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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

In the search of the student's role in innovation ecosystems

Alenbring, Cornelia January 2023 (has links)
Abstract  Level: Master thesis in Innovation and design , 30 credits Institution: School of Innovation, Design and Technology, Mälardalen University Author: Cornelia Alenbring (98/05/24)   Title: In the search of the student's role in innovation ecosystems Supervisors: Anders Vikström, Erik Bjurström MDU examinator:Yvonne Eriksson Keywords: “ecosystems for innovation”, “eco systems for social innovation”, “social innovation ecosystems”, “quadruple helix” “students- innovation ecosystem” “students role in innovation ecosystems” Purpose: The purpose of this study is to explore the specific role of students in innovation ecosystems. By gaining a deeper understanding of their role, this research aims to contribute to a more nuanced micro-dynamic perspective on the role of students in innovation ecosystems. This thesis explores conceptualizations and metaphors of innovation ecosystems with the aim of exploring different theorizing in the field, related to the role of students within those.  Research question: What is the role of students in innovation ecosystems? Method: The study was based on a qualitative method. The empirical data was collected through semi-structured interviews and observations using focus groups with 5 actors within the public, academia, industry and civil society. Conclusion: The role of the student is at the heart of the innovation ecosystem metaphor - that of emergence and co-evolution. Rather, the empirical evidence of this thesis concurs that the roles available to students also depend on other actors taking them seriously, and that the reasons for less than optimal exchange between students and other actors deserves further investigation.  It is an interesting observation that students fall between the system perspective’s grand theorizing and pedagogics’ narrower focus on education: - So what is the point of pursuing a research approach where either students or ecosystems are not mentioned? There is an obvious gap in where the abstract level of the system perspective, whilst it can serve as an overview of the concept,  does not specify actors and misses to provide a micro perspective on what is occurring between actors, that could explain how it all happens. Are students rather representatives of the civil society, or of what Powell referred to ‘amphibians’, or representative of nothing but themselves as individuals-in-the-making, as a representative of becoming itself and emergence in itself – through their interaction on a campus which they don’t own, but inhabit? And what do companies really want when they want to be a campus? What is special about a campus and life on a campus? What is the very essence of it?
182

Optimizing Carbon to Nitrogen Ratios to Improve Nitrogen Removal in Agricultural Drainage Ditches

Faust, Derek Ronald 07 May 2016 (has links)
Since 1961, a fourold increase in application of fertilizers in the United States has helped to double crop yields. Nutrients not used by crops are often transported to aquatic ecosystems adjacent to agricultural fields. In the Lower Mississippi Alluvial Valley, nutrients enter agricultural drainage ditches and are transported to receiving water bodies, eventually reaching the Gulf of Mexico. The annual occurrence of a hypoxic zone in the Gulf of Mexico is caused by nitrogen loads from the Mississippi River Basin. Objectives of these studies were: (1) evaluate how organic carbon amendments affect nitrate-nitrogen removal in agricultural drainage ditch systems, (2) determine effects of organic carbon amendments and flow rate on nitrate-nitrogen removal in a semi-controlled field setting using experimental drainage ditches, and (3) assess relationships between organic carbon and nitrogen content of overlying water, pore water, and sediments of drainage ditches throughout the Lower Mississippi Alluvial Valley. In laboratory experiments, nitrate-nitrogen removal in dissolved and particulate organic carbon treatments was greater than 90% compared to as low as 60% in control treatments. The optimal carbon-to-nitrogen ratio of organic carbon amendments for efficient nitrate-nitrogen removal was 5:1. Studies in experimental drainage ditches revealed that flow substantially lowered the ability of organic carbon amendments to remove nitrate-nitrogen with a maximum percent nitrate-nitrogen reduction of 31.6% in a dissolved organic carbon treatment, although implementation of low-grade weirs in experimental drainage ditches did result in removal of nitrate nitrogen in all treatments and at all flow rates. Examining the nitrogen and organic carbon contents in agricultural drainage ditches throughout the Lower Mississippi Alluvial Valley revealed that organic carbon content in overlying water, pore water, and sediments is lower than observed in other wetland-like ecosystems and indeed may be limiting denitrification and other nitrogen removal processes. Increasing organic carbon content overall could be achieved by using organic carbon amendments, but this body of research highlights that additional studies are necessary to ensure successful implementation of organic carbon amendments that reach their greatest potential as a management practice to effectively remove nitrate-nitrogen in the realistic settings of agricultural drainage ditches.
183

Exploration of the current state of the entrepreneurial ecosystem that supports the transition to a circular economy in Sweden

