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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.
141

Modelling adaptation strategies for Swedish forestry under climate and global change

Blanco González, Víctor January 2017 (has links)
Adaptation is necessary to cope with, or take advantage of, the effects of climate change on socio-ecological systems. This is especially important in the forestry sector, which is sensitive to the ecological and economic impacts of climate change, and where the adaptive decisions of owners play out over long periods of time. These decisions are subject to experienced and expected impacts, and depend upon the temporal interactions of a range of individual and institutional actors. Knowledge of, and responses to, climate change are therefore very important if forestry is to cope with, or take advantage of, the effects of climate change over longer timescales. It is important to understand the role of human behaviour and decision-making processes in the study of complex socio-ecological systems and modelling is a method that can support experiments to advance this understanding. This study is based on the development of CRAFTY-Sweden; an agent-based model that allows the exploration of Swedish land-use dynamics and adaptation to climate change through scenario analysis. In CRAFTY-Sweden, forest and farmland owners make land use and management decisions according to their objectives, management preferences and capabilities. As a result of their management and location characteristics they are able to provide ecosystem services. To explore future change, quantitative scenarios were used that considered both socio-economic development pathways and climatic change. Simulations were run under the different scenarios for the period 2010-2100, for the whole of Sweden. Furthermore, because institutions (i.e. organisations) also influence socio-ecological systems through their actions and interactions between them and with land owners and the environment, a conceptual model of institutional actions applied to socio-ecological systems was developed. The application of this conceptual model was explored through a model of institutions that can act, interact and adapt to environmental change in attempting to affect ecosystem service provision within a simple forestry governance system. I found that forestry in the future will likely be unable to meet societal demands for forest services solely on the basis of autonomous adaptation. A northward expansion of agriculture and especially of forestry proved positive for both sectors to adapt to changing conditions, under several scenarios, given the substantial land availability and the improved environmental conditions for plant growth. Legacy effects of past land-use change can have a great impact on future land-use change and adaptation processes, especially in forestry. Also, greater competition for land may lead to shorter forest rotation times. Socio-economic change and land owner behavioural differences may have a larger impact on owner competitiveness, land-use change and ecosystem service provision than climate-driven changes in land productivity. Different owner objectives and behaviour resulted in different levels of ecosystem service provision. Also, particular forest types were differently suitable for adaptation depending on the sets of objectives under which they were managed. Owners implementing particular management strategies can be differently competitive under different future scenarios, and the suitability of such strategies for adaptation is not a static, inherent characteristic of a system. Instead, it evolves in response to changing contexts that include both the external global change drivers and the internal dynamics of agent interactions. Additionally, institutional conceptual models as presented here can support better understanding of the key institutional decision-making dynamics and their consequences, endogenously, flexibly across different socio-ecological systems. Finally, study limitations, future research and the policy relevance of findings are discussed.
142

Résilience des services écosystémiques à l’échelle du paysage : un cadre conceptuel et une analyse pour un socio-écosystème de montagne / Resilience of ecosystem services at landscape scale : Conceptual framework and analysis for a mountain socio-eco-system

