to identify areas of high and low connectivity in the Adriatic Sea. The Puglia coast of Italy is a likely larval sink, and displays some of the highest connectivity within the region, suggesting potential inputs of genetic materials from surrounding populations. Considering offshore wind farms could operate as artificial reefs, an in-situ pilot project was established to simulate the presence of wind turbines. Macroinvertebrates colonized the new substrata within the first few months but were lower in abundance when compared to a natural hard substrata environment. Time, turbine location, and the material used for turbine construction all affected the macro-invertebrate communities. In addition, fish abundances, and diversity were lower around the simulated OWF foundations in comparison to a natural hard substrata environment, and no increases in fish abundance occurred around the simulated turbines when compared to reference sites of soft substrata. This observation was validated with the use of an ecosystem modelling software (Ecopath with Ecosim), which simulated the overall ecosystem level impacts that would occur if 50 offshore monopile wind turbines were introduced to the Northern Ionian and colonized by macroinvertebrate communities. When compared to the baseline scenario (no simulated introduction of an OWF), the introduction of new habitat had no discernible impacts to the structure or functioning of the marine ecosystem. Noticeable changes to the ecosystem were only apparent if fishing restrictions were enforced in parallel with the simulated offshore wind farm; the ecosystem appears to become more structured by top down predation. In addition seabirds are also impacted by the reduction of fishing discards as a food source. These results are the first attempt to quantify the suspected benefits of offshore wind farms operating as de-facto marine protected areas.

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Niutanen, Ville. "Industrial ecosystem case studies : the potential of material and energy flow roundput in regional waste management /." Joensuu : Joensuun yliopisto, 2005. http://www.loc.gov/catdir/toc/fy0608/2005390556.html.

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Kurc, Shirley Anne. "Dynamics and controls of ecosystem scale water, carbon, and energy cycling at semiarid grassland and shrubland." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219049.

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Gbossou, Christophe. "Mise en place d’un pôle intégré d’excellence pour les énergies renouvelables. Cas de l’énergie solaire en Afrique de l’Ouest." Thesis, Saint-Etienne, EMSE, 2013. http://www.theses.fr/2013EMSE0694/document.

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L’objectif du travail est la mise en place d’un pôle intégré d’excellence pour l’énergie solaire en Afrique de l’Ouest. Trois pays y ont été identifiés comme territoires d’expérimentation (Burkina Faso ; Côte d’Ivoire ; Sénégal). Les enquêtes de terrain dans ces territoires suivies d’une analyse de filière a permis de mettre en évidence les interactions entre les acteurs de la filière solaire dans les trois pays (pouvoirs publics ; recherche et formation ; entreprises ; société civile ; utilisateurs). La réalisation de matrices d’influences directes à partir des résultats de l’analyse de la filière solaire dans les pays a permis de comprendre le faible niveau de relations entre les acteurs interdépendants. Les résultats révèlent que les pouvoirs publics demeurent les acteurs dominants de la filière solaire dans les trois pays, malgré la faiblesse de leur volonté. Les entreprises privées et les organisations non gouvernementales sont des acteurs relais (entre les pouvoirs politiques et les utilisateurs) qui jouent un rôle d’installation d’équipements solaires et de développement de projets surtout en milieux ruraux. Les utilisateurs (consommateurs) de la filière solaire sont des acteurs « dominés » qui n’ont pas d’influence sur les autres acteurs notamment les pouvoirs politiques. La recherche et la formation dont les résultats se limitent à des formations théoriques ou des expérimentations non diffusées restent des acteurs isolés. Le pôle intégré construit permet de stabiliser, régulariser et faire circuler entre eux les connaissances produites et les capacités développées par les acteurs en interactions au sein d’un écosystème
The purpose of this thesis is the building an integrated excellence pole for solar energy in West Africa. Three countries have been identified as areas for experimentation (Burkina Faso; Cote d’Ivoire; Senegal). Field surveys in these territories and sector analysis allow highlighting the interactions among the solar sector actors in the three countries (political field, research and training, business, civil society, users). The realization of direct influence matrices from the results of solar energy sector analysis in the countries helped us to understand the low level of relationship among interdependent stakeholders.The results show that the public authorities are still the dominant players, despite the weakness of their willingness. Private companies and non-governmental organizations have a liaison role playing an essential task of solar equipment installation and projects development especially in rural areas. The users of the solar sector are dominated players without influence on the other players especially the public authorities. The research actors clearly appear as isolated: Their results are generally limited to theoretical courses, the conduct of experiments and prototypes that rarely reach public release phase. The constructed pole allows to stabilize, to settle and to make the produced knowledge circulate and the capacities developed by the actors in interaction within an ecosystem

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Sagerman, Josefin. "Marine seaweed invasions : Impacts and biotic resistance in native ecosystems." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116788.