Bedin, Stephanie, Janevska, Sanja January 2022 (has links)
To tackle the current global climate and sustainability challenges, Sweden aims to transition to a circular economy and society. The purpose of this thesisis to explore and gain a better understanding of the current state of theentrepreneurial ecosystem on a national level that supports the transition to acircular economy in Sweden and explore potential collaborative activity between the components of the entrepreneurial ecosystem. This thesis favours a qualitative approach and an inductive strategy, thus forty semi-structured interviews were conducted with components of the entrepreneurial ecosystem.The theoretical framework consists of a conceptual framework based on the two concepts entrepreneurial ecosystem (phenomena) and circular economy (context) which provide a springboard for the thesis. The findings outline that there is no consensus amongst the interviewees concerning the existence of the entrepreneurial ecosystem that supports the transition to a circular economy in Sweden. Thus, the entrepreneurial ecosystem that supports the transition to acircular economy in Sweden is still in the starting phase and needs to overcome several challenges in order to be able to provide a favourable and supportive entrepreneurial climate to transition to a circular economy in Sweden. This thesis makes a valuable academic contribution to the scarce literature on the topic and has practical relevance by providing a unique overview and understanding of the current state of the entrepreneurial ecosystem supporting the transition to a circular economy in Sweden and the collaborative activity within, which can be further useful to already existing and new components within the entrepreneurial ecosystem, as well as further useful for researchers.
184

Controls over stream temperature in a northern boreal landscape

Damström, Oskar January 2023 (has links)
With widespread increases in air temperature, it is expected that the temperature of aquatic ecosystems will also increase, especially at high latitudes. Warmer streams and rivers could have severe, direct impacts on cold-adapted aquatic fauna but may also indirectly influence species by reducing the amount of suitable habitat. Yet, increases in air temperature alone ara potentially insufficient to cause stream warming, which is also influenced by a range of other factors that govern the energy balance of individual stream reaches. Here, I used long-term water temperature data from seven streams in the Krycklan Catchment Study (KCS) to ask whether there are recent trends in warming, and to evaluate how catchment properties regulate the sensitivity of streams to air temperature change during summer. Mann Kendall trend analysis at one headwater site showed that there has indeed been a warming trend in the KCS, but only during a brief time-window in early summer. Across, KCS sites, air temperature-water temperature regressions highlighted notable variation in the thermal sensitivity of streams depending on their catchment features. Finally, observations during extreme warm and dry years did not indicate strong responses in terms of stream temperature. In fact, extreme low-flow conditions seem to reduce the downstream propagation of warm lake water during these events. Collectively, my results suggest that ongoing climate changes in the boreal region have not had dramatic influences on stream temperature, although future changes occurring around the snowmelt season are likely.
185

How introduced earthworms alter ecosystems

Eisenhauer, Nico 31 January 2024 (has links)
We all know earthworms as important friends in our garden: they help plants to grow better by providing nutrients, water, and air in the soil. However, in some cases, earthworms have more negative effects. This is because other organisms need to be used to the activities of earthworms to benefit from their presence. Some regions of the world have developed without earthworms for over thousands of years. For example, in northern North America, earthworms have been absent for more than 10,000 years and have only been re-introduced over the past 400 years. In many cases, introduced earthworms find a perfect environment, because no other organisms have been able to use the resources that these earthworms now consume. As so-called ecosystem engineers, earthworms dramatically alter many ecosystem characteristics. In this article, we summarize the known consequences of earthworm invasion, report on how scientists study these, and highlight remaining knowledge gaps that you might help solving should you decide to become an ecologist.
186

Cicada Carcass Subsidies and Warming Temperatures Accelerate Larval Amphibian Development

Gallagher, Elizabeth N. 26 July 2022 (has links)
No description available.
187

Public Ecology: Linking People, Science, and the Environment

Robertson, David P. 12 June 2002 (has links)
Truly unique and innovative solutions are needed to resolve today's complex and controversial environmental issues (e.g., biodiversity loss, global warming, cultural evolution, etc.). In response to these concerns, a variety of applied science programs have emerged to help people make better decisions about the environment. Each of these programs (e.g., conservation biology, restoration ecology, sustainable forestry, environmental toxicology, and others) produces specialized knowledge that is used to achieve specific social and environmental goals. For example, the peer-reviewed, scientific analyses published in Conservation Biology are most likely concerned with the goal of preserving biological diversity, whereas the equally scientific and respected analyses published in Forest Science are most likely concerned with the goal of sustaining timber yields. Likewise, studies in environmental toxicology investigate risks to human health by environmental pollutants, while stud! ies in ecological restoration serve to maximize the integrity of natural systems. Unfortunately, these diverse forms of knowledge offer multiple and often conflicting ways of thinking about the environment. Public ecology is a response to this dilemma. The primary goal of public ecology is construct common ground between people's diverse beliefs and values for the environment. Toward this end, public ecology is an interdisciplinary and collaborative approach to environmental science and politics. Public ecology integrates perspectives from the social and natural sciences, the humanities, and public understandings of the environment. Public ecology is not only a cross-cultural and comparative form of environmental studies, it is also a citizen science that encourages all concerned stakeholders to participate with research specialists, technical experts, and professional decision-makers in developing creative solutions to persistent environmental problems. / Ph. D.
188

