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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.
481

Terrestrial Ecosystem Classification in the Rocky Mountains, Northern Utah

Kusbach, Antonin 01 May 2010 (has links)
Currently, there is no comprehensive terrestrial ecosystem classification for the central Rocky Mountains of the United States. A comprehensive classification of terrestrial ecosystems in a mountainous study area in northern Utah was developed incorporating direct gradient analysis, spatial hierarchy theory, the zonal concept, and concepts of diagnostic species and fidelity, together with the biogeoclimatic ecosystem classification approach used in British Columbia, Canada. This classification was derived from vegetation and environmental sampling of both forest and non-forest ecosystems. The SNOwpack TELemetry (SNOTEL) and The National Weather Service (NWS) Cooperative Observer Program (COOP) weather station network were used to approximate climate of 163 sample plots. Within the large environmental diversity of the study area, three levels of ecosystem organization were distinguished: (1) macroclimatic - regional climate; (2) mesoclimatic, accounting for local climate and moisture distribution; and (3) edaphic - soil fertility. These three levels represent, in order, the L+1, L, and L-1 levels in a spatial hierarchy. Based on vegetation physiognomy, climatic data, and taxonomic classification of zonal soils, two vegetation geo-climatic zones were identified at the macroclimatic (L+1) level: (1) montane zone with Rocky Mountain juniper and Douglas-fir; and (2) subalpine zone with Engelmann spruce and subalpine fir as climatic climax species. A vegetation classification was developed by combining vegetation samples (relevés) into meaningful vegetation units. A site classification was developed, based on dominant environmental gradients within the subalpine vegetation geo-climatic zone. Site classes were specified and a site grid was constructed. This site classification was coupled with the vegetation classification. Each plant community was associated with its environmental space within the site grid. This vegetation-site overlay allowed ecosystems to be differentiated environmentally and a structure, combining zonal, vegetation, and site classifications, forms a comprehensive ecosystem classification. Based on assessment of plant communities' environmental demands and site vegetation potential, the comprehensive classification system enables inferences about site history and successional status of ecosystems. This classification is consistent with the recent USDA, Forest Service ECOMAP and Terrestrial Ecological Unit Inventory structure and may serve as a valuable tool not only in vegetation, climatic, or soil studies but also in practical ecosystem management.
482

From trees to soil: microbial and spatial mediation of tree diversity effects on carbon cycling in subtropical Chinese forests