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Marine seaweeds constitute one of the most productive plant systems known on Earth and a rich fauna including juvenile fish and crustaceans is dependent on the habitats they form. Human influence on marine costal ecosystems has resulted in large scale changes to the abundance and distribution of species, where species introductions constitute an obvious part. The aims of this thesis were to 1) explore how non-native seaweeds impact on ecosystem functions (primary production and decomposition), and 2) study how interactions between non-native seaweeds and native communities affect invasion success. I used a combination of laboratory assays, outdoor mesocosms and field experiments. Paper I and II revealed that the impact on ecosystem functions were substantially different depending on the identity of the invader. The highly successful non-native red alga Heterosiphonia japonica had a large effect on community productivity. Due to the rapid growth of the invader, the primary production increased by more than four times in mixed species communities with the invader compared to communities with only native species. In contrast, the morphologically similar and equally successful non-native red alga Bonnemaisonia hamifera grew slowly and had no effect on community production. But B. hamifera produces a potent defense compound that deters native herbivores and reduces the growth of micro-organisms. As a direct or indirect effect of this chemical defense, the litter from B. hamifera decomposed considerably slower compared to native seaweed litter. Rapid growth and defense against predation are likely important in explaining how the two invaders have become successful in the invaded range. These results show that traits related to invasion success may determine impacts on native communities. Paper III shows that the rapidly growing invader H. japonica is avoided as food by native herbivores, which likely enables the invader to survive during colder seasons with sub-optimal growth conditions. In paper IV I found that competition from the native brown alga Fucus vesiculosus decreased growth of the non-native congener Fucus evanescens. Native herbivores caused more damage to the native competitor but it did not relieve F. evanescens from competitive pressure. Several native brown algae grow in the niche of F. evanescens, which may explain why the species only is growing sparingly in the invaded range. The results indicate that competition with native seaweeds have potential to reduce the success of non-native seaweeds in the new range. In summary, this thesis shows that non-native seaweeds differ strongly in their effect on ecosystem functions. Knowledge of which traits are present among abundant non-native species and how these traits relates to different effects may enable us to gain a better understanding of invasion impacts on native communities. The thesis also highlights that competitive interactions can be of importance for invasion success in seaweed communities.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.

Alien-native trophic interactions: consequences for invasion success and ecosystem effects of invasions

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Perkin, Elizabeth Katharine [Verfasser]. "The effects of artificial light at night on stream ecosystems / Elizabeth Katharine Perkin." Berlin : Freie Universität Berlin, 2013. http://d-nb.info/1034073923/34.

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Strunz, Sebastian [Verfasser], and Stefan [Akademischer Betreuer] Baumgärtner. "Ecosystem resilience as an economic insurance / Sebastian Strunz. Betreuer: Stefan Baumgärtner." Lüneburg : Universitätsbibliothek der Leuphana Universität Lüneburg, 2012. http://d-nb.info/1034194852/34.

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Rouse, Sally. "Quantifying benthic secondary productivity on artificial structures : maximising the benefit of marine renewable energy devices." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231790.

