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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.
71

EFFECTS OF TIME, SEED SOURCE, AND PLANT COMPOSITION ON MACROINVERTEBRATES IN RESTORED PRAIRIE

Wodika, Ben 01 August 2015 (has links)
Invertebrates influence primary productivity and nutrient cycling in ecosystems. They are also important links between producer and higher trophic levels. Despite their important role in terrestrial ecosystem function, invertebrates are frequently overlooked in ecological restorations. Thus, the objective of this research was to quantify how belowground macroinvertebrate ecosystem engineers and communities change over time following ecological restoration and examine whether the source of dominant plant species and the composition of non-dominant plant species influence aboveground macroinvertebrates community structure in restored prairie. A chronosequence design (space for time substitution) was used to determine the role of restoration age, plant community, and soil structure on the recovery of two belowground macroinvertebrate ecosystem engineers (Chapter 2). Ants and earthworms were sampled from cultivated fields, grasslands restored for 1-21 years, and native prairie. Earthworm abundance increased with time since cessation of cultivation, concomitant with prairie establishment. The abundance and biomass of ants were more related to the structure of restored plant communities than time since restoration. The dominance of exotic earthworms, and a generalist ant species in these restorations, coupled with their known capacity to alter soil properties and processes, may represent novel conditions for grassland development. The same chronosequence of agricultural fields, restored prairies, and prairies that were never cultivated was used to address the second objective of this research, which was to quantify how the belowground macroinvertebrate community composition changed in response to ecological restoration and whether the communities became representative of undisturbed (“target”) communities. Macroinvertebrate communities in the two remnant prairie sampled were distinct from restorations and continuouslycultivated fields. The macroinvertebrate communities in prairie that had never been cultivated were also distince from each other, indicating a “target” community is hard to define. Belowground macroinvertebrates changed in a trajectory that was not representative of either remnant prairie, but was representative of the an average of both remnant prairies. Thus, if you reconstruct prairie from cultivated soil conditions (“build it”), macroinvertebrates will colonize (“come”), but attaining a community representative of a specific target may require introduction from that target. Colonization of macroinvertebrates in restorations aboveground are most likely to be influenced by aspects of the plant community. A third objective of this research was to quantify whether variation in dominant species (cultivars vs. local ecotypes) and composition of subordinate species (local species pools) influence the composition of aboveground macroinvertebrates. Macronvertebrate abundance, richness, diversity, trophic groups and community composition in late summer did not vary between prairie restored with cultivar and local ecotypes of the dominant grasses. This was observed in two field experiments. The species pool treatment did influence the macroinvertebrate community, as one species pool had slightly higher morphospecies diversity and hymenopterans that the other two species pools. This was likely due to the presence of an ant-tended legume, Chamaecrista facsciculata Michx., in one species pool. Overall, this research demonstrates that time since the cessation of disturbance (cultivatation) and plant communities influence macroinvertebrate communities in restored prairie. Restored prairies in the Midwest are likely to be colonized by exotic earthworms and cosmopolitan ants. More research is needed to reveal how they influence ecosystem functioning.Belowground, macroinvertebrate communities may not represent restoration “targets” and these “targets” may be hard to define if remnants are rare or there is a high degree of spatial variation on the landscape. Variation in plant communities above ground appears to influence the structure of aboveground macroinvertebrate communities more than variation within dominant species. Whether this aboveground variation is reflected is reflected belowground deserves further investigation.
72

Evolving to a new service-dominant logic for health care

Joiner, Keith, Lusch, Robert 01 1900 (has links)
Consumers value health and a sense of well-being. The health care system cannot supply these values, but only "products" such as hospitalization, ambulatory care, medications, procedures, and preventative care. These components of health care represent neither the value within the system nor the desired final output. Nonetheless, the health care system has focused inordinately on the products, to the point of suggesting that they have intrinsic value. We link this situation to the concept of goods-dominant logic, which has dominated business and managerial thinking since the Industrial Revolution. We then explain why and how moving to service-dominant logic is essential for consumers and providers to better cocreate value from products which are not intrinsically valuable. The challenge of cocreating value is confounded by information asymmetry, and by the myriad factors in the health care ecosystem that contribute to or detract from health and well-being. A new lexicon, emanating from service-dominant logic, is suggested to facilitate the move away from a goods-dominant mindset.
73

Valuing the natural resources and ecosystem services of Leliefontein communal rangeland in Namaqualand, South Africa.