Beugnon, Rémy 09 February 2022 (has links)
The loss of biodiversity is affecting all ecosystems on Earth, one of the greatest threats to biodiversity being climate change. Forests have been highlighted for the potential to mitigate climate change by storing carbon above- and belowground in soils. In this thesis, I studied the effects of tree diversity on carbon cycling in subtropical Chinese forests. I aimed to explore the mechanisms behind tree diversity effects on carbon cycling by focusing on microbial-based processes and the consequences of tree diversity-induced spatial heterogeneity. First, my colleagues and I tested the effects of tree diversity on litterfall spatial patterns and the consequences for litter decomposition and quantified the importance of microbial community in decomposition processes. Second, we explored the effects of tree diversity on relationships between soil microbial facets and soil microbial functions. Third, we tested the effects of tree diversity on soil microbial biomass and carbon concentrations, and their mediation by biotic and abiotic conditions. Finally, we explored the consequences of diversifying forests for re-/afforestation initiatives and plantations to reduce atmospheric carbon levels, and the benefits of diversity for mitigating the effects of climate change on ecosystems and human well-being. We highlighted the positive effects of tree diversity on tree productivity. By increasing the amount and diversity of litterfall, tree diversity increased litter decomposition and subsequently the assimilation of tree products into the forest soils. Our investigation has shown the key role of microbial communities for forests carbon dynamics by carrying out litter decomposition, soil heterotrophic respiration, and soil carbon stabilization. Most notably, tree diversity effects on soil microbial respiration were mainly mediated by soil microbial biomass rather than soil microbial community taxonomic or functional diversity. The effects of tree diversity on microbial biomass were mediated by biotic and abiotic conditions. Taken together, we revealed the importance of considering space to understand biodiversity-ecosystem functioning relationships. Finally, we argued that tree diversity is a promising avenue to maximize the potential of re-/afforestation projects to mitigate increasing atmospheric carbon. Moreover, we highlighted that diversifying forests in re-/afforestation initiatives can help to reduce climate change effects on ecosystems: first, by increasing resistance and resilience to extreme climatic events, and second, by buffering microclimatic conditions in natural and urban areas. My investigation highlighted that tree diversity effects on ecosystem functioning could be explained by both mass and diversity effects on higher trophic levels and their functions. In addition, I showed the key role of tree diversity-induced spatial heterogeneity and the need to consider space and time in further research. Moreover, these results need to be combined with practitioner constraints to enable feasible restoration projects.:Summary table Bibliographic information .................................................................................... I ~ XV Main body ......................................................................................................... 1 ~ 212 Supplementary materials ..................................................................................... i ~ xv Scientific supplementary materials ............................................................. -1- ~ - 154- Table of Contents Table of figures .......................................................................................................... XI Table of scientific supplementary materials ............................................................. XIII Glossary ................................................................................................................... XV Introduction ................................................................................................................. 3 Chapter I - Tree diversity effects on litter decomposition are mediated by litterfall and microbial processes .................................................................................................. 35 Transition I - II ........................................................................................................... 67 Chapter II - Tree diversity and soil chemical properties drive the linkages between soil microbial community and ecosystem functioning................................................ 71 Transition II - III ....................................................................................................... 107 Chapter III - Abiotic and biotic drivers of scale-dependent tree trait effects on soil microbial biomass and soil carbon concentration ................................................... 111 Transition III - IV ..................................................................................................... 155 Chapter IV – Diverse forests are cool: promoting diverse forests to mitigate carbon emissions and climate change ............................................................................... 159 General discussion ................................................................................................. 173 Abstract .................................................................................................................. 195 General acknowledgments ..................................................................................... 209 Supplementary materials ..............................................................................................i
483

Initiating an Internet of Things Ecosystem inPractice : A qualitative study carried out at IBM Sweden / Att inleda ett Internet of Things Ekosystem i praktiken

Astner, Josephine January 2018 (has links)
The Internet of Things (IoT) concludes a network of physical objects equipped withdigital technologies to interact with people and other objects. IoT brings challenges,one way for organisations to address these challenges is by business ecosystems accordingto the analogy of natures ecosystem. This study defines an IoT oriented businessecosystem as an IoT ecosystem, because of the definitions used in the market varies.The purpose of this study was to investigate the critical factors for a working IoTecosystem, as well as propose how these factors can be applied in practice, since thisis absent in the market. A customized research design was conducted for this studyto manage the 17 semi-structured interviews at IBM. The interviews were divided initerations with di↵erent themes, where the result of each iteration was the base forthe decision of the next iteration theme. The result of this study reflected severalcritical perspectives of how to create an IoT ecosystem with partnership, end-userand scalability were recurrent. The conclusion of this were six critical factors of howan organisation can initiate an IoT ecosystem anchored with a product, as well as atool of how to apply these factors in practice. / Internet of Things (IoT) är ett koncept som innebär att fysiska objekt är utrustademed digital teknologi för att kunna vara uppkopplade mot internet, vilket möjliggörinteraktion med både människor och andra uppkopplade objekt. Med IoT följermånga utmaningar, ett sätt för organisationer att adressera några av dem är genoma affärsekosystem enligt analogi med naturens ekosystem. Det finns olika definitioner avkonceptet IoT ekosystem på marknaden som förklarar innebörden, därför definieraskonceptet i denna studie som ett affärsekosystem med utformning för IoT. Syftet med studien var att undersöka de kritiska faktorerna för ett fungerande IoT ekosystem samt att föreslå hur dessa faktorer kan användas i praktiken, då dettasaknas på marknaden. Forskningsmetoden i studien anpassades efter dess syfte, medinsamling av data från 17 stycken semistrukturerade intervjuer på IBM. Intervjuernavar indelade i iterationer med olika teman där resultat av varje iteration låg tillgrund för val av nästa iterationstema. Resultatet av studien på visade efter fyraiterationer, flera kritiska perspektiv för att skapa ett IoT ekosystem där partnerskap, slutanvändare och skalbarhet var återkommande. Slutsatsen blev sex kritiska faktorer för hur en organisation kan inleda ett IoT ekosystem kring en produkt, samt ettverktyg för hur dessa faktorer kan appliceras i en organisation i praktiken.
484

