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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.
161

Assessing Monetary Valuation Methodologies for Estimating the Impacts of Climate Change in the Laguna de Rocha (Uruguay)

Fanning, Andrew L. 02 April 2012 (has links)
The motivation for this study arose from the dual observation that there are very few estimates of the local costs of climate change in developing countries and that the few studies that do exist rarely take into account the non-market value of ecosystem services. Using a case study of a coastal lagoon ecosystem in Uruguay, I explore practical reasons for why this might be the case. Informational difficulties related to identifying local climate trends and the identification of ecosystem services as well as the relevance and feasibility of monetary valuation methodologies are discussed using specific examples. Three valuation methodologies are implemented to estimate the monetary values of climate change impacts on specific ecosystem services. The results suggest that climate change is affecting the economic value of the coastal lagoon ecosystem. Implications for local management and lessons learned from the case study are discussed.
162

Ottawa's urban forest : a geospatial approach to data collection for the UFORE/i-Tree eco ecosystem services valuation model

Palmer, Michael 25 March 2013 (has links)
The i-Tree Eco model, developed by the U.S. Forest Service, is commonly used to estimate the value of the urban forest and the ecosystem services trees provide. The model relies on field-based measurements to estimate ecosystem service values. However, the methods for collecting the field data required for the model can be extensive and costly for large areas, and data collection can thus be a barrier to implementing the model for many cities. This study investigated the use of geospatial technologies as a means to collect urban forest structure measurements within the City of Ottawa, Ontario. Results show that geospatial data collection methods can serve as a proxy for urban forest structure parameters required by i-Tree Eco. Valuations using the geospatial approach are shown to be less accurate than those developed from field-based data, but significantly less expensive. Planners must weigh the limitations of either approach when planning assessment projects.
163

Designing an incentive program to reduce on-farm deforestation in the East Usambara Mountains, Tanzania

Kaczan, David Unknown Date
No description available.
164

The Concept of Ecosystem Services : Integrating the concept of ecosystem services on the environmental impact assessment of the Bunge Quarry / :

de Rover, Ted, Persson, Tobias January 2014 (has links)
With the growing awareness and urgency of sustainable business behavior, conducting environmental impact assessments is an important tool for companies to evaluate their impacts. However, the assessment tool has received critique over the last years, and seems not to accomplish its goal to assure a sustainable development and use of the environment. In this thesis, the possibility of integrating the concept of ecosystem services in an environmental impact assessment is investigated. The aim of this study was to create a theoretical framework that facilitates the decision making process of impact assessments with the dimension of ecosystem services. This research is based on an empirical analysis surrounding the environmental assessment of the Bunge Area on Gotland, Sweden by the Finnish mining company Nordkalk AB, together with the legal decision making process that derived from it. The theoretical framework was tested upon applicability, and resulted into providing information concerning the integration of ecosystem services on the environmental impact assessment.
165

Ecosystem Services Based Evaluation Framework of Land-use Management Options for Dryland Salinity in the Avon Region, Western Australian Wheatbelt

Kleplova, Klara Zoe January 2014 (has links)
Dryland-salinity management options aim to positively influence the adverse human-induced processes which lead to salinisation of top-soil. Specifically, the processes causing dryland-salinity are rising saline groundwater table and soil erosion. In the Avon region of Western Australia, the management options are evaluated solely on the basis of their efficiency in lowering groundwater tables. However, recently the need to take into account also their wider impact on the ecosystems' resilience has been recognised as well. Nevertheless, the tool to assess these impacts is missing. The aim of this thesis is to synthesise the missing tool from existing ecosystem services-based land-use evaluation frameworks, which would fit the environmental issue, regional socio-economic demands and the existing dryland salinity management options' efficiency evaluation framework. The thesis builds on secondary data and describes (i) the environmental issue of dryland salinity in Australia, (ii) the dryland salinity-environmental, economic, social and political environments of the Avon region, and (iii) five chosen evaluation frameworks which assess the impact of land-use on ecosystem resilience. The proposed optimal framework for the Avon region is then a combination of two existent frameworks: (i) ecosystem resilience evaluation framework & (ii) the ecosystem services economic valuation framework. Where the inputs of the proposed optimal framework are: (i) soil properties, (ii) external natural and anthropogenic drivers and (iii) beneficiaries; the transfer phase is represented by the soil processes; and the output of the framework are (i) ecosystem services and (ii) their economically valued benefits.
166