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Marine renewable energy developments (MRED) will result in large quantities of infrastructure being deployed in coastal habitats, and the localised exclusion of fishing. The ecological consequences of this scale of deployment are largely unknown, particularly for benthic species. Infrastructure has the capacity to act as artificial reefs (ARs), providing novel habitat, and this may viewed as a benefit of MRED, or a means to mitigate the exclusion of fishing. At present, the functioning of AR ecosystems remains poorly understood. As a measure of ecosystem function, secondary productivity can be used to assess the implications of MRED. The lack of suitable methodology, deployable at relevant scales within time and/or cost constraints, has limited benthic secondary productivity (BSP) quantifications on ARs. Techniques to measure potential BSP and particle flux were developed and applied to the Loch Linnhe Artificial Reef (functionally similar to scour protection material). Variations in BSP and mobile epifaunal densities on, and between, structures in different environments were quantified. Reefs exposed to intermediate current had the highest potential productivity. The BSP on internal areas of structures contributed to the total productive output, but the relative contribution varied according to reef location and design. BSP was primarily determined by particle supply, but the response was not consistent among locations. Mobile epifaunal densities related to reef location, but not reef design, and were highest on reefs in the deepest water and exposed to the fastest currents. The evidence presented in this thesis highlights the need to account for the receiving environment when predicting the ecological consequences of MRED, or when modelling the productive capacity of structures. Such information can be used to suggest modifications to proposed or existing structures in order to maximise their benefit to coastal ecosystems.

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Pacetti, Tommaso Verfasser], and Boris [Akademischer Betreuer] [Schröder. "Investigating water-land-ecosystems nexus for watershed integrated management / Tommaso Pacetti ; Betreuer: Boris Schröder-Esselbach." Braunschweig : Technische Universität Braunschweig, 2018. http://d-nb.info/1175387568/34.

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Regester, Kurt Joel. "Ecosystem significance of ambystomatid salamanders : energy flow, habitat subsidies, and trophic interactions associated with their complex life cycles /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1342728871&sid=9&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Lee, Heera [Verfasser]. "Analyzing trade-offs between ecosystem services in multi-functional landscapes / Heera Lee." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1155922808/34.

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Joiner, David Wayne. "Energy and mass fluxes over a boreal forest in northern Manitoba, net ecosystem exchange and energy balances for the boreas nsa young jack pine and fen sites." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ38310.pdf.

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Handiso, Bisrat Woldemichael. "The challenges and Opportunities of the Grand Renaissance Dam for sustainable Energy - Water - Food - Ecosystem services Nexus in Ethiopia." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-360827.

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Ethiopia has been challenged by multidimensional poverty. However, it has the potential to minimize the threat through an integrated multipurpose development process. In this regard, hydropower has a significant role to reduce energy poverty and enhance the multipurpose use of natural resources efficiency. Hydropower is a source of clean, sustainable and renewable energy. It has a contribution to reducing carbon emission and maintaining environmental sustainability. In Ethiopia, it is the major source of electricity. The country is rich in natural resources, including water to produce energy, however, electricity supply is still uncertain. The data shows that the country has the potential to produce 50,000 MW energy from water resources. Yet, it exploited 3,822 MW in 2018, approximately 7.6 % of its potential. Moreover, the country faces issues with energy security. Additionally, water and food supply also face an uncertain future. In this case, the country has planned the growth and transformation plan I and II for 2015 and 2020 to increase the energy production to 10,000 MW and 17,000 MW energy respectively. Consequently, the government launched different multipurpose hydropower plant projects. This project focuses on the multipurpose use of the Grand Ethiopian Renaissance Dam, particularly for the sustainable energy-water-food-ecosystem service nexus at the national level. I applied the combination of methods such as the energy-water-food-ecosystem nexus, the SWOT analysis and the sustainability assessment as they are suitable for the complexity of such a project. Indeed, the GERD has benefits for the country in producing renewable and clean energy, generating income and increasing the water storage capacity at the national level. However, the project neglected the values of ecosystem services integration with the dam and its sectors. As a result, the dam affected the existed terrestrial biodiversity and ecosystem. Therefore, the GERD had not been the well-prepared plan that considers institutional cooperation and sectoral integration to use for multipurpose function and its sustainability. In these regards, unless the dam to take proper management of the project and natural resources, the hydropower plant would not have been generating sustainable energy production.

The paper shows that how to use the reservoir hydropower plant for multipurpose, such as for energy, water, food, ecosystem services integration at local level

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Thienelt, Thomas Sebastian Verfasser], Manfred [Akademischer Betreuer] [Frühauf, Georg [Akademischer Betreuer] Guggenberger, and Dean E. [Akademischer Betreuer] Anderson. "Net ecosystem exchange of CO2 and energy fluxes of turf in the Denver urban ecosystem and an adjacent tallgrass prairie / Thomas Sebastian Thienelt. Betreuer: Manfred Frühauf ; Georg Guggenberger ; Dean E. Anderson." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2015. http://d-nb.info/1072410346/34.