[en] INNOVATION OF SUSTAINABLE BUSINESS MODELS IN ECOSYSTEMS: THE IMPORTANCE OF ORCHESTRATION / [pt] INOVAÇÃO DE MODELOS DE NEGÓCIOS SUSTENTÁVEIS EM ECOSSISTEMAS: A IMPORTÂNCIA DA ORQUESTRAÇÃO

WILLIAM DE ASSIS FONSECA DOS SANTOS 26 September 2024 (has links)
[pt] A criação e o gerenciamento de novos de modelos de negócios exige, cada vez mais, estratégias atreladas a indicadores e a resultados sustentáveis. Na busca pela geração de valor de longo-prazo nestes modelos - calcada nas dimensões sociais, ambientais e econômicas -, e de modo a garantir também maiores níveis de competitividade para as empresas, pesquisadores e praticantes têm voltado esforços para alcançarem estas metas por meio do uso constante de inovação. Inovações que possibilitam altos índices de sustentabilidade encontram-se, sobretudo, na integração de organizações em ecossistemas de inovação. Consequência desta união entre inovação e sustentabilidade gera o que se convenciona chamar de inovações em modelos de negócios sustentáveis. O surgimento de tais modelos levanta um interessante debate: os fatores que compõem a orquestração de ecossistemas - conhecidos como capacidade absortiva, apropriabilidade da inovação e estabilidade da rede (que aglutina as firmas) - são capazes de moderar positivamente a relação entre a integração de empresas em ecossistemas e as inovações em modelos de negócios sustentáveis? Por meio do referencial teórico e de dados primários de 302 empresas de manufatura brasileiras analisados por meio de modelagem de equações estruturais, a presente dissertação reúne subsídios para responder a este questionamento. Como resultado da investigação realizada, é possível perceber a interferência positiva da capacidade absortiva e da apropriabilidade da inovação no vínculo existente entre a integração de firmas em ecossistemas e um maior grau de inovação em modelos de negócios sustentáveis. / [en] The creation and management of new businesses demands, more and more, strategies connected to sustainable indicators and results. In the search to generate long-term value in these models - based on social, environmental and economic dimensions -, and in order to also guarantee greater competitive levels for businesses, researchers and practitioners have been making efforts to reaching these goals through the constant use of innovation. Innovation that enables high standards of sustainability are located, specially, in the incorporation of organizations of business ecosystems. As a consequence of this union between innovation and sustainability is the generation of what is conventionally called innovation in sustainable business models. The advent of such models rises an interesting debate: are the factors that compose the ecosystems orquestration - known as absorptive capacity, innovation appropriability and network stability (which binds the firms) - capable of positively tempering the relationship between the integration of businesses in ecosystems and the innovation in sustainable business models? Through the theoretical reference and the primary data of 302 companies of the Brazilian manufacturing sector analyzed by the modeling of structural equations, this dissertation combines subsidies to answer this question. As a result of the investigation performed, it is possible to notice the positive interference of the absorptive capacity and the innovation appropriability on the existing bind between the integration of firms in ecosystems and a greater level of innovation in sustainable business models.
485

Understanding the Concept and Practice of Ecosystem Approaches to Health in the Context of Public Health

Nguyen, Vi 02 May 2011 (has links)
A scoping study of the published literature was used to describe the concept and practice of ecosystem approaches to health (ecohealth) in the context of public health. Analysis of commentaries identified 24 themes, expressed in a mind map showing interconnections between themes, with a table of explanations. Most (27 of 29) primary research articles did not explicitly explain how ecohealth was applied in their research, suggesting a need for some standardization in reporting ecohealth. Additionally, a case study approach was undertaken to identify enablers and impediments of ecohealth and how concepts were integrated into a research project of health and environmental sanitation in Vietnam. The project’s conceptual framework was aligned with ecohealth concepts, but in practice, a variety of challenges were identified. In future, ecohealth research teams should include a self-investigation of their ecohealth process to facilitate a comparison of theory-to-practice; this may serve as a best practice for ecohealth. / Public Health Agency of Canada (PHAC), Community of Practice in Ecosystem Approaches to Health - Canada (CoPEH-Can)
486