Devaux, Caroline 01 March 2016 (has links)
L’intérêt que porte la communauté scientifique ainsi que politique aux les services écosystémiques et à leur résilience face aux changements globaux (environnementaux ou sociétaux) en cours est grandissant, ce qui se reflète par le nombre d’études à ce sujet, le rapport d’évaluation des écosystèmes pour le millénaire et la mise en place d’un groupe de travail sur la résilience (« Resilience Alliance »). Les définitions de la résilience sont elles aussi très variées, avec des concepts tels que la résistance, la résilience spécifique (« de quoi à quoi ? »), la résilience générale, l’adaptabilité et la transformabilité, que nous nous sommes appropriés dans le but de développer un cadre conceptuel et méthodologique pour étudier la résilience de la fourniture de services écosystémiques, en particulier dans le but de comparer les potentiels de résilience des différents types de prairies subalpines du col du Lautaret (Hautes-Alpes, France) pour un ensemble de services sélectionnés. Nous avons proposé deux approches pour évaluer les potentiels de résilience des différents états dans lequel peut se trouver un socio-écosystème, en considérant la résilience comme la capacité d’un système à maintenir une fourniture stable de services écosystémiques (composante résistance) mais aussi sa capacité à l’adapter (différentes composantes selon le degré d’adaptation : résilience, transition, transformation). Une première étape d’évaluation d’un ensemble de services d’intérêt sur la zone d’étude est suivie d’une première analyse de la résilience de chacun de ces services spécifiquement, basée sur l’évaluation de « gammes opérationnelles » pour chaque service, définies comme les gammes de valeurs que peut prendre le dit service dans un état donné du socio-écosystème. L’échelle organisationnelle à laquelle ces gammes sont évaluées les relie aux différentes composantes de la résilience. Les résultats confirment l’intérêt de s’intéresser à la résilience spécifique de chaque service, car leur profil de résilience sont différents, c’est-à-dire que les prairies aux plus forts potentiels ne sont pas les même d’un site à l’autre, bien que dans tous les cas les potentiels de résilience soient plutôt forts, au contraire des autres potentiels.La deuxième analyse part de l’hypothèse théorique que la diversité des traits de réponse (hétérogénéité et redondance) améliore la résilience. Nous avons fait l’hypothèse que, lorsque les traits de réponse sont ceux utilisés pour modéliser les services écosystémiques, la diversité fonctionnelle d’une communauté végétale peut-être reliée à sa résilience générale en termes de services écosystémiques. Nous avons relié plusieurs mesures de la diversité fonctionnelle aux potentiels de résilience (entropie et diversité fonctionnelle dans leur dimension α et β, redondance et complémentarité des groupes fonctionnels). Cependant, les résultats obtenus par l’analyse des prairies du Lautaret nous amènent à réfuter l’hypothèse proposant que la diversité fonctionnelle des communautés végétales permet d’expliquer le profil de résilience des services écosystémiques analysés, car ils ne concordent pas avec les profils de résilience trouvés par l’approche des gammes opérationnelles. Au final, nous préconisons d’utiliser l’approche des gammes opérationnelles, qui permet de connaître le profil de résilience de chaque service, dans le cadre d’étude portant sur la capacité d’un socio-écosystème à maintenir la fourniture de ses services écosystémiques. Cette approche peut de plus être enrichie d’une approche de scénarisation qui permettrait de déterminer « à quoi » la fourniture de chaque service est résiliente. / As evidenced by the number of studies on the subject, the recent millennium ecosystem assessment and the establishment of a working group on resilience (« Resilience Alliance »), the interest of the scientific community in ecosystem services and their resilience in the face of global change (environmental or social) is steadily increasing. Definitions of resilience are highly varied, and we used concepts such as resistance, specific resilience (« of what to what ? »), generalised resilience, adaptability and transformability to develop a conceptual and methodological framework to study the resilience of ecosystem service provision. This conceptual framework was applied to compare the potential resilience of differing sub-alpine grasslands types in three local government areas in the area of the Col du Lautaret (Hautes-Alpes, France) for a number of locally and regionally important ecosystem services. We proposed two approaches for evaluating the potential resilience of the different states in which a socio-ecosystem can exist, by considering resilience as the capacity of a system to maintain a stable provision of an ecosystem service (resistance component), as well as its capacity to adapt this provision if needed (components of resilience, transition, transformation depending on the degree of adaptation). A first stage of the quantification of ecosystem services was followed by an initial analysis of each of these services via the evaluation of their « operating ranges », defined as the range of values that a service can take given a particular state of the socio-ecosystem. The organizational scale at which these ranges are evaluated links them to other components of resilience. Our results confirm the utility of considering the specific resilience of each service, as the profiles of their resistance are different. In particular, the types of grasslands with the highest resilience component potential are not the same from one site to another, even though in all cases these resilience component potentials are rather high as compared to other components potentials. The second analysis is based on the theoretical hypothesis that it is the increasing diversity of response traits (heterogeneity and redundancy) which increases resistance. We hypothesised that, when it is response traits that have been used to model ecosystem services, the functional diversity of a plant community can be linked to its overall resistance in terms of ecosystem services. We linked a number of measures of functional diversity to resilience potential, including the α and β dimensions of entropy and functional diversity, and the redundancy and complementarity of functional groups. The obtained results for the grasslands at Lautaret lead us to reject the hypothesis which proposes that the functional diversity of plant communities can be used to predict the patterns of resilience of the analysed ecosystem services, as these do not correspond to the patterns of resistance obtained from the approach using operating ranges. Finally, we suggest that to assess the capacity of a socio-ecosystem to maintain the provision of ecosystem services, our approach using operating ranges is preferable as it allows for the quantification of the resistance profile of each service. This approach could be further developed using scenario building so as to determine « to what » the provision of each service is resistant.
143

