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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.
1

Influences of some exogenous factors on the gastrointestinal ecosystem /

Gustafsson, Aina, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
2

A post-classical economics approach to ecosystem management : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University, Te Whare Wānaka o Aoraki /

Hearnshaw, Edward J. S. January 2009 (has links)
Thesis (Ph. D.) -- Lincoln University, 2009. / Includes case study of Te Waihora/Lake Ellesmere. Also available via the World Wide Web.
3

A review of the social component of ecosystem assessments with recommendations for Oregon /

Armstrong, Catriona M. M. January 2000 (has links)
Thesis (M.S.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 133-145). Also available on the World Wide Web.
4

A Landscape Approach to Ecosystem Services in Oregon's Southern Willamette Valley Agricultural Landscape

Enright, Christianne 11 July 2013 (has links)
Over the past decade, ecosystem services has become a familiar term. Definitions vary but the central idea is that society depends on and is enhanced by earth's resources. Concerns about natural resource depletion and degradation have motivated researchers to move from concept to operation and real-world change. Since the late 1990s, attention has been directed at characterizing the monetary value of ecosystem services to influence decision-making processes. This research has been dominated by the disciplines of ecology and economics with the underlying assumption that the integration of these disciplinary approaches will provide the necessary operational pathways forward. The perspectives of ecology and economics are crucial but the unique qualities of ecosystem services suggest the need to consider other approaches and a willingness to look beyond existing models and disciplinary boundaries. I propose a landscape approach to ecosystem services in which they play a role in the intentional coevolution of social/ ecological systems. I apply this approach to explore the potential for floodplain agricultural landscapes to provide ecosystem services in a 65,000 acre study area located in Oregon's agriculturally-dominated southern Willamette Valley. The landscape's biophysical processes are represented by three ecosystem services: non-structural flood storage, carbon sequestration and floodplain forest. These are quantitatively evaluated using a geographic information system. One aspect of the landscape's sociocultural processes is explored through qualitative interviews with farmers and profiles of the crops they commonly grow. The biophysical and sociocultural research components are integrated through an alternative futures framework to compare the ca. 2000 landscape with a 2050 future landscape in which agricultural production includes ecosystem services. In the 2050 landscape, the synthesis results show where all three ecosystem services are simultaneously provided on 2,981 acres, and where increases in carbon sequestration and floodplain forest are simultaneously provided on an additional 4,841 acres. For the identified acres, the annual income from present-day conventional crop production is provided as a first approximation of the monetary income that farmers would consider for producing ecosystem services.
5

Ekosystemtjänstförvaltning i Sveriges kommuner : En jämförelse mellan tätort och glesbygd

Sporrong, Johan January 2016 (has links)
The concept of ecosystem services often is defined as a way where we as humans protect and preserve available ecosystems and at the same time can make use of these ecosystems for our own well-being. According to the UN report Millennium Ecosystem Assessment from 2005 the services can be classified into four categories: provisioning, regulating, cultural or supporting. This study is focusing on how Swedish municipalities are managing all of these services. The main aim was to examine if there is a difference among municipalities in general and between municipalities with a high and a low range of population density in particular. The reason for these potential differences was also discussed by interviews with representatives for a number of selected municipalities, complemented by studies of literature, this study showed that there are differences between Sweden’s more populated and less populated municipalities. Typically, the main difference was found in the area of the knowledge and the use of the concept in daily planning. Some municipalities seems to be almost unaware of that they partly already are planning for the maintenance of these services. In conclusion, there is still more work to do fully make use of the ecosystem service concept in planning to create a more resilient society, not least for the municipalities on the country side!
6

Use of phytometers for evaluating ecological restoration

Dietrich, Anna L. January 2013 (has links)
The increase in ecological restoration can be attributed to valuation of healthyecosystems and concerns for future climate changes. Freshwaters belong among theglobally most altered ecosystems and are restored to counteract human impacts.Many Swedish streams that were channelized to facilitate timber floating have beenrestored by returning boulders and reconnecting riparian with instream habitats.Evaluation of restoration lacks reliable indicators of organism performance, possiblydue to the complexity of ecosystem responses. Phytometers, i.e. standardized plantstransplanted to different environments, are important indicators of restorationsuccess. Phytometers integrate multiple environmental factors and measureecosystem functions directly. This thesis combines a literature review with threeexperiments and focuses on phytometer use for evaluating ecological restoration. Werecommend using different phytometer species, life-forms and life-stages and longexperiments (>1 year) to obtain high resolution and generality (I). In greenhouse andfield experiments we investigated the effect of restoring channelized rivers onphytometers and abiotic variables in the riparian zone. We hypothesized thatphytometer performance varies with stream size and climate. In the greenhouse, weanalysed differences in fertility between channelized and restored reaches by growingphytometers on soils from experimental sites (II). Phytometers grew better on soilsfrom restored sites in small streams, indicating a positive effect of restoration on soil.We detected this effect already 3-7 years after restoration, suggesting a fasterrecovery than predicted. In a short-term field experiment focusing on germinationand establishment of sunflowers, seedling survival, substrate availability, and soilnutrient content in large streams were enhanced by restoration (III). Overall,phytometers performed best at high altitudes and short growing seasons. The use ofMolinia caerulea and Filipendula ulmaria as phytometers in a long-term fieldexperiment (IV) revealed a better performance at restored sites. One reason was thatsummer flow-variability was higher, particularly in medium-sized streams. Sincephytometers allocated more biomass to belowground parts at restored compared tochannelized sites, it seems important to separate above- and belowground biomass inrestoration evaluation. Restoration outcomes vary with location in the catchment.Knowing such potentially different responses could guide restorationists in where tolocate restoration to be effective or successful. We suggest that small streams reactparticularly fast to restoration. Given that the proportion of small streams is high andthat restoration success in headwaters may favour downstream reaches, werecommend restoration to begin in tributaries to larger rivers. It is not always knownwhy phytometers react the way they do. Greenhouse experiments can disentangle thecauses of phytometer responses in the field by focusing on single environmentalfactors. We demonstrate that phytometers integrate ecosystem responses torestoration by reflecting how environmental factors affect plants under fieldconditions. Further studies are needed to better understand the underlyingmechanisms.
7