Evaluation of coastal protection services provided by nearshore habitats in Cox Bay, Vancouver Island, British Columbia, Canada

Christensen, Lisa 14 May 2014 (has links)
>Coastal and marine resources have been in global decline the past three decades. Research suggests that the decline is due to an undervaluation of ecosystem services. The Natural Capital Project (Natcap) has developed models to assess the impact of human activities on the sustained delivery of ecosystem services within terrestrial and marine environments. With the use of Natcap models, this case study (located at Cox Bay, Vancouver Island, British Columbia, Canada), examined coastal protection services provided by nearshore habitats, and provides an economic valuation of these services. The model results indicate that nearshore habitats do play a role in reducing coastal vulnerability and coastal erosion, with an "avoided damages" cost of $1 million. Sand dunes provided the greatest amount of coastal protection, whereas seagrasses were found to have a negligible effect. These outcomes can inform policy and decision makers about trade-offs regarding habitat protection, coastal development and climate change adaptation.
167

Material exchange in mangroves during tidal inundation

Maria Adame Vivanco Unknown Date (has links)
Coastal wetlands dominated by mangroves provide important ecological services to the coastal zone, many of which are associated with tidal inundation . In this study I investigated whether all coastal wetlands provide similar ecosystem services, or whether these varied depending on their geomorphological setting and the eutrophication level of the floodwater. Sampling was conducted over two years with significantly different levels of rainfall over six estuaries in Southeast Queensland, Australia. Sediment, nutrient and carbon exchange were investigated in tidal and riverine estuaries dominated by mangrove forests. The estuaries selected also comprised a gradient from low mesotrophic to low eutrophic. Spatial variation within the coastal wetlands was also investigated, comparing nutrient exchange in the low and high intertidal cyanobacteria mat . To assess sediment exchange, I measured retention of total suspended solids and sedimentation rates. Additionally, in order to assess the origin of sediment deposited in mangroves, glomalin, a novel terrestrial soil carbon (C) tracer, was used. Nutrient and C exchange were quantified by comparison of concentrations of soluble reactive phosphorus (SRP), nitrogen oxides (NOx--N), ammonium (NH4+) total organic carbon (TOC) and dissolved organic C (DOC) in water entering and leaving the mangroves during complete tidal cycles (3 tidal cycles in 6 estuaries for 2 years). Finally, the biogeochemical function of the cyanobacteria mat was measured through experiments investigating nitrogen fixation (N) and nutrient exchange in the extensive mats in the Exmouth Gulf, Western Australia. My results show that the seaward fringe mangrove retains the majority of sediment entering the wetland during a tidal cycle accounting for 52.5 ± 12.5 % of the total sedimentation (fringe mangrove + scrub mangrove + saltmarsh/ cyanobacteria mat). Geomorphological setting had a stronger influence on spatial patterns of deposition than on sedimentation rates. Riverine mangroves had more homogeneous distribution of sediments across the intertidal zone than tidal mangroves, where most sedimentation occurred in the seaward fringe mangrove zone. The presence of glomalin in sediments, and thus the relative importance of terrigenous sediment, was strongly influenced by geomorphological setting. Glomalin was primarily delivered to riverine mangroves and deposited within the scrub mangrove zone, while tidal mangroves received less glomalin during tidal inundation and most of it was deposited within the fringe mangrove zone. Overall, NOx--N concentrations decreased in the floodwater after flooding the coastal wetland, suggesting that these ecosystems act as sinks of dissolved NOx--N during tidal inundation. In average, NOx--N concentrations in the floodwater decreased 28 %. Additionally, during periods of high rainfall the decrease in nutrient concentrations was more pronounced, and not only NOx--N but also SRP and NH4+ concentrations decreased to up to 51 % and 83 %, respectively. My results suggest that rainfall enhances nutrient removal by coastal wetlands in the region. Geomorphological setting also affected nutrient removal. Riverine mangroves received stronger nutrient pulses, which resulted in strongest rates of nutrient removal during tidal inundation. Nutrient removal was closely related to the nutrient concentration of the floodwater: high nutrient removal occurred when floodwater was rich in nutrients. The C entering the wetland in the floodwater was mainly composed of DOC and its exchange did not vary among sites with differing geomorphological setting. However, DOC exchange was strongly affected by the water quality of floodwater inundating the coastal wetland. DOC concentrations were higher in the flood compared to the ebb tide in sites flooded by water high in C, NH4+ and SRP, suggesting DOC import. Contrary, DOC concentrations were lower in the flood compared to the ebb tide in sites flooded by water high in C, NH4+ and SRP, suggesting DOC export. The high intertidal cyanobacteria mat was important in regulating N fluxes in coastal wetlands. In the arid Exmouth Gulf, where cyanobacteria mats are abundant, nitrogen fixation rates were 4.9 ± 3.2 nmol cm-1 h-1. Cyanobacteria mats also removed N from the floodwater in the form of NOx--N (0.47 ± 0.45 g m-2 h-1) and NH4+ (0.31 ± 0.02 g m-2 h-1). N fixation and nutrient removal from the floodwater was highly variable spatially and temporally. N fixation rates were highest during the day in the mat situated at low tidal elevations. Overall, I found that the material exchange in coastal wetlands is variable within the coastal zone as a result of natural factors, such as geomorphology, vegetation composition and rainfall. But material exchange in wetlands is also affected by anthropogenic factors, particularly eutrophication. From all these factors, eutrophication of the floodwater appears to be the most critical, shifting the mangrove function from a DOC source to a nutrient and DOC sink. Approximate thresholds of nutrient and C concentrations in the floodwater that are likely to trigger shifts in ecosystem function in coastal wetlands in Southeast Queensland, and thus in the ecosystem services they provide, are 0.02 mg L-1 of SRP, 0.04 mg L-1 of NH4+ and 7.5 mg L-1 of DOC.
168