Modelling hydrologic system change in a paraglacial catchment in the Northern Rocky Mountains

Kern, Jennifer M. 10 June 2021 (has links)
The Northern Rocky Mountains, home to the highest concentration of glaciers in the American West, are undergoing increased rates of climate warming, resulting in previously unseen ecological and hydrological outcomes. Globally, many glacier basins have experienced glacial recession to the threshold point of surpassing peak basin runoff, resulting in substantial decreases in local hydrological yield. Such findings call for models that do not alone examine glacial runoff but a complete examination of changes in the water budget. Alpine catchments are increasingly vulnerable to evapotranspirative losses due to climatic warming, and the rates of vegetation succession are often unable to keep up with the rate of warming. Basin scale analyses of glacial recession on streamflow are then confounded by ecohydrologic dynamics created by primary succession and the associated increase in evapotranspiration. In this study, I present a conceptual framework for modelling basin runoff in landscapes responding to paraglacial adjustment. The study goal was achieved by calibrating and running the Hydrologiska Byråns Vattenbalansavdelning (HBV) model in Swiftcurrent basin and investigating change across the basin water balance through baseflow analysis. The research findings indicate catchment scale changes in the timing and magnitude of the flow regime in the deglaciating Swiftcurrent basin, by employing HBV and empirical baseflow analysis. While most components of the water balance appear consistent across the study period, late summer baseflow values suggest the basin hydrology is undergoing changes, possibly a result of melt occurring earlier in the season. Ultimately, I advocate for an adaptable and accessible approach to understanding paraglacial basins by constructing an estimation of basin-scale water budgets. / Master of Science / Large scale trends in climate change are impacting a variety of ecosystems, especially alpine environments. Glacial recession has been well documented and studied in mountain chains across the globe, including the Rocky Mountains. Recession of these massive bodies of ice, which can be viewed as reservoirs of water in droughts or low flow months, has severe implications for society, the economy, and sensitive mountain environments. Furthermore, the new terrain exposed from beneath the melting glacier is dynamic and will undergo many adjustments geomorphically, in soil development, and ecologically as plants move up the glacier foreland. Ecological systems experiencing warming, deglaciation, and vegetation succession are not well understood and are complex environments due to the multiple inputs, interactions, and feedbacks. As such, this research examines how hydrologic conditions across a forty year period are changing in response to the complex feedbacks between glaciers, newly exposed terrain, and associated runoff. Through modeling and analysis, this study offers a method for understanding the water balance of Swiftcurrent basin in Glacier National Park, which can be used in other catchments experiencing similar changes.
189

Cultivating Curriculum: How Investing in School Grounds, the Streetscape and Vacant Land as Urban Ecosystems can Address Food Security, the Community and Institutions of Public Education