A cegueira do Ãbvio: a importÃncia dos serviÃos ecossistÃmicos na mensuraÃÃo do bem-estar / The blindness of obvious: the relevance of ecosystem services in the measurement of well - being

Melca Silva Rabelo 30 April 2014 (has links)
Deutscher Akademischer Austausch Dienst / Diante da crise ambiental global, os ecossistemas tornam-se cada vez mais vulnerÃveis, e consequentemente os benefÃcios por eles ofertados, conhecidos como serviÃos ecossistÃmicos. Os ServiÃos EcossistÃmicos influenciam de maneira direta e indireta a promoÃÃo de bem-estar humano. Seus benefÃcios atravessam fronteiras, mas a sua produÃÃo pode acontecer de maneira local, cujo processo ainda à pouco entendido pelos cientistas. Durante anos, tÃm sido negligenciados, principalmente pelos paÃses com pouco conhecimento e interesse sobre sua prÃpria biodiversidade. PorÃm, o desafio de se conviver em um planeta finito e com uma populaÃÃo mundial cada vez maior anuncia um cenÃrio em que o impacto crescente sobre o uso dos recursos naturais impulsionarà a necessidade de se investir em uma gestÃo eficiente sobre sua alocaÃÃo. O presente trabalho parte da hipÃtese de a mensuraÃÃo do bem-estar, pela perspectiva do desenvolvimento sustentÃvel, deve ser composta por indicadores que contemplem a integraÃÃo entre o bem-estar humano e os serviÃos ecossistÃmicos. O objetivo geral da pesquisa foi propor um conjunto de indicadores que retrate, pela perspectiva do desenvolvimento sustentÃvel, a importÃncia da inserÃÃo dos serviÃos ecossistÃmicos de provisÃo na mensuraÃÃo do bem-estar em Ãreas degradadas. Essa relaÃÃo traz em si o Ãbvio: a importÃncia dos serviÃos ecossistÃmicos para o bem-estar humano. Baseando-se em uma releitura de Prescott-Allen (2001) e adaptando para a realidade local, foi desenvolvido um conjunto de Ãndices e indicadores, em diferentes dimensÃes, que resultaram em dois Ãndices: Ãndice de Bem-Estar Humano (IBEH) e Ãndice de Bem-Estar EcossistÃmico (IBEE). O IBEH à composto por cinco dimensÃes (SaÃde e PopulaÃÃo, Riqueza das FamÃlias, Conhecimento e Cultura, Comunidade e Equidade) e quinze indicadores, enquanto o IBEE à constituÃdo por cinco dimensÃes (Terra, Ãgua, Ar, Biodiversidade e Uso dos Recursos) e sete indicadores gerando assim um framework que reproduz o seu estado e suas inter-relaÃÃes. A validaÃÃo do IBEH e do IBEE foi realizada na comunidade do SÃtio do Brum localizado no bioma Caatinga no estado do CearÃ, Brasil. Desconhecido para muitos, a Caatinga està em acelerado processo de degradaÃÃo intensificado pela mà gestÃo dos recursos ambientais bem como pelas condiÃÃes climÃticas da regiÃo. Como principais resultados o uso de Ãndices e indicadores em serviÃos ecossistÃmicos conseguiu capturar a relaÃÃo entre os serviÃos ecossistÃmicos e o bem-estar humano, alÃm de validar a capacidade dos indicadores escolhidos descreverem os sistemas sÃcio-ecossistÃmicos e a sua interaÃÃo. A escolha da aplicaÃÃo dos Ãndices em um bioma degradado e por diversas vezes pouco valorizado, como a Caatinga, revelou nÃo somente a importÃncia do impacto das aÃÃes antrÃpicas neste tipo de bioma, mas o vÃu que os cobre. Identificou-se uma comunidade que compreende sua realidade, almeja mudanÃas, possui visÃo de futuro coletiva, mas nÃo possui capacidade de provocar mudanÃas. Embora nÃo seja fÃcil agir em funÃÃo das preocupaÃÃes intergeracionais, mudanÃas somente ocorrerÃo quando as avaliaÃÃes de serviÃos ecossistÃmicos englobarem tambÃm as pessoas, algo que por sua vez envolve motivaÃÃes