Material exchange in mangroves during tidal inundation

Maria Adame Vivanco Unknown Date (has links)
Coastal wetlands dominated by mangroves provide important ecological services to the coastal zone, many of which are associated with tidal inundation . In this study I investigated whether all coastal wetlands provide similar ecosystem services, or whether these varied depending on their geomorphological setting and the eutrophication level of the floodwater. Sampling was conducted over two years with significantly different levels of rainfall over six estuaries in Southeast Queensland, Australia. Sediment, nutrient and carbon exchange were investigated in tidal and riverine estuaries dominated by mangrove forests. The estuaries selected also comprised a gradient from low mesotrophic to low eutrophic. Spatial variation within the coastal wetlands was also investigated, comparing nutrient exchange in the low and high intertidal cyanobacteria mat . To assess sediment exchange, I measured retention of total suspended solids and sedimentation rates. Additionally, in order to assess the origin of sediment deposited in mangroves, glomalin, a novel terrestrial soil carbon (C) tracer, was used. Nutrient and C exchange were quantified by comparison of concentrations of soluble reactive phosphorus (SRP), nitrogen oxides (NOx--N), ammonium (NH4+) total organic carbon (TOC) and dissolved organic C (DOC) in water entering and leaving the mangroves during complete tidal cycles (3 tidal cycles in 6 estuaries for 2 years). Finally, the biogeochemical function of the cyanobacteria mat was measured through experiments investigating nitrogen fixation (N) and nutrient exchange in the extensive mats in the Exmouth Gulf, Western Australia. My results show that the seaward fringe mangrove retains the majority of sediment entering the wetland during a tidal cycle accounting for 52.5 ± 12.5 % of the total sedimentation (fringe mangrove + scrub mangrove + saltmarsh/ cyanobacteria mat). Geomorphological setting had a stronger influence on spatial patterns of deposition than on sedimentation rates. Riverine mangroves had more homogeneous distribution of sediments across the intertidal zone than tidal mangroves, where most sedimentation occurred in the seaward fringe mangrove zone. The presence of glomalin in sediments, and thus the relative importance of terrigenous sediment, was strongly influenced by geomorphological setting. Glomalin was primarily delivered to riverine mangroves and deposited within the scrub mangrove zone, while tidal mangroves received less glomalin during tidal inundation and most of it was deposited within the fringe mangrove zone. Overall, NOx--N concentrations decreased in the floodwater after flooding the coastal wetland, suggesting that these ecosystems act as sinks of dissolved NOx--N during tidal inundation. In average, NOx--N concentrations in the floodwater decreased 28 %. Additionally, during periods of high rainfall the decrease in nutrient concentrations was more pronounced, and not only NOx--N but also SRP and NH4+ concentrations decreased to up to 51 % and 83 %, respectively. My results suggest that rainfall enhances nutrient removal by coastal wetlands in the region. Geomorphological setting also affected nutrient removal. Riverine mangroves received stronger nutrient pulses, which resulted in strongest rates of nutrient removal during tidal inundation. Nutrient removal was closely related to the nutrient concentration of the floodwater: high nutrient removal occurred when floodwater was rich in nutrients. The C entering the wetland in the floodwater was mainly composed of DOC and its exchange did not vary among sites with differing geomorphological setting. However, DOC exchange was strongly affected by the water quality of floodwater inundating the coastal wetland. DOC concentrations were higher in the flood compared to the ebb tide in sites flooded by water high in C, NH4+ and SRP, suggesting DOC import. Contrary, DOC concentrations were lower in the flood compared to the ebb tide in sites flooded by water high in C, NH4+ and SRP, suggesting DOC export. The high intertidal cyanobacteria mat was important in regulating N fluxes in coastal wetlands. In the arid Exmouth Gulf, where cyanobacteria mats are abundant, nitrogen fixation rates were 4.9 ± 3.2 nmol cm-1 h-1. Cyanobacteria mats also removed N from the floodwater in the form of NOx--N (0.47 ± 0.45 g m-2 h-1) and NH4+ (0.31 ± 0.02 g m-2 h-1). N fixation and nutrient removal from the floodwater was highly variable spatially and temporally. N fixation rates were highest during the day in the mat situated at low tidal elevations. Overall, I found that the material exchange in coastal wetlands is variable within the coastal zone as a result of natural factors, such as geomorphology, vegetation composition and rainfall. But material exchange in wetlands is also affected by anthropogenic factors, particularly eutrophication. From all these factors, eutrophication of the floodwater appears to be the most critical, shifting the mangrove function from a DOC source to a nutrient and DOC sink. Approximate thresholds of nutrient and C concentrations in the floodwater that are likely to trigger shifts in ecosystem function in coastal wetlands in Southeast Queensland, and thus in the ecosystem services they provide, are 0.02 mg L-1 of SRP, 0.04 mg L-1 of NH4+ and 7.5 mg L-1 of DOC.
169