McAllister, Karen Elizabeth 23 September 2019 (has links)
The 2014 Agricultural Act (Economic Research Division) (aka: The Farm Bill) was an important limelight shone on the issue of access to healthy foods, food education and the correlation between an increasingly unhealthy population and proximity to fresh, healthy food. Further legislation such as the Urban Agricultural Production Act of 2017 has been introduced to leverage the Farm Bill's financial incentives to promote urban agricultural programs and transform vacant land into agricultural use. Specifically, this has become increasingly common in many lower income and disadvantaged communities affected by a lack of access to fresh food stores. Additionally, in response many public schools have pro-actively sought funds to transform their schoolyards into gardens and teaching classrooms (Gamson) in order to provide food literacy and education however, this practice remains the exception. Many children still face a lack of healthy food options or the availability of any fresh food outside of their school environment. What if the standard education facility could be used as a tool to confront not only the architecture of the learning space, but a school-as-ecosystem, representing a neighborhood catalyst to teach through action – addressing comprehensive global issues brought on by food desert environments and a child's perspective about their own health? This thesis explores the possibility of casting the urban ecological net wide- envisioning a timescale for transforming public spaces and school grounds using green infrastructure practices, biological remediation, planning for changes in transportation technology and the expectations of a public education and child's perception about their environment. Emphasizing a broad focus on all of the potential sites for food production in the city (including the school, schoolyard and what they represent to the community), surfaces a multi-functioning methodology encompassing community identity, amenity, ecology, infrastructure and beauty envisions what could become of urban areas in the future. The primary goal is to educate future generations in the value of the food network and to give them the kind of direct hands-on experience that educators emphasize while concurrently nourishing urban communities through development of a project carried out in common, one that has health benefits for the population, that engenders a sense of long-term pride, and that empowers people to make change in their environment, even in modest or temporary ways. The idea that school design can encourage and facilitate, hinder and inhibit behaviors at school, and the architectural symbolism of schools can have a profoundly wider impact on children and their behaviors in and outside of school (Tucker). There is a significant psychological difference in learning about the environment, for the environment and in the environment (Malone). Creating public space focused on individual learning and the physical and mental health of the individual aims to balance the scales of social economic injustices. It is going to take every effort from the hyper-localized to city-wide and even regional scales to make significant urban changes to create a taxonomy of spaces to support the growth of our cities while simultaneously educating young minds on the value of understanding our ecological relationship to the city and surrounding environment. / Master of Science / The 2014 Agricultural Act (Economic Research Division) (aka: The Farm Bill) was an important limelight shone on the issue of access to healthy foods, food education and the correlation between an increasingly unhealthy population and proximity to fresh, healthy food. Further legislation such as the Urban Agricultural Production Act of 2017 has been introduced to leverage the Farm Bill’s financial incentives to promote urban agricultural programs and transform vacant land into agricultural use. Specifically, this has become increasingly common in many lower income and disadvantaged communities affected by a lack of access to fresh food stores. Additionally, in response many public schools have pro-actively sought funds to transform their schoolyards into gardens and teaching classrooms (Gamson) in order to provide food literacy and education however, this practice remains the exception. Many children still face a lack of healthy food options or the availability of any fresh food outside of their school environment. What if the standard education facility could be used as a tool to confront not only the architecture of the learning space, but a school-as-ecosystem, representing a neighborhood catalyst to teach through action – addressing comprehensive global issues brought on by food desert environments and a child’s perspective about their own health? This thesis explores the possibility of casting the urban ecological net wide- envisioning a timescale for transforming public spaces and school grounds using green infrastructure practices, biological remediation, planning for changes in transportation technology and the expectations of a public education and child’s perception about their environment. Emphasizing a broad focus on all of the potential sites for food production in the city (including the school, schoolyard and what they represent to the community), surfaces a multi-functioning methodology encompassing community identity, amenity, ecology, infrastructure and beauty envisions what could become of urban areas in the future. The primary goal is to educate future generations in the value of the food network and to give them the kind of direct hands-on experience that educators emphasize while concurrently nourishing urban communities through development of a project carried out in common, one that has health benefits for the population, that engenders a sense of long-term pride, and that empowers people to make change in their environment, even in modest or temporary ways. The idea that school design can encourage and facilitate, hinder and inhibit behaviors at school, and the architectural symbolism of schools can have a profoundly wider impact on children and their behaviors in and outside of school (Tucker). There is a significant psychological difference in learning about the environment, for the environment and in the environment (Malone). Creating public space focused on individual learning and the physical and mental health of the individual aims to balance the scales of social economic injustices. It is going to take every effort from the hyper-localized to city-wide and even regional scales to make significant urban changes to create a taxonomy of spaces to support the growth of our cities while simultaneously educating young minds on the value of understanding our ecological relationship to the city and surrounding environment.
190

Shade, Moisture, and Woody Vegetation in Stormwater Management Basins: Influence on Cattail (Typha spp.) Growth

Bocskor, Priscilla 13 May 2010 (has links)
Stormwater management basins (SWMB) are used to mitigate urban runoff. The Virginia Department of Transportation relies on dry detention basins planted with mowed turfgrass. However, these basins often retain water; resulting in cattail (Typha spp.) and tree colonization. Managing agencies request cattail eradication and trees are also removed. However, if trees were allowed to remain they could alter basin dynamics, making conditions unsuitable for cattails. In a greenhouse study we tested the impact of three shade (heavy, medium, full sun) and soil moisture (dry, moist, flooded) treatments on cattail growth. After two months, cattail biomass indicated a strong interaction between soil moisture and shade (p<.0001). Increases in shade and reductions in soil moisture resulted in decreased biomass and rhizome length. Heavy shade and dry soil produced the most reductions in cattail growth (95% less biomass, 83% smaller rhizomes than cattails in full sun and flooded soil). However, considerable growth reductions still occurred in medium shade and moist soil (66% for biomass and 74% for rhizome lengths). In a field study in four unmaintained SWMB in Virginia, environmental data (litter layer, water table, soil organic matter, etc.) and vegetation composition (cattail and other herbaceous biomass, and woody vegetation influence index) were collected from 100, 0.25-m2 plots. Principal component analysis indicated cattails and trees occupy opposing environmental spaces. Water table is most strongly correlated to cattail biomass. While these results suggest trees could eliminate cattails from SWMB, more research is needed to determine the long-term impacts of trees on basin function. / Master of Science

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