e limites cognitivos na aquisiÃÃo e processamento de informaÃÃes, essencial para garantir o bem-estar das geraÃÃes presentes e futuras, abordagem sugerida pelo framework em questÃo apresentado. / Given the global environmental crisis, ecosystems become increasingly vulnerable and therefore the benefits offered by them, known as ecosystem service. The ecosystem services influence directly and indirectly the promotion of human well-being. Its benefits cross borders, but its production can happen in a local way, which process is still poorly understood by scientists. For years, the ecosystem services have been neglected, especially by countries with little knowledge and interest about their own biodiversity. However, the challenge to live in a finite planet with a growing world population announce a scenario where increasing impact on the use of natural resources will drive the need to invest in efficient management of its allocation . This study starts from the hypothesis that the measurement of well-being by the sustainable developmentâs approach would include indicators that address the integration of human well-being and ecosystem services. The main goal of this research is present indices that portray, in a sustainable developmentâs approach, the importance of integrating provisioning ecosystem services in measuring of well-being in degraded areas. This interaction brings with it the obvious: the relevance of ecosystem services for human well-being. Taking into account the literature review, we adapted the Prescott-Allen model to make it appropriate for our study area. A set of indices and indicators were developed in different dimensions resulting in two indices: the Human Well-Being Index (HWBI) and the Ecosystem Well-Being Index (EWBI).The HWBI consists of five dimensions: Health and Population, Household Wealth, Knowledge and Culture, Community and Equity, and fifteen indicators. The EWBI also consists of five dimensions: Land, Water, Air, Biodiversity and Resource Use; and seven indicators. The interaction between these two indices generated a framework that shows the dependence between each of the variables analyzed. The proposed set of indicators was tested in Sitio do Brum community, located in the Caatinga biome in the state of CearÃ, Brazil. Unknown to many, the Caatinga is in a rapid degradation process due to mismanagement of environmental resources and the climatic conditions of the region. The main results of the use of indices and indicators for ecosystem services managed to capture the relationship between ecosystem services and human well-being, and to validate the ability of the chosen indicators to describe the socio-ecosystems and their interaction. The choice of application of the parameters in a degraded and often undervalued biome, such as the Caatinga, revealed not only the importance of the impact of human actions in this type of biome, but the veil that covers them. A community was identified, which understands its reality, craves for changes, has its own collective vision of the future, but has no ability to bring about change. Although it is not easy to act on the basis of intergenerational concerns, changes only occur when the assessments of ecosystem services also encompass people, which in turn involves motivations and cognitive limitations in acquiring and processing information, essential to ensure the well-being of current and next generations, approach suggested by the framework in question.
144