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Grossmann, Malte [Verfasser], and Volkmar [Akademischer Betreuer] Hartje. "Economic Valuation of Wetland Ecosystem Services.Accounting for wetland ecosystem service benefits in cost benefit analysis of river basin management options with case studies from the Elbe River Basin. / Malte Grossmann. Betreuer: Volkmar Hartje." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1021976709/34.

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López, Muñoz Ignacio Francisco. "Optimal spatial arrangements of three ecosystems: microalgae pond, anaerobic digester and aerobic wastewater treatment plant." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/139852.

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Ingeniero Civil en Biotecnología
Ingeniero Civil Químico
Actualmente existen diversos problemas medioambientales, dos de ellos corresponden a la futura crisis energética, debido al agotamiento de los combustibles fósiles, y a la existencia de aguas residuales con altas concentraciones de nitrógeno y carbono. Un microorganismo llamado microalga podría ser una potencial solución a estos problemas, ya que éstos consumen nitrógeno y carbono para acumular lípidos en su medio intracelular, el cual posteriormente es procesado para producir biocombustibles. Sin embargo, la producción de energía a partir de microlagas es aún muy cara, es por eso que se debe optimizar este proceso, en este trabajo se abordará la estrategia de optimización a través del acoplamiento de ecosistemas, los cuales corresponden a: Piscina de microalgas (PM), digestor anaeróbico (DA) y una planta de tratamiento de aguas (PTA). El objetivo general de esta investigación es encontrar el arreglo espacial óptimo entre ellos. Se diseñaron y calibraron modelos matemáticos simples para el ecosistema PM y PTA. La calibración se llevó a cabo usando las curvas de nitrógeno y de demanda química de oxígeno (DQO) en paralelo, con una suma de errores de 22.5% para el PM y de 38.5% para el PTA. Los parámetros obtenidos son comparables a los encontrados en la literatura. Los ecosistemas fueron acoplados a través de sus flujos de DQO y de nitrógeno, y las siguientes funciones objetivo fueron definidas: 1) Maximizar el metano producido 2) Maximizar la energía total producida y 3) Maximizar las ganacias obtenidas gracias al valor del metano y de la biomasa producida. Además, fueron consideradas restricciones medioambientales, tales como la concentración de nitrógeno y la DQO en la salida del sistema. Si lo que se maximiza es el metano, se obtienen 99.96 [mol]. El reactor anaeróbico es el más grande y recibe la alimentación más alta, el CH4 generado corresponde al 72.4% del máximo teórico. En este caso, el arreglo espacial no puede ser presentado como una cadena de etapas porque el diagrama de flujos obtenido es uno circular y por lo tanto el orden entre cada ecosistema es irrelevante para el proceso. Si la ganacia y la energía total producida son maximizadas, se obtuvo 343.6 US$ y 115.53 [kWh], respectivamente. El ecosistema de tratamiento de aguas recibe la alimentación más alta, el cual produce el mayor beneficio económicos y la mayor producción de energía. El metano producido es un 21% del máximo teórico. En ambos casos, el arraglo espacial obtenido son iguales, debido a la presencia de mínimos locales y a la similtud de las funciones objetivo. Además, es posible concluir que el primer paso del proceso debiese ser el ecosistema PTA, luego el DA y finalmente el PM. Así, se pudo cumplir el objetivo general de este trabajo. Finalmente, la metodología usada es capaz de cumplir los objetivos planteados, incluso es posible escalar el problema agregando otros ecosistemas o usarla en otras aplicaciones." "In recent years several environmental problems have come about, two of them are an energy crisis as a result of fossil fuel exhaust and the waste water created with high nitrogen and carbon concentrations. A potential solution of the aforementioned problems is contained in the properties of microalgae, which is a microorganism that can accumulate lipids in its intracellular medium. These lipids can be processed and converted into biofuel by allowing microalgae to consume nitrogen and an organic source from the medium. However, energy production from microalgae is too expensive in comparison with fossil fuel and thus there is a need to optimize this process. The strategy of optimizing by coupling ecosystems will be carried out in this work. The ecosystems that will be coupled are: Microalgae pond (MP), anaerobic digester (AD) and wastewater treatment plant (WWT). The general objective of this research is to find the optimal spatial arrangement among them through mathematical modelling. Simple mathematical models were designed and calibrated to MP and WWT ecosystem. Calibrations were carried out using nitrogen and chemical oxygen demand (COD) curves in parallel with a sum error of 22.5% in MP and 38.5% in WWT. Obtained parameters are similar to ones found in previous literature. Ecosystem were coupled through COD and nitrogen flows and the following objectives functions were defined: 1) Maximize methane produced 2) Maximize total energy produced and 3) Maximize profit due to the value of methane and microalgae biomass produced. Environmental constraints were considered, such as nitrogen and COD because they are in the output. When the methane produced was maximized it reached 99.96 [mol]. The anaerobic reactor has the biggest size, it receives the highest input flow, and CH4 generated is the 72.4% of maximum theoretical methane production. This result determined that the spatial arrangement can not be summarized by a chain of processes since the flowsheet obtained is a circular one and thus the order is irrelevant for the process. When profit and total energy produced are maximized, it was obtained 343.6 US$ and 115.53 [kWh]$ respectively. Waste water ecosystem received the biggest input flow, which produced the majority of amount of revenues and energy. Methane produced is equal to 21% of maximum theoretical. In both cases, the spatial arrangements obtained are equals due to the presence of local minima and the similarity in the objective function. These calculations allow to conclude the best order of the ecosystems: WWT, AD, and finally MP. Finally the methodology is enough to reach the objectives of this work, even it is possible to scale the system adding more than one ecosystem or using this methodology in other fields.