Material exchange in mangroves during tidal inundation

Maria Adame Vivanco Unknown Date (has links)
Coastal wetlands dominated by mangroves provide important ecological services to the coastal zone, many of which are associated with tidal inundation . In this study I investigated whether all coastal wetlands provide similar ecosystem services, or whether these varied depending on their geomorphological setting and the eutrophication level of the floodwater. Sampling was conducted over two years with significantly different levels of rainfall over six estuaries in Southeast Queensland, Australia. Sediment, nutrient and carbon exchange were investigated in tidal and riverine estuaries dominated by mangrove forests. The estuaries selected also comprised a gradient from low mesotrophic to low eutrophic. Spatial variation within the coastal wetlands was also investigated, comparing nutrient exchange in the low and high intertidal cyanobacteria mat . To assess sediment exchange, I measured retention of total suspended solids and sedimentation rates. Additionally, in order to assess the origin of sediment deposited in mangroves, glomalin, a novel terrestrial soil carbon (C) tracer, was used. Nutrient and C exchange were quantified by comparison of concentrations of soluble reactive phosphorus (SRP), nitrogen oxides (NOx--N), ammonium (NH4+) total organic carbon (TOC) and dissolved organic C (DOC) in water entering and leaving the mangroves during complete tidal cycles (3 tidal cycles in 6 estuaries for 2 years). Finally, the biogeochemical function of the cyanobacteria mat was measured through experiments investigating nitrogen fixation (N) and nutrient exchange in the extensive mats in the Exmouth Gulf, Western Australia. My results show that the seaward fringe mangrove retains the majority of sediment entering the wetland during a tidal cycle accounting for 52.5 ± 12.5 % of the total sedimentation (fringe mangrove + scrub mangrove + saltmarsh/ cyanobacteria mat). Geomorphological setting had a stronger influence on spatial patterns of deposition than on sedimentation rates. Riverine mangroves had more homogeneous distribution of sediments across the intertidal zone than tidal mangroves, where most sedimentation occurred in the seaward fringe mangrove zone. The presence of glomalin in sediments, and thus the relative importance of terrigenous sediment, was strongly influenced by geomorphological setting. Glomalin was primarily delivered to riverine mangroves and deposited within the scrub mangrove zone, while tidal mangroves received less glomalin during tidal inundation and most of it was deposited within the fringe mangrove zone. Overall, NOx--N concentrations decreased in the floodwater after flooding the coastal wetland, suggesting that these ecosystems act as sinks of dissolved NOx--N during tidal inundation. In average, NOx--N concentrations in the floodwater decreased 28 %. Additionally, during periods of high rainfall the decrease in nutrient concentrations was more pronounced, and not only NOx--N but also SRP and NH4+ concentrations decreased to up to 51 % and 83 %, respectively. My results suggest that rainfall enhances nutrient removal by coastal wetlands in the region. Geomorphological setting also affected nutrient removal. Riverine mangroves received stronger nutrient pulses, which resulted in strongest rates of nutrient removal during tidal inundation. Nutrient removal was closely related to the nutrient concentration of the floodwater: high nutrient removal occurred when floodwater was rich in nutrients. The C entering the wetland in the floodwater was mainly composed of DOC and its exchange did not vary among sites with differing geomorphological setting. However, DOC exchange was strongly affected by the water quality of floodwater inundating the