Uma arquitetura de sistemas distribuídos para weblabs de serviços ambientais. / Distributed architecture for weblabs of ecosystem services.

Marcelo Succi de Jesus Ferreira 15 June 2007 (has links)
Serviços Ambientais - purificação do ar, estabilização do clima, polinização de culturas, etc. - são funções fundamentais na sustentação da vida humana e têm sua importância econômica cada vez mais evidenciada. Para melhor estudar estes Serviços e saber como eles se comportam, são necessárias novas abordagens para disponibilizar, integrar e compartilhar os dados existentes sobre eles. O projeto ViNCES (Virtual Network Center of Ecosystem Services) propõe a utilização de laboratórios acessíveis via internet - weblabs - com foco em Serviços Ambientais a fim de promover uma melhor compreensão destes serviços. Assim, com o objetivo de viabilizar esta proposta, desenvolveu-se uma arquitetura que permite o acesso aos diversos weblabs do projeto de maneira integrada, disponibilizando os dados de experimentos realizados a um maior número de pesquisadores. A arquitetura proposta fundamenta-se no paradigma de Arquitetura Orientada a Serviços e atende a requisitos de acesso centralizado aos weblabs para a realização e recuperação de experimentos de maneira remota. Esta arquitetura aproveita outras pesquisas na área de Ecoinformática, considerando soluções já existentes no projeto SEEK (Science Environment for Ecological Knowledge). Desta maneira, adota o padrão de metadados EML (Ecological Metadata Language) para a transferência e armazenamento de dados dos experimentos, permitindo que os experimentos fiquem disponíveis a outros pesquisadores que utilizem a infra-estrutura do projeto SEEK. / Ecosystem Services - air purification, climate estabilization, crop pollination, etc. - are essential to sustain human life.Their economic importance is becoming more and more recognized. In order to better study these Services and learn about their behaviour, new approaches are needed for making available, integrating and sharing existing data about them. The ViNCES (Virtual Network Center of Ecosystem Services) project proposes the use of remotely accessible laboratories - weblabs - focused on Ecosystem Services to better understanding these services. In this way, an architecture was developed that allows access to project´s weblabs in an integrated way, giving access to collected data for more researchers. The proposed architecture is based on the SOA (Service Oriented Architecture) paradigm and considers requirements of centralized access to laboratories to, in a remote way, make experiments and retrieve gathered data. This architecture considers other related initiatives in the ecoinformatics field, and uses solutions present in the SEEK (Science Environment for Ecological Knowledge) project. In this way, the EML (Ecological Metadata Language) standard was adopted for transporting and storaging experiments data, and allows that these data are available for other researchers that use the SEEK infra-structure.
145

Efeitos da estrutura da paisagem sobre o controle biológico do bicho-mineiro-do-cafeeiro (Leucoptera coffeella, Lepidoptera: Lyonetiidae) provido por aves e morcegos / Landscape structure effects on the biological control of the coffee-leaf-miner (Leucoptera coffeella, Lepidoptera: Lyonetiidae) provided by birds and bats

Felipe Miguel Libran Embid 10 June 2015 (has links)
O controle biológico de pragas agrícolas é um dos serviços ecossistêmicos mais valorizados, dada sua importância para a produção agrícola. Embora vários estudos tenham demonstrado que a abundância e riqueza de predadores aumentam com a quantidade de floresta nativa, os mecanismos subjacentes que modulam a relação entre a cobertura florestal e provisão de controle biológico em diferentes escalas espaciais são ainda pouco conhecidos. Neste trabalho, utilizamos experimentos de exclusão de vertebrados voadores em oito paisagens cafeeiras na Mata Atlântica, num gradiente de cobertura florestal, e quantificamos as consequências para a perda foliar e para a frutificação. A perda foliar mostrou uma relação negativa com a cobertura florestal em paisagens com 2 km de raio, indicando que a herbivoria é melhor controlada em paisagens com alta cobertura florestal, especialmente na presença de aves e morcegos. No entanto, no nível local, 300 m ao redor das plantas de café, a perda foliar e a frutificação responderam diferentemente à cobertura florestal. Em unidades com baixa cobertura florestal local, a exclusão de aves e morcegos aumentou a perda foliar e diminuiu a frutificação em uma média de 13%. Por outro lado, em unidades com alta cobertura florestal local, a exclusão de aves e morcegos não teve efeitos significativos nem na perda foliar, nem na frutificação. Concluímos que os efeitos da exclusão de aves e morcegos na perda foliar e frutificação são modulados por diferentes processos que ocorrem no nível local e da paisagem. Sugerimos que quando a cobertura florestal local é alta (geralmente perto de fragmentos florestais), as aves e os morcegos não se alimentam apenas de herbívoros, mas também de mesopredadores. No entanto, quando a cobertura florestal local é baixa (e.g. longe de fragmentos florestais), os mesopredadores não ocorrem e aves e morcegos passam a prover serviço de controle biológico de pragas, alimentando-se principalmente de herbívoros. Destacamos a importância de empregar uma análise multiescalar em sistemas onde espécies com diferentes capacidades de dispersão proveem um serviço ecossistêmico. / Biological control of agricultural pests is one of the most important ecosystem services given its key role for agricultural production. Although several studies have shown that the abundance and richness of predators increase with the amount of native forest in the landscape, the underlying mechanisms relating forest cover at different spatial scales with the provision of biological control are still poorly understood. We experimentally excluded flying vertebrates (birds and bats) in eight coffee landscapes in the Brazilian Atlantic Forest, encompassing a gradient of forest cover and quantified the consequences for coffee leaf loss and fruit set. Leaf loss showed a negative relation with forest cover at landscape level, in landscapes with 2 km radius, indicating that herbivory is better controlled in landscapes with high forest cover, especially in the presence of birds and bats. However, at local level, 300 m around coffee plants, leaf loss and fruit set responded to forest cover differently. In units with low local forest cover exclusion of birds and bats increased leaf loss and reduced fruit set by 13% in mean. However, in units with high local forest cover, exclusion of birds and bats had no significant effect neither on leaf loss nor in fruit set. We concluded that the effects of birds and bats exclusion on leaf loss and fruit set are modulated by different processes occurring at landscape and local levels. We hypothesized that when local forest cover is high (usually near remnant forest fragments) birds and bats are not only controlling herbivores but may also be reducing mesopredators, while when local forest cover is low (e.g. far from forest fragments), mesopredators do not occur and birds and bats start providing biological pest control by feeding mainly on herbivores. We highlight the importance of employing a multiscale analysis in systems where species with different dispersal abilities are providing an ecosystem service.
146