Public values for restoring natural ecosystems investigation into non-market values of anadromous fish and wildfire management /

Kaval, Pamela. January 2004 (has links)
Thesis (Ph. D.)--Colorado State University, 2004. / Includes bibliographical references.
8

Ecosystem Learning Center in Umeå

Johansson, Linnea January 2018 (has links)
No description available.
9

Exploration of economic and ecological methods for the assessment of deep-sea and coastal ecosystem services

Jobstvogt, Niels January 2014 (has links)
Marine ecosystems and the ecosystem services they provide have declined dramatically over the last century. In principle, assessing ecosystem services and highlighting their value can help balancing marine conservation and socio-economic goals in environmental decision making. However, in particular for deep-sea ecosystem services many research gaps remain due to methodological challenges involved in their assessment. This thesis advances the research field by assessing economic non-market and non-use values of coastal and deep-sea biodiversity. Stated preference methods were applied along with a Delphi-based expert assessment. In the first choice experiment, participants were willing to pay between £70 and £77 annually for scenarios protecting deep-sea organisms and for medicinal products from deep-sea areas, an environment that participants were mostly unfamiliar with. The second stated preference survey with experienced marine users estimated a stewardship willingness to pay between £8.83 and £8.29 as one-off payments to protect marine sites from degradation. User-preferences were influenced by a broad range of marine habitats, accessibility and the presence of iconic species. The economic value of protected sites decreased when recreational users were excluded. In the third case study, an ecological method − the Ecosystem Principles Approach − was able to alleviate some uncertainties in submarine canyon ecosystem functioning. Ecosystem principles were developed that described spatial, temporal and causal links between processes, such as transportation processes, and important ecosystem services in submarine canyons. The stated preference case studies provide evidence for the less tangible economic trade-offs in protecting marine areas and partly answer the question of how ecosystem services can be assessed using economic tools to inform marine management priorities. The Ecosystem Principles Approach can help us to understand better how to move towards such management priorities.
10

Integrating monetary and non-monetary approaches to the assessment of shared, plural and cultural values of ecosystem services

Kenter, Jasper Onno January 2014 (has links)
There are increasing concerns that monetary valuation of ecosystem services using conventional individualistic methods is not fully able to express the value that people attach to the natural environment. For example, people have values in relation to nature that are not instrumental, but relate to rights, duties and virtues, which are difficult to translate into preferences and willingness-to-pay. Also, the notions of ‘services' and ‘benefits' do not fully reflect the intricate relationships between people and nature. Values and meanings are not necessarily individualistic and given, but are often implicit, shared and shaped through social processes of information sharing, moralisation and democratic debate. This thesis develops a theoretical framework for assessing plural, shared and cultural values of ecosystems and provides a range of case studies to operationalize them for decision-making. The theoretical framework conceptualises values across the dimensions of value concept, provider, process, scale and intention, and identifies seven non-mutually exclusive types of shared values: transcendental, cultural/societal, communal, group, deliberated and other-regarding values, and value to society. A novel model is developed to describe how different values interrelate in deliberative processes: the Deliberative Value Formation model (DVF). This framework underpins two local and two UK-wide case studies, which employ, develop and evaluate a wide range of economic and non-economic, deliberative, interpretive and psychometric methods. Findings indicate that deliberated group values were more considered, more strongly anchored onto the value of benefits and less an expression of ‘gesturing', while at the same time more reflective of transcendental values of participants such as responsibility and social justice. Thus, group-based, deliberative assessments may provide a more robust approach to assessing values than conventional individual valuation. Disciplinary integration provides a richer and more comprehensive evidence base for environmental decision-making and management than the use of single discipline approaches, which is of particular importance for complex and contested contexts.

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