Ogidan, Oluwagbenga Olaitan January 2014 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / Natural resources play important roles in ecosystem service delivery, more especially in rural households where livelihoods depend heavily on natural resources for the delivery of ecosystem services. The various benefits derived from provisioning, supporting, regulating and cultural services of natural ecosystems such as food, medicines, carbon sequestration, spiritual fulfilment all support human life and sustain its well-being. Research on valuation of natural resources suggest that the values derived mainly from non-marketed natural resources are insignificant and thus, not reflected in national accounts. Economic valuations have traditionally been concerned with the quantification of direct use values of ecosystem services that are marketed to produce tangible benefits. The scope of natural resource valuations have, however been broadened by scientists in recent years to consider passive or non-use values to reflect the total economic values of natural resources and ecosystem services to societies. In this study, I valued the streams of ecosystem services derived from natural resources in Leliefontein communal rangeland; an area of 192 000 hectares in the semi-arid region of Namaqualand in South Africa. Rangeland forage for livestock, medicinal plants, fuelwood, and water resources from the Communal Area were valuated for one production year between January and December 2012. Valuation was done to incorporate both marketed and non-marketed natural resources which were used within the production year. The total economic value for the area was estimated at R20 156 672 per annum. Value of rangeland forage was estimated at R61.92 ha-1 yr-1, fuelwood’s value was estimated at R25.04 ha-1 yr-1, value of medicinal plants was R2.26 ha-1 yr-1 and water resources valued at R9.45 ha-1 yr-1. The non-use value was estimated by eliciting the willingness to pay for the conservation of the natural resources using a contingent valuation method. Economic value of natural resources in Leliefontein increased to R105 per hectare from R99 when non-use value was added to reflect the total economic value of ecosystem services in the area. Household income level positively correlated with individual’s willingness to pay for ecosystem services. I recommend that decision making should take into account the socio-economic conditions of a community when determining the total economic value of ecosystem services. Non-use value of the ecosystems should be considered especially in rural areas where people depend on the natural environment for livelihoods and socio-cultural well-being. Sustainable and equitable utilisation of natural resources for the purpose of maintaining a sustainable flow of critical ecosystem services should form the basis for formulating policies on land use and sustainable development.
74

Investigating Realistic Scenarios of Biodiversity Loss on Ecosystem Functioning: Extirpation of Rare Species and Food Web Collapse in Tropical Floodplain Lagoons

Pendleton, Richard McCall 05 1900 (has links)
This thesis investigates the influence of nonrandom species loss on the structure and functioning of trophic floodplain lagoons. Two experiments were conducted based on different realistic scenarios of biodiversity loss using multitrophic fish assemblages derived from long-term survey data. Loss of fish diversity influenced overall ecosystem multifunctionality of these lagoons through complex multitrophic interactions throughout the aquatic food web. These results indicate that biodiversity loss from diverse multitrophic ecosystems can influence ecosystem structure and function and likely deviate from simplified food chain dynamics or patterns that emerged from single trophic level studies.
75