Sustainable development : why is it not delivering on its promises?

Gonzalez Redin, Julen January 2018 (has links)
At the Rio Conference in 1992, the sustainable development agenda promised a new era for natural resource management, where the wellbeing of human society would be enhanced through a more sustainable use of natural resources. Several decades on, economic growth continues unabated at the expense of natural capital – as evidenced by natural resource depletion, biodiversity loss, climate change and further environmental issues. Why is this happening and what can be done about it? This research examines what socio-economic and governance factors affect sustainability in complex coupled social-ecological systems. Furthermore, it analyses the role of power relations and imbalances between economic and conservation forces with regard to sustainable development. The original contribution to knowledge of this thesis is based on one conceptual and two empirical (Agent-Based) models. These explore, through several case-studies, the potential of different future scenarios in fostering synergies and win-win contexts of ecosystem services and socio-economic indicators. Overall, the research showed the complex and interconnected relationship between the economy and natural systems, and between economic and conservation forces, in coupled social-ecological systems. Addressing complex sustainability issues requires the use of integrative, holistic and interdisciplinary approaches, in addition to considering the particular socio-economic, cultural, political and environmental contexts of the social-ecological system being analysed. The models demonstrated that the current economic system requires an ever-increasing use of natural resources, and that the economy does not protect the natural capital on which it depends. This is based on a disjunction of the economic and conservation elements upon which the sustainable development paradigm is founded. Furthermore, several socio-economic and governance factors appeared to be key for diminishing sustainability in coupled social-ecological systems; namely, the type of economic and production systems, the particular use of monetary debt, technological development, and weak conservation forces (both top-down and bottom-up). However, results also showed alternative scenarios where these same factors could be redirected to enhance social-ecological sustainability. This dual role supports the argument that the current economic system is not inherently (i.e. by definition, per se) unsustainable. Rather, the specific use of economic mechanisms and behaviour of economic entities, as well as their decisions and relationships with the environment, show a tendency to increase unsustainability. Hence, short- and medium-term sustainability can be enhanced by developing mechanisms that start shifting capitalist forces to support environmental conservation; here, the role of Payments for Ecosystem Services will be essential. Enhancing long-term sustainability, however, may require a further paradigm change – where economic and production systems integrate, and fully account for, externalities and the value of natural capital, thus human society is embedded within the wider, and more important, natural environmental system.
147

Mapping and assessment of changes in ecosystem service delivery : a historical perspective on the Tweed catchment, Scotland, UK