Valuing ecological services and community design : implications for the private market and local government

Hegg, Daniel Alexander 25 August 2009 (has links)
Presently, conventional development does not adequately incorporate functional ecosystems into development design. Largely due to the intangible nature of most ecosystem services, functional ecosystems have not been directly identified as valuable and are, therefore, often ignored in economic decision frameworks. This has resulted in the degradation and loss of functional ecosystems and ecosystem services as the value and the associated costs of lost ecosystem services are not accounted for. The valuation of ecosystem services is a means by which ecological costs and values can be adequately represented in urban planning and decision-making processes. However, using current valuation methods, ecosystems are continuously being valued for their aggregated ecosystem service values and not for the value of their ability to resist/recover from disturbances and continue proving goods and services over time. The Swan Lake watershed case study was utilized to show that the estimated ecosystem service values are not risk adjusted to reflect the functional condition of an ecosystem. Specifically, based upon the current valuation estimates alone and without reference to the functional condition, the estimated ecosystem service values for the Swan Lake study suggest that the watershed is in a good (proper) functional condition, when in-fact, the overall health of the watershed is in a poor condition of health and its resilience to disturbance is low. Furthermore, the estimated values do not reflect the loss of ecosystem services due to past urbanization and agricultural activities. Because the estimated values do not provide the critical information decision makers require, the valuation of the functional condition of ecosystems is recommended. Due to the complexity involved in valuing the functional condition of an ecosystem, the integration of ecosystem valuation methods and ecosystem evaluation assessments is proposed and explored. In the context of post-urban planning and development, the proposed approach has immediate application as it would provide effective financial arguments for the preservation and restoration of ecosystems as well as facilitate more informed decisions in managing existing urban ecosystems for their function rather than ecosystem services. In a pre-development application, there exists a opportunity wherein an ecosystem’s functional condition could be valued as part of an integrated development design and planning process (IDP). The British Pacific Properties (BPP) Rodgers Creek development is used as a case study to describe how the proposed approach could be incorporated into the integrated design and planning (IDP) process. By clarifying the ecological tradeoffs between various land-use/development scenarios using a sieve analysis, the proposed approach could help a design team render more informed judgments regarding the functional condition of ecosystems and the value of the ecosystem services. The proposed approach also contributes to a much needed business case, which demonstrates that when urban developments are planned using an IDP process, where the landscape informs the design, there can be greater financial reward to the developer, community and municipality
487

A comparison of ecosystem health and services provided by subtropical thicket in and around the Bathurst commonage

Stickler, Meredith Mercedes January 2010 (has links)
Municipal commonage in South Africa offers previously disadvantaged, landless residents access to both direct ecosystem goods and services (EGS) that provide additional income options and indirect social and cultural services. Given that EGS production is a function of ecosystem health, it is imperative that commonage land be managed to maximize current local benefit streams while ensuring future options through the maintenance of natural ecosystem functions. The payments for ecosystem services (PES) model potentially offers an opportunity for contributing to local economic development while providing fiscal incentives for environmentally sustainable natural resource management. PES depends on the demonstration of quantifiable changes in EGS delivery due to improvement in or maintenance of high ecosystem health that are a verifiable result of modifications in management behavior. This thesis therefore compared spatial variations in (i) ecosystem health and (ii) nine direct and indirect EGS values derived from natural resources on the Bathurst municipal commonage and neighboring Waters Meeting Nature Reserve (NR) to explore how different land use intensities affect ecosystem health and the resulting provision of EGS. The results indicate that the total economic value of annually produced EGS on the study site is nearly R 9.8 million (US$ 1.2 million), with a standing stock of natural capital worth some R 28 million (US$ 3.4 million). Nearly 45% of the total annual production is attributed to Waters Meeting NR, with roughly 34% from the low use zone of the commonage and the remaining 22% from the high use zone. Of the total annual production value on the study site, roughly 59% is derived from indirect (non-consumptive) uses of wildlife for the study site as a whole, though this proportion varies from 25% in the high use zone of the commonage to 94% on Waters Meeting NR. The two largest annual production values on the study site derive from ecotourism (R 3.5 million, US$ 0.4 million) and livestock production (R 2.6 million, US$ 0.3 million), suggesting that while increased production of indirect EGS could generate significant additional revenues, especially on Waters Meeting NR and in the low use zone of the commonage, direct (consumptive) EGS will likely remain an important component of land use on the commonage. A PES project to support the adoption of silvo-pastoral practices could provide positive incentives for improved land use practices on the commonage and potentially be financed by conservation-friendly residents of the Kowie River catchment and/or increased ecotourism revenues from Waters Meeting NR. Allowing carefully designed and monitored local access to natural resources within Waters Meeting NR could also reduce pressure on commonage resources. Together, these approaches could lead to a more sustainable subtropical thicket landscape and ensure that critical natural resources remain available to support local livelihoods in the long-term.
488

