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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.
311

Uticaj klimatskih promena na vezivanje ugljenika, rast i biodiverzitet bukovih šuma u Srbiji / The impact of climate change on carbon sequestration, growth and biodiversity of European beech forests in Serbia

Stojanović Dejan 30 June 2014 (has links)
<p>Prognoze Međuvladinog panela o klimatskim promenama govore da će&nbsp;prostor Jugoistočne Evrope biti&nbsp; pod snažnim