Ncube, Sikhululekile January 2016 (has links)
For centuries, river catchments and their constituent habitats have been altered and modified through various human activities to maximise provision of tangible benefits like food and water, while impacting on their capacity to provide other less obvious but equally important benefits for human survival. However, in the last few decades, perceptions on the role of catchments as mere providers of tangible benefits have been changing, as recognition has been given to other human beneficial services like regulation of floods. This recognition has drawn increased interest in both science and policy, towards understanding human-nature relations and how approaches like the ecosystem services concept can inform sustainable management of catchments. Although, the multiple and differently weighted relationships existing between habitats and ecosystem services have been acknowledged, the relationship between spatio-temporal change in habitats and spatio-temporal change in ecosystem services delivery, has not received as much attention in the research literature. In this thesis, it is argued that this is an important omission as spatio-temporal habitat change could have broader consequences for ecosystem services provided by a catchment. On this basis, this study maps and assesses the influence of habitat changes across space and time on ecosystem services delivery at a local catchment scale. Approaches to assessing ecosystem service delivery across landscapes and catchments draw on habitat mapping data for those landscapes or catchments. Such data are in turn used as proxies for estimating different ecosystem services delivered by the landscape or catchment based on their integration with other spatial or non-spatial data. To date this approach has been applied to assess contemporary delivery of different ecosystem services. The basis of the approach taken in this study involved comparing a pre-existing contemporary ecosystem service assessment of two chosen sub catchments of the Tweed catchment in Scotland, with a similar assessment based on a set of older “historic” habitat maps for the mid-20th century period. Derivation of the digital map base for the latter was a major focus of the present study. Aerial photography taken during the Royal Air Force surveys in the 1940s archived in the Royal Commission on Ancient and Historical Monuments of Scotland were obtained and first scanned digitally, arranged into a mosaic of adjacent images and ortho-rectified to remove camera distortion. These photo mosaics were then visually interpreted and, aided with ancillary data, the current (2009) habitat maps were edited and backdated to derive the historic habitat maps for the study catchments. The Spatial Evidence for Natural Capital Evaluation (SENCE) ecosystem services mapping approach was then used to translate generated habitat maps into ecosystem service supply maps. Findings show that the study catchments changed from multifunctional to intensively managed landscapes by 2009, with a higher capacity for supplying provisioning ecosystem services, while their capacity to supply regulating and supporting ecosystem services was reduced. Findings also show that a change in one habitat type results in changes in multiple ecosystem services, while changes in the spatial configuration of habitats reduces areas with high supply capacity for regulating and supporting ecosystem services. This study concludes that ecosystem service delivery is not only affected by changes in gross area of constituent habitats but also by spatial changes in the configuration and distribution of these habitats. In this regard, it is argued that recognising and understanding changes in ecosystem services adds an important strand in catchment management. It is therefore suggested that planning for future ecosystem services in catchment management needs to be informed by historic baselines.
148

Effects of land use on wetland carbon storage and ecosystem services in the tropics : A first estimation investing rural wetlands in central and eastern Uganda

Hedman, Astrid January 2019 (has links)
Wetlands provide important ecosystem services (ES) by storing large amounts of organic carbon (OC) and being of high biological, cultural, and economical value. Uganda is covered by vast wetland areas but has with a booming population rapidly been decreasing due to pressure on lands. The aim of this report was to examine important socio-ecological dynamics of rural wetlands in relation to variations of land use in central and eastern Uganda. This by assessing above- (ABG) and belowground (BG) C stocks, soil pH, and capturing provisioning ES and related impacts on soil and vegetation. The methods involved initial spatial analysis followed by two field campaigns with collection of soil samples, biomass measurements and recordings of provisioning ES, following locally developed standardized methods. Laboratory soil analyses included bulk density, loss on ignition and pH. The results shows that the permanent wetland LUC classes store the most total ecosystem C (273.5 to 356.5 t C ha-1), with the BG pool being the largest. It further brings new insights to the much less studied seasonal wetlands that also proves to be an important C stock (331.1 t C ha-1) as well as providing essential ES. In line with previous research, the total ecosystem C and the provisioning ES of wetlands decreases with changing land use management (farmlands 185 to 209; grasslands 125; woodland 120 to 284 t C ha-1). Further knowledge of socio-ecological dynamics of wetlands is needed, especially in seasonal wetlands, to increase sustainable wetland management. This being urgently needed for many communities in Uganda that are dependent on agroecologically-based economies in close relation to wetland ES and vulnerable to climate variations.
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The Conservation Reserve Program as a Payments for Water Quality Case Study: An Environmental Economic Analysis