[en] ANALYSIS AND SPATIAL DISTRIBUTION OF ECOSYSTEM SERVICES IN THE CITY OF RIO DE JANEIRO / [pt] ANÁLISE E DISTRIBUIÇÃO ESPACIAL DOS SERVIÇOS ECOSSISTÊMICOS DA CIDADE DO RIO DE JANEIRO

CARINE SZNECZUK DE LACERDA 14 March 2022 (has links)
[pt] Os serviços ecossistêmicos (SE) são os benefícios que a sociedade obtém dos ecossistemas e que são fundamentais para o seu bem-estar. Para que este framework possa ser utilizado na tomada de decisão, o primeiro passo é o seu mapeamento. Esta dissertação mapeou qualitativamente o potencial de provisão de oito SE para a cidade do Rio de Janeiro – controle de inundações, manutenção da qualidade do ar, regulação climática, mitigação de tempestades e eventos extremos, beleza cênica, religião e espiritualidade, recreação e turismo, e saúde física e mental. O mapeamento foi realizado através de reclassificação de dados de uso e cobertura do solo, definição de SE prioritários e entrevistas com especialistas. O estudo constatou que houve aumento do percentual de área urbana e diminuição da provisão de cinco SE em todas as regiões da cidade. O estudo também mapeou a oferta e demanda de serviços ecossistêmicos culturais (SEC), com o objetivo de identificar a relação dos habitantes da cidade com os ecossistemas locais a partir da aplicação de questionário eletrônico. Verificou-se que os habitantes da Zona Sul e Zona Oeste frequentam, preferencialmente, áreas próximas aos bairros onde moram e, prioritariamente, praias. A Zona Norte é a região com maior percentual de área urbana (82 por cento) e menor oferta de áreas naturais. Apesar da cidade contar com uma enorme diversidade de ecossistemas, estes não estão distribuídos de maneira equânime no território e há diferenças significativas tanto na oferta de áreas naturais, quanto nas características socioeconômicas quando comparamos as cinco grandes Áreas de Planejamento municipais. / [en] Ecosystem services (ES) are the benefits that society obtains from ecosystems and are fundamental to human well-being. For this framework to be used in decision making, the first step is mapping ES. This study mapped the provision of eight ES for the city of Rio de Janeiro - flood control, air quality maintenance, climate regulation, mitigation of storms and extreme events, scenic beauty, religion and spirituality, recreation and tourism, and physical and mental health. Mapping was accomplished through reclassification of land use and land cover data, definition of priority ESs, and interviews with experts. The study found that there was an increase in the percentage of urban area and a decrease in the provision of five SEs in all regions of the city. The study also mapped the supply and demand of cultural ecosystem services (CES), to identifying the relationship of the city s inhabitants with local ecosystems through the application of an electronic questionnaire. It was found that the inhabitants of the South Zone and West Zone preferably frequent areas close to the neighborhoods and, as a priority, the beaches. The North Zone is the region with the highest percentage of urban area (82 percent) and the lowest offer of natural areas. Although the city has an enormous diversity of ecosystems, these are not equally distributed in the territory and there are significant differences both in the supply of natural areas and in socioeconomic characteristics when we compare the five large municipal Planning Areas.
489

Opportunities and challenges for mainstreaming ecosystem services in decision making