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Koch, Jennifer [Verfasser]. "Modeling the impacts of land-use change on ecosystems at the regional and continental scale / Jennifer Koch." Kassel : Kassel University Press, 2010. http://d-nb.info/1016968442/34.

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Bicking, Sabine [Verfasser]. "Quantification and mapping of regulating and provisioning ecosystem services in Schleswig-Holstein, Germany / Sabine Bicking." Kiel : Universitätsbibliothek Kiel, 2019. http://d-nb.info/1191179907/34.

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Aggett, Jonathan Edward. "Financial Analysis of Restoring Sustainable Forests on Appalachian Mined Lands for Wood Products, Renewable Energy, Carbon Sequestration, and Other Ecosystem Services." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/36096.

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Abstract:

Public Law 95-87, the Surface Mining Control and Reclamation Act of 1977 (SMCRA), mandates that mined land be reclaimed in a fashion that renders the land at least as productive after mining as it was before mining. In the central Appalachian region, where prime farmland and economic development opportunities for mined land are scarce, the most practical land use choices are hayland/pasture, wildlife habitat, or forest land. Since 1977, the majority of mined land has been reclaimed as hayland/pasture or wildlife habitat, which is less expensive to reclaim than forest land, since there are no tree planting costs. As a result, there are now hundreds of thousands of hectares of grasslands and scrublands in various stages of natural succession located throughout otherwise forested mountains in the U.S. The purpose of this study is to develop a framework for understanding/calculating the economic implications of converting these reclaimed mined lands to forests under various silvicultural regimes, and to demonstrate the economic/decision-making implications of an incentive scheme on such a land use conversion. The economic feasibility of a range of land-use conversion scenarios was analyzed for both mixed hardwoods and white pine, under a set of low product prices and under a set of high product prices. Economic feasibility was based on land expectation values. Further, three types of incentive schemes were investigated: 1) lump sum payment at planting (and equivalent series of annual payments), 2) revenue incentive at harvest and 3) payment based on carbon volume.

Mixed hardwood LEVs ranged from -$2416.71/ha (low prices) to $3955.72/ha (high prices). White pine LEVs ranged from -$2330.43/ha (low prices) to $3746.65/ha (high prices). A greater percentage of white pine scenarios yielded economically feasible land-use conversions than did the mixed hardwood scenarios, and it seems that a conversion to white pine forests would, for the most part, be the more appealing option. It seems that, for both mixed hardwoods and white pine, it would be in the best interests of the landowner to invest in the highest quality sites first. For a conversion to mixed hardwood forests, a low intensity level of site preparation seems economically optimal for most scenarios. For a conversion to white pine forests, a medium intensity level of site preparation seems economically optimal for most scenarios.