January 2019 (has links)
abstract: Payments for ecosystem services (PES) are transactions between landholders and the beneficiaries of the services their land provides. PES schemes are growing worldwide with annual transactions over ten billion dollars (Salzman et al., 2018). Much can be learned from looking at oldest and best funded PES schemes on working agricultural land. Initiated in 1985, the USDA’s Conservation Reserve Program (CRP) is the oldest private conservation PES program in the United States. CRP incentivizes farmers to put their land into conservation through an annual payment. In Iowa, CRP has been a source of extra income and a way for farmers to buffer the fluctuating costs of cash crops, such as corn and soy. The dominance of agriculture in Iowa poses many challenges for water quality. A potential solution to the problem, implemented through CRP, is the use of conservation practices to mitigate the negative effects of agricultural run-off. This dissertation considers three aspects of the problem: 1. the relationship between changes in land cover due to CRP enrollment and changes in water quality, controlling for a range of factors known to have an effect on the filtering role of different land covers; 2. the inter-annual variability in water quality measures and enrollment in different CRP conservation practices to examine the cost-effectiveness of specific conservation practices in mitigating lake sedimentation and eutrophication; 3. discrete choice models to identify what characteristics drive the enrollment by farmers into specific conservation practices. Results indicate that land cover and CRP have different impacts on different indicators of lake water quality. In addition, conservation practices that were cost-effective for one water quality variable tended to be cost-effective for the other water quality variables. Farmers are making decisions to enroll in CRP based on the opportunity cost of the land. Therefore, it is necessary to alter financial incentives to promote productive land being putting into CRP through continuous sign-up. The United States Department of Agriculture (USDA) needs a more effective way to calculate the payment level for practices in order to be competitive with the predicted value of major crops. / Dissertation/Thesis / Doctoral Dissertation Biology 2019
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Understanding perceptions of urban biodiversity and its benefits

Zumhof, Brianna J. 01 May 2019 (has links)
The human population is rapidly urbanizing, creating dramatic changes in local land use and land cover, unprecedented species loss, and a society increasingly disconnected from nature. Nature, specifically biodiversity, has been shown to provide benefits and enhance well-being to humans. Living in an environment with reduced opportunity to interact with or experience biodiversity has increasingly been recognized as both a public health and environmental issue, whereby separation from nature can negatively impact human well-being and how humans value nature, diminishing interest in and understanding of nature and its conservation. Because urban living reduces contact with nature, it is imperative to understand how urban residents perceive and benefit from urban nature to better manage urban biodiversity to both support human well-being and conservation efforts. This study examines how urbanites perceive and benefit from two types of urban nature, trees and birds, by combining surveys of local residents with tree and bird data collected in two Midwestern agricultural cities, Cedar Rapids and Iowa City, Iowa from neighborhoods of varying urban intensity. A residential survey was distributed to these neighborhoods during the summer of 2018 to assess resident perceptions of neighborhood biodiversity and its benefits. In general, residents were not able to assess relative levels of biodiversity compared to other neighborhoods, except in the case of high tree species richness. There was a strong relationship between perceived biodiversity and actual biodiversity, as well as reported knowledge of a given taxon, but only residential perceptions of biodiversity, not actual biodiversity, were strongly related to reported benefits. Respondent perceptions of the influence of trees on their well-being exhibited strong relationships with a person’s connection to trees. Reported influence of birds on well-being was strongly related to a person’s connection to trees, connection to birds, and landscaping practices to support wild species in their yards. Actual bird species richness was significantly negatively related to perceived influence of birds on well-being. Perceived nuisances associated with trees were significantly negatively related to perceived tree species richness, while a person’s connection to trees was strongly positively related to tree nuisances. These results indicate that reported perceptions of the benefits from biodiversity are most heavily influenced by resident perceptions of biodiversity itself and orientation toward nature. This finding also implies that residents benefit from the presence of biodiversity, but that perceived benefits are only related to respondent perceptions of biodiversity, not to actual biodiversity. Further research is necessary to understand why and how this paradox occurs, yet this study provides reason to support efforts to increase knowledge of species as well as provide biodiverse environments that create opportunities for interaction with urban nature. Providing both would strengthen urban resident well-being and support biodiversity and conservation initiatives within cities.

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