From Collaboration to Knowledge: Planning for Remedial Action in the Great LAkes

Keuhl, David 11 December 2001 (has links)
The goal of planning is to use knowledge to determine action. Planning theory has focused specifically on how the process of achieving this occurs. Two dominant theories prevail: rational comprehensive and communicative planning theory. The former relies heavily on the scientific method as a model for acquiring knowledge from which the correct action can be determined. The latter suggests that collaborative processes that engage stakeholders in decision-making offer distinct advantages to achieving both knowledge and action through consensus processes. This study looks at how knowledge is developed in collaborative planning processes used in ecosystem management. Knowledge is defined as more than simply data and information. It includes the tacit elements that underlie and give meaning to the data and information. As such, it requires processes that are more communicative in nature. At the same time, ecosystem management practices are rooted in the natural sciences and rely heavily on rational, instrumental reasoning to determine management plans. This combination of rational and communicative approaches provides for an interesting setting in which to understand the interaction of the two and to determine if there are advantages to conceptualizing planning in one way or the other. The study targets the remedial action planning done in the Great Lakes since 1987. Forty-three Areas of Concern were established throughout the basin, and in each, a stakeholder planning committee established. The committee was charged with developing a plan for remediating the water quality of the area. Over the past fourteen years, they have struggled through many circumstances to accomplish this with varying degrees of success. As each utilized slightly different procedural approaches and faced different obstacles, they provide an excellent laboratory for comparison. The study offers an analysis of the elements of the process and the implications of the different ways of approaching the various steps and stages. The analysis focuses on revealing what needs to be intact prior to collaborating, how information is collected, shared, and utilized, and how decisions are made and formalized in these processes. It focuses specifically on the information itself, communication issues, structural elements, and factors outside the process and how these all work together to enhance or inhibit collaboration. Following a detailed analysis of the process, a model for doing ecosystem management based on knowledge is developed and the basic principles of the model suggested. Collaboration is often theorized to accomplish far more than simply improved knowledge for decision-making. Some believe it will improve democracy, equality, and accountability. The study concludes with a brief reflection on these possibilities. / Ph. D.
76

Amazon Forest Response to Changes in Rainfall Regime: Results from an Individual-Based Dynamic Vegetation Model

Longo, Marcos 25 February 2014 (has links)
The Amazon is the largest tropical rainforest in the world, and thus plays a major role on global water, energy, and carbon cycles. However, it is still unknown how the Amazon forest will respond to the ongoing changes in climate, especially droughts, which are expected to become more frequent. To help answering this question, in this thesis I developed and improved the representation of biophysical processes and photosynthesis in the Ecosystem Demography model (ED-2.2), an individual-based land ecosystem model. I also evaluated the model biophysics against multiple data sets for multiple forest and savannah sites in tropical South America. Results of this comparison showed that ED-2.2 is able to represent the radiation and water cycles, but exaggerates heterotrophic respiration seasonality. Also, the model generally predicted correct distribution of biomass across different areas, although it overestimated biomass in subtropical savannahs. / Earth and Planetary Sciences
77

Ekosystemtjänsternas årstidsvariation och potentiella säsongsutveckling – en del av Swecos vit-, grön- och blåstrukturplan för Gällivare kommun

Ekelund, My January 2015 (has links)
The term Ecosystem Services describes all the direct and indirect contributions ecosystems have on human welfare. Fresh water, clean air, genetic diversity, recreation and inspiration are some examples of ecosystem services we get from nature but often take for granted. The human way of living affects our ecosystem and by transforming natural surfaces to unnatural surfaces important ecosystem and their services might be lost or hard to reconstruct. There is a growing support from the community that the value of ecosystem services should be integrated into decision-making in our society.   Gällivare municipality plans for a big infrastructure investment. By knowing which ecosystem services that are important for people living in the city of Gällivare, the municipality can take the ecosystem services into consideration and optimize and reach multifunctionality in natural surfaces providing important ecosystem services. As a part of Gällivare municipality’s work to integrate ecosystem services in their infrastructure investment, this thesis studies ecosystem services during different seasons in the city of Gällivare. This master thesis examines ecosystem services in four different places in Gällivare. An assessment of important ecosystem services in every place was done based on information during a workshop with Gällivare municipality. Eleven or twelve ecosystem services in every place were considered especially important for the municipality. The prioritized ecosystem services were the cultural and the regulating services. How people in the locality experience the cultural services, recreation, mental & physical health; aesthetic appreciation, inspiration & education; tourism and spiritual experience & "sense of place" and what they think of the services' potential development in the future were further studied with a questionnaire and interviews. The regulating ecosystem service local climate regulation was further studied by calculations of the ability of vegetation and water to affect the local temperature. The ability of ecosystems to clean storm water and regulate water flows was studied by inspecting flood maps for the city of Gällivare and standard levels of pollutions in storm water from different land uses.  Early in the study it was found that, during the winter season, existing ecosystem services are mostly cultural services since the ecosystem is in rest during winter and thereby can't deliver the same diversity of services as in summer. During summer season, results showed that vegetation could affect local climate by stabilizing the temperature. The vegetation also delays water flows, which is important during spring when there is a large amount of melt water and during heavy raining. The amount of pollutions in surface water is also reduced by vegetation.
78