Sitas, Nadia 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Ecosystem service research has grown significantly in recent years, highlighting links between ecosystem services and human well-being. Few studies are however, geared towards providing user-friendly, user-useful and user-relevant information suitable for implementing effective local management of areas that deliver ecosystem services, resulting in a gap between ecosystem service research and management. In response to this challenge, it has been argued that in order to safeguard the benefit flows provided by ecosystems, the concept of ecosystem services should be mainstreamed into land-use (and water-use) planning and management processes. As the conservation of ecosystem services is ultimately a social process operating in a social context, understanding the complexity of the research-management interface demands input from a range of stakeholders. Thus, mainstreaming the environment into decision making requires multi-stakeholder engagement processes that facilitate the co-production and exchange of knowledge. Accordingly, through the use of a transdisciplinary, mixed method approach, this dissertation contributes to a better understanding of some of the opportunities and challenges for mainstreaming ecosystem services in development planning at a local level, using a case study in the Eden District (Eden) of South Africa. Through an extensive stakeholder engagement process which explored what the information needs, responsibilities and capacities of decision makers in Eden are, both opportunities that facilitate the integration of ecosystem service information in decision making, and challenges impeding integration, have been identified. This research found that despite a history of ecosystem service research in Eden, there has been limited integration of the concept of ecosystem services into decision-making processes driving development. Insufficient capacity, limited resources, minimal proactive planning, a weak regulatory environment, entrenched disciplinary thinking and insufficient communication amongst diverse stakeholders on the benefits of using an ecosystem-based approach remain as challenges for the mainstreaming of ecosystem services in decision making. However, strategic opportunities for mainstreaming ecosystem services into decisions regarding current and future development trajectories were also found. It was found that the development, and nurturing of transdisciplinary learning networks that are problem driven, and action oriented, using a communities of practice model of engagement, can facilitate legitimate knowledge exchange processes. In this regard, the role of individual and institutional knowledge brokers was found to be critical. It was also found that the concept of risk was useful as a mainstreaming tool in bridging the gaps between different disciplines, and between science, policy and practice. A frame of risk enabled different disciplinary and knowledge communities to participate in joint activities and discussions during which information was co-produced and exchanged. Through this work, new relationships were built that facilitated both learning and action with regards to the importance of ecosystem services for mitigating risk. / AFRIKAANSE OPSOMMING: Ekosisteemdiens-navorsing het aansienlik gegroei in die afgelope jare, met ‘n klem op die verband tussen ekosisteemdienste en menslike welsyn. Min ondersoeke is egter gerig op die verskaffing van gebruikersvriendelike, -nuttige en -relevante inligting wat geskik is vir die implementering van doeltreffende plaaslike bestuur van die gebiede wat ekosisteemdienste lewer, en dit lei tot 'n gaping tussen ekosisteemdiens-navorsing en -bestuur. In reaksie op hierdie uitdaging word aangevoer dat ekosisteemdienste gehoofstroom moet word in prosesses ter beplanning en bestuur van grond- en watergebruik, ten einde die voordele wat deur ekosisteme gebied word, te beskerm. Omdat die behoud van ekosisteemdienste per slot van rekening `n sosiale proses is wat in `n sosiale konteks in werking is, word insette van 'n verskeidenheid van belanghebbendes vereis, om die ingewikkelde aard van die koppelvlak tussen navorsing en bestuur te verstaan. Dus, om die omgewing in besluitneming te hoofstroom, vereis prosesse van betrokkenheid van veelvuldige belanghebbendes, wat die medevervaardiging en uitruil van kennis fasiliteer. Gevolglik, deur die toepassing van `n transdissiplinêre, gemengde metode benadering in `n gevallestudie in die Eden Distrik (Eden) van Suid-Afrika, dra hierdie verhandeling by tot `n beter begrip van sommige van die geleenthede en uitdagings verbonde aan die hoofstroming van ekosisteemdienste in ontwikkelingsbeplanning op 'n plaaslike vlak. Deur `n uitvoerige proses van deelname met belanghebbendes is inligting benodig deur besluitnemers in Eden, sowel as hul verantwoordelikhede en vermoëns, verken, en sodoende is beide die geleenthede wat die integrasie van ekosisteemdiens-inligting in besluiteming fasiliteer, en uitdagings wat integrasie belemmer, geïdentifiseer. Hierdie navorsing het bevind dat, ten spyte van `n geskiedenis van ekosisteemdiens-navorsing in Eden, is daar beperkte integrasie van die konsep van ekosisteemdiens in besluitnemingsprosesse wat ontwikkeling dryf. Onvoldoende kapasiteit, beperkte hulpbronne, minimale proaktiewe beplanning, 'n swak reguleringsomgewing, verskanste dissiplinêre denkwyses en onvoldoende kommunikasie tussen uiteenlopende belanghebbendes oor die voordele verbonde aan die gebruik van 'n ekosisteembenadering, bly uitdagings vir die hoofstroming van ekosisteemdienste in besluitneming. Maar strategiese geleenthede vir die hoofstroming van ekosisteemdienste in besluitneming in verband met huidige en toekomstige ontwikkelingsbane is ook aangetref. Daar is bevind dat, deur transdissiplinêre leernetwerke wat probleemgedrewe en aksie-georiënteerd is, te ontwikkel en koester met behulp van 'n praktykgemeenskappemodel van betrokkenheid, legitieme kennisuitruilingsprosesse gefasiliteer kan word. In hierdie verband is die rol van individuele en institusionele kennismakelaars as krities bevind. Daar is ook bevind dat die konsep van risiko nuttig is as 'n hoofstromings-instrument in die oorbrugging van die gaping tussen die verskillende dissiplines, en tussen wetenskap, beleid en praktyk. `n Raamwerk van risiko het verskillende dissiplinêre en kennisgemeenskappe in staat gestel om deel te neem aan gesamentlike aktiwiteite en besprekings, waartydens inligting saam geproduseer en uitgeruil is. Deur hierdie werk is nuwe verhoudings gevestig, wat beide leer en optrede rakende die belang van ekosisteemdienste vir risikotempering gefasiliteer het.
490