Mixed hardwoods lump sum payments, made at the time of planting, ranged from $0/ha to $2416.71/ha (low prices). White pine lump sum payments, made at the time of planting, ranged from $0/ha to $2330.53/ha (low prices). Mixed hardwoods benefits based on an increase in revenue at harvest, ranged from $0/ha to $784449.52/ha (low prices). White pine benefits based on an increase in revenue at harvest ranged from $0/ha to $7011.48/ha (high prices). Annual mixed hardwood benefits, based on total stand carbon volume present at the end of a given year, ranged from $0/ton of carbon to $5.26/ton carbon (low prices). White pine benefits based on carbon volume ranged from $0/ton of carbon to $18.61/ton of carbon (high prices). It appears that, for white pine scenarios, there is not much difference between incentive values for lump sum payments at planting, revenue incentives at harvest, and total carbon payments over a rotation. For mixed hardwoods, however, it appears that the carbon payment incentive is by far the cheapest option of encouraging landowners to convert land.
Master of Science

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Förster, Johannes [Verfasser]. "Assessing ecosystem services for informing decision making on sustainable land management under climate change / Johannes Förster." Halle, 2018. http://d-nb.info/1162134313/34.

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Hölting, Lisanne [Verfasser], Anna [Gutachter] Cord, Irene [Gutachter] Ring, and Ralf [Gutachter] Seppelt. "Multifunctionality of landscapes - an ecosystem service perspective / Lisanne Hölting ; Gutachter: Anna Cord, Irene Ring, Ralf Seppelt." Dresden : Technische Universität Dresden, 2021. http://d-nb.info/1236383982/34.

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Hogsden, Kristy Lynn. "Structure and function of food webs in acid mine drainage streams." Thesis, University of Canterbury. School of Biological Sciences, 2013. http://hdl.handle.net/10092/10357.

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Acid mine drainage (AMD) is a significant environmental issue worldwide, which often causes severe contamination and marked species losses in receiving streams. However, little is known about how this stress alters food webs and ecosystem function. I conducted a literature review, which revealed that AMD-impacted streams generally had depauperate benthic communities dominated by a few tolerant species and impaired ecosystem processes. Next, using survey and experimental-based approaches, I investigated food web structure and energy flow in these highly stressed streams, which typically have low pH (< 3), high concentrations of dissolved metals (Al, Fe), and substrata coated with metal hydroxide precipitates, on the South Island, New Zealand. Inputs of AMD caused substantial loss of consumers and reduced the overall number of links between species generating small and simplified food webs, with few invertebrates and no fish. Comparative analysis of food webs from a survey of 20 streams with either anthropogenic or natural sources of acidity and metals, indicated that anthropogenic sources had a stronger negative effect on food web properties (size, food chain length, number of links); an effect driven primarily by differences in consumer diversity and diet. However, the presence of fewer trophic levels and reduced trophic diversity (detected using isotopic metrics), were common structural attributes in AMD-impacted webs along a pH gradient, regardless of impact level. Furthermore, complementary dietary analyses of consumer gut contents and stable isotope signatures (δ13C and 15N) confirmed that primary consumers fed generally on basal resources and that there were few predatory interactions, which reflected low densities of small-bodied chironomids. This suggests that food quantity was unlikely to limit primary consumers but that reduced prey availability may be an additional stressor for predators. In these radically re-structured food webs, trophic bottlenecks were generated at the primary consumer level and energy flow to higher consumers was disrupted. However, streams still retained some limited function, including slow leaf litter breakdown, which provided detrital resources and supported the small food webs. Overall, my findings have furthered our understanding of these highly stressed stream ecosystems by providing new insights into interactions among species and trophic levels that structure food webs and enable function.

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Chen, Cheng Verfasser], Klaus [Gutachter] [Müller, Bettina [Gutachter] Matzdorf, and Thomas [Gutachter] Aenis. "Governmental Payments for Ecosystem Services Programs in China / Cheng Chen ; Gutachter: Klaus Müller, Bettina Matzdorf, Thomas Aenis." Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1203623909/34.

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Dissertations / Theses on the topic 'Energy Ecosystems'

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