An ecosystem service perspective of the ecological restoration measures to mitigate small-scale hydropower impact in river Billstaån : Steps towards monitoring and dissemination of ecosystem services

Tellström, Susanne January 2017 (has links)
Ecosystem services, capturing the benefits and values of functioning ecosystems for human well-being, is a concept receiving increasing attention both in science and policy. This study investigates the utility of considering ecosystem service in the ecological restoration of a river affected by small-scale hydropower. While hydropower is a renewable energy source, it has impacts on the ecological status in water sheds and generates issues addressed e.g. by the EU Water Directive. To mitigate ecological impacts, and maintain hydroelectricity production that better correspond to the Water Directive, several restoration measures are carried out in river Billstaån, County of Jämtland, Sweden.   This study presents an ecosystem service perspective of the restoration process in river Billstaån linked to recommendations in terms of further interpretation, monitoring and communication of the assessment results. By applying evaluation of ecosystem services to the case of river Billstaån, it is examined to what extent ecosystem service descriptions can give support in monitoring and communication of the results of the ecological restoration efforts.   Ecosystem services were assessed for the restoration outcomes in river Billstaån using the two frameworks Corporate Ecosystem Service Review (ESR) and Toolkit for Ecosystem Service Assessment (TESSA), respectively. The ecosystem services deemed most important partly differed between the two frameworks due to different assessment perspectives. However, both ESR and TESSA pointed out ecosystem services connected to recreation and tourism as important, indicating a potential regarding recreational use of the area. Such socio-economic impacts of the restoration project was not included in the planning of the restoration, but if identified and utilized such “added benefits” might give opportunities for local rural development beyond the restoration work itself.   Contrasting the results from the ecosystem service assessment of river Billstaån towards the Swedish Environmental Objectives identified two direct and seven indirect connections. Through these connections the restoration project can be presented in relation to national goals. Indicating such connections can help in communicating the ecosystem service perspective. For future monitoring of project outcomes in river Billstaån, a set of potential indicators were identified using an ecosystem service approach, that can complement the planned monitoring of ecosystem functions. For future monitoring of ecosystem service development it is advisable to use a combination of indicators that reflect both the ecosystem function availability and the ecosystem service use. Three types of illustrations that can support different perspectives in future communication regarding ecosystem services in river Billstaån were identified in this study and termed system, overview and single service perspective. Example illustrations include a Causal Loop Diagram, a hot-spot map and a range of photos, respectively. The illustrations are deemed to present the assessment results in a more accessible way and can be adapted to a diversity of future communication settings. / <p>Betyg 2017-06-14</p>
79

Ekosystemtjänster i stadsplanering / Ecosystem services in urban planning

Engelin Edvinsson, Tobias January 2016 (has links)
Ekosystemtjänster är ett relativt nytt begrepp inom fysisk planering och kan beskrivas som de olika gratistjänster människan får från jordens olika ekosystem. Utan dessa gratistjänster skulle jorden inte vara en beboelig plats för människan. Därför är tjänsterna vi får från naturen livsavgörande för vår och andra arters existens. Men trots att ekosystemtjänster är av oerhört värde för mänskligheten och dess socioekonomiska samhälle saknas det idag kunskap om detta område - inte minst inom fysisk planering. Dessa tjänster saknar, vad man kallar, ett marknadsvärde vilket har lett till att det är svårt att uppskatta det ”riktiga värdet” av de tjänster vi får från naturen. Hur sätter man ett värde på exempelvis fördelarna med pollinering, stadsodlingar, de psykiska och fysiska fördelarna med urbana grönytor samt den naturliga vatten- och luftrening som ständigt sker? Det är ingen lätt fråga att besvara. Okunskap om ekosystemens olika tjänster kan få förödande konsekvenser i en allt mer globaliserad värld med ekonomier som ständigt växer. Där majoriteten av världens befolkning bor i städer som växer både på bredden och på höjden samtidigt som jorden står inför globala klimatförändringar med varmare klimat, kraftigare nederbörd et cetera. Ekosystemtjänster har visat sig användbara i många av dessa fall, om de används på rätt sätt. Ekosystemtjänster renar exempelvis vår luft i täta städer, de reglerar temperaturer i städer, de kyler byggnader under heta sommardagar, de har ett rekreativt värde för människor och har även visat sig effektiva för att motverka stress och andra psykiska sjukdomar. Fördelarna är många och kunskap om hur de kan användas på bästa sätt kan ge stora samhällsvinster. Fysisk planering är ett av de främsta medlen för att kunna hantera och nyttja ekosystemtjänsterna på lämpligast sätt. Men trots detta saknas det idag kunskap bland planerare inom detta område. Med min uppsats hoppas jag därför kunna bidra till att väcka fler planerares, arkitekters, politikers och andra aktörers intresse för att förstå värdet av att använda ekosystemtjänster inom stadsplanering. / Ecosystem services are a quite new notion within urban planning and it can be described as those services the human get for free from the Earth´s different ecosystems. Without these free services the Earth would have been uninhabitable. Thereof the services we get from the nature are vital for our own and for other species existence. However, despite the great value and impact ecosystem services have to humanity and our socioeconomic society there is lack of knowledge within this field  and urban planning is not an exception. Ecosystem services do not have any market value and this has lead to difficulties to understand the ”real value” of the services we get from the nature. For instance, how do we value pollination, the benefits of urban farming, the physical and mental benefits of urban green areas or the value of natural purification of water and air et cetera? It is not an easy question to answer. Lack of people´s knowledge regarding the benefits of ecosystem services can have devastating consequences. Especially in a globalised world where the majority of the people in the world live in cities and at the same time when the Earth is facing global warming. However, ecosystem services have proved to be very efficient if they are used the right way. For example, ecosystem services purify the air from impurities and regulate the temperature in our cities, cooling down buildings during hot summer days, they also have a recreational value and have proved to cure stress and other diseases. The benefits are many and if we possess the knowledge of these services and are able to control them in the very best way it can give back social benefits. Urban planning is one of the main means to manage and use the ecosystem services in the best way. Despite this, many urban planners don´t have enough with knowledge within this field. My wish with this dissertation is to contribute and share my knowledge to other planners, architects, politicians and other operators who work with urban planning in a daily basis. I want to grow a seed of interest and write about the importance of why we shoud be using ecosystem services within urban planning.
80

Risk management in a business ecosystem

Bergström, Alexander, Karlson, Anton January 2019 (has links)
Purpose - The purpose of this thesis is to advance the understanding of risk exposure and management for different roles in business ecosystems. The following research questions have been derived to fulfill this purpose: RQ1: Which risks are different business ecosystem roles exposed to, and in what way? RQ2: How can business ecosystem actors mitigate risks? Method – A single case study has been conducted on a business ecosystem surrounding the development of autonomous cars in the EU. An abductive and qualitative approach has been applied, which allowed the combination of existing literature and new empirical findings as to the foundation for building new theory. Data was collected through 21 semi-structured interviews and analyzed through comparison between codes on risks, roles, and risk mitigation strategies. Findings – The already existing literature on business ecosystem risks was confirmed and nuanced. On top of this, two new risks were found, disintermediation risk (the risk of being fully or partially excluded from the ecosystem) and accountability risk (the risk of being responsible for other business ecosystem actors output to a third party). The findings also declare that risks vary between actors, but also due to other factors such as investment in the ecosystem and an actor's relative size to other actors. Finally, suggested risk response strategies for each risk were derived. Theoretical implications - We have contributed to the literature on risks within business ecosystems by adding two new risks: disintermediation risk and accountability risk. We have also contributed to the overall literature on business ecosystems by combining the two sub-streams risks in business ecosystems and roles in business ecosystems. In addition to the theoretical implications for the business ecosystem literature, we have contributed to the risk management literature by applying it in the new context of business ecosystemsto extend the applicability of the risk management literature. Practical implications - Our findings shed light on how risks are distributed between different roles and can therefore provide guidance in this issue. The current study also contributes to the understanding of how risks vary with respect to other factors than roles, which could be valuable knowledge for managers. Finally, practical guidance on how risks can be mitigated is presented which is valuable for any actor in a Business ecosystem.

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