Experimental biodiversity enrichment in an oil-palm plantation

Gérard, Anne 15 November 2016 (has links)
Die großflächige Umwandlung von tropischen Wäldern hat zu dramatischen Verlusten von Biodiversität und assoziierten Ökosystemdienstleistungen und –funktionen geführt. Indonesien ist ein besonders schwerwiegendes Beispiel für den Verlust von Waldflächen und Biodiversität. Landumnutzungen, in starkem Maße durch den Anbau von Ölpalmen vorangetrieben, stellen eine erhebliche Bedrohung für die außergewöhnlich hohe Biodiversität des Landes dar. Landwirtschaftssysteme, wie Agroforstsysteme, können hingegen genutzt werden, um die Biodiversität und Ökosystemfunktionen in von Ölpalmen dominierten Landschaften zu erhöhen. In Regionen, in denen Ölpalmplantagen bereits die Landschaft dominieren, kann diese Erhöhung nur durch systematische Renaturierung erfolgen. Die zugrunde liegenden ökologischen und soziökonomischen Prozesse und damit verbundene Beschränkungen und Kompromisse von Renaturierungsmaßnahmen in von Ölpalmen dominierten Landschaften sind jedoch weitgehend unbekannt. Um diese Wissenslücke zu schließen, habe ich mit Kollegen aus Deutschland und Indonesien ein Langzeitexperiment zur Erhöhung der Biodiversität aufgebaut. Wir haben experimentell Bäume in Form von „Inseln“ in eine konventionelle Ölpalmplantage gepflanzt und hierbei systematisch die Flächengröße, das Diversitätslevel und die Artzusammensetzung variiert. Wir haben hierfür sechs multifunktionale heimische Baumarten ausgewählt. Auf der Fläche der Bauminseln haben wir einen Teil der Ölpalmen gefällt, um die Lichtverfügbarkeit für die gepflanzten Bäume durch eine reduzierte Ölpalmdichte zu erhöhen. In dieser Doktorarbeit stelle ich den Aufbau des Experiments vor und gebe einen breiten Einblick in anfängliche Auswirkungen des Experiments, indem ich ökologische Aspekte in Betracht ziehe, sowie Veränderungen hinsichtlich des Ernteertrags. Da die Zeit kurz nach der Pflanzung ein Nadelöhr für die Langzeitetablierung der Bäume darstellt, ist sie sehr kritisch, um die erwünschten Renaturierungserfolge in der Zukunft zu erzielen. Des Weiteren kann die Anfangszeit auch aus der Sicht der Landwirte eine entscheidende Hürde darstellen, da der Nutzen der Bauminseln erst lange Zeit nach ihrer Pflanzung entsteht. Zuerst beschreibe ich Umweltvariablen und biotische Charakteristika der den experimentellen Flächen assoziierten Vegetation, Invertebraten und Vögel vor der Errichtung des Experiments, sowie anfängliche Auswirkungen des Experiments auf die Fauna. Ein Jahr nach der Errichtung des Experiments hatten die Baumpflanzungen einen insgesamt positiven Effekt auf die Artengemeinschaften von Vögeln und Invertebraten in der Plantage. Die Größe der Bauminseln wirkte sich lediglich auf die Diversität und Abundanz von Invertebraten positiv aus, die somit auf kleinskalige Veränderungen reagierten. Ausgehend von diesen Ergebnissen erwarte ich einen weiteren Anstieg der Biodiversität und Ökosystemfunktionen in der Zukunft. Danach berichte ich über den Anwuchserfolg der Bäume und ermittle die wichtigsten Determinanten für den Wuchs und das Überleben der Bäume. Insgesamt sind die Bäume gut angewachsen, jedoch gab es große Unterschiede zwischen den Baumarten hinsichtlich relativer Höhenwachstums-, Dickenwachstums- sowie Überlebensraten. Arten mit hohen Wachstumsraten wiesen vorwiegend auch hohe Überlebensraten auf. Auf Versuchsflächenebene hatten Standortbedingungen, Flächengröße und Diversitätslevel der gepflanzten Bäume lediglich einen geringen Einfluss auf das mittlere Baumwachstum und die Überlebensrate. Auf Individuenebene habe ich signifikante Nachbarschaftseffekte festgestellt. Hohe benachbarte Bäume und die Distanz zu verbleibenden Ölpalmen begünstigten die Entwicklung der Bäume. Noch ist es zu früh zu entscheiden, welche der Baumarten sich generell am besten eignen, um Renaturierungsziele zu erreichen. Unterschiede in der anfänglichen Entwicklung liefern jedoch wichtige Informationen für eine zukünftige Bewertung der Arten. Zuletzt präsentiere ich Auswirkungen des Experiments auf den Ölpalmertrag. Nach zwei Jahren waren die Erträge pro Ölpalmindividuum erhöht, sowohl auf als auch direkt neben den Versuchsflächen. Die geschätzten Ertragsänderungen für die verschiedenen Flächengrößen unter Einbezug von Ernteverlusten durch gefällte Ölpalmen sowie Effekte auf benachbarte Ölpalmen deuten darauf hin, dass die erhöhten Ernteerträge insbesondere in großen Bauminseln mindestens das Fällen von Ölpalmen kompensiert haben. Diese Ergebnisse, die in der frühen Phase der Bauminseletablierung erzielt wurden, sind vielversprechend für die Erarbeitung nachhaltiger Managementoptionen für Ölpalmplantagen, die ökologische und ökonomische Funktionen in Einklang bringen. Die anfänglichen Auswirkungen waren stärker und insbesondere aus ökonomischer Perspektive profitabler als ich erwartet habe. Die Nachbarschaftseffekte und die Auswirkungen der experimentell veränderten Variablen waren bislang jedoch überwiegend schwach. Ich erwarte, dass diese Auswirkungen mit der Zeit stärker ausgeprägt sein werden. Durch Erkenntnisse, die aus zukünftigen Langzeitbeobachtungen des Experiments, das ich in dieser Doktorarbeit vorstelle, gewonnen werden, können Wissenslücken geschlossen werden. Somit kann die Ausarbeitung von Managementrichlinien für von Ölpalmen dominierten Landschaften ermöglicht werden, die sowohl ökologisch verbessert als auch ökonomisch lohnenswert sind. Diese Doktorarbeit stellt einen wesentlichen Beitrag zur generellen Beurteilung des Experiments dar, wodurch darüber hinaus auch neue Erkenntnisse für die Renaturierungswissenschaft gewonnen werden können.

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