coastal wetland. DOC concentrations were higher in the flood compared to the ebb tide in sites flooded by water high in C, NH4+ and SRP, suggesting DOC import. Contrary, DOC concentrations were lower in the flood compared to the ebb tide in sites flooded by water high in C, NH4+ and SRP, suggesting DOC export. The high intertidal cyanobacteria mat was important in regulating N fluxes in coastal wetlands. In the arid Exmouth Gulf, where cyanobacteria mats are abundant, nitrogen fixation rates were 4.9 ± 3.2 nmol cm-1 h-1. Cyanobacteria mats also removed N from the floodwater in the form of NOx--N (0.47 ± 0.45 g m-2 h-1) and NH4+ (0.31 ± 0.02 g m-2 h-1). N fixation and nutrient removal from the floodwater was highly variable spatially and temporally. N fixation rates were highest during the day in the mat situated at low tidal elevations. Overall, I found that the material exchange in coastal wetlands is variable within the coastal zone as a result of natural factors, such as geomorphology, vegetation composition and rainfall. But material exchange in wetlands is also affected by anthropogenic factors, particularly eutrophication. From all these factors, eutrophication of the floodwater appears to be the most critical, shifting the mangrove function from a DOC source to a nutrient and DOC sink. Approximate thresholds of nutrient and C concentrations in the floodwater that are likely to trigger shifts in ecosystem function in coastal wetlands in Southeast Queensland, and thus in the ecosystem services they provide, are 0.02 mg L-1 of SRP, 0.04 mg L-1 of NH4+ and 7.5 mg L-1 of DOC.
170

BOSTADENS NÄRMILJÖ I ETT HÅLLBARHETSPERSPEKTIV / RESIDENTIAL YARDS AND THEIR ROLE FOR SUSTAINABLE DEVELOPMENT

Danielsson, Cristina January 2014 (has links)
A majority of Sweden’s population, about 80 %, lives in urban environments, and a majority of them live in residential complexes with shared residential yards. People spend a large part of their time in or around their home, which is why the outside environment and the green space in the area play an important part in a person’s well being. The green yard offers space for children’s activities, recreation, solitude, relaxation and gardening and gives the opportunity to learn and understand nature and its processes. The green yard also constitutes a part of the city’s factual green structure, informal green spaces that are not owned by the city and are therefore not included in the formal planning processes. The green residential yards also provide a number of ecosystem services such as climate regulation, purification of water and air and rainwater infiltration, all of which are of importance in the fight against climate change. The goal of this thesis has been to present the advantages an improved planning and maintenance of the urban green space and the residential yard in particular can offer. A number of important properties and functions that affect a yard’s functionality and how it is perceived are also presented and explained. The paper also aims to offer a better understanding of the garden’s role in improving the social conditions in the neighbourhood, and of the importance of involving the residents in planning and maintaining the green spaces. A number of case studies and analyses offer a more concrete perspective on the real world situations, and of successful refurbishment projects. Involving the residents in the formal planning and building processes has been proved to have positive effects on revitalising areas such as Gårdsten in Göteborg. Tenant involvement in open space management can lead to a positive spiral where people start caring for and identifying themselves with their neighbourhood, which can reduce the degree of stigmatisation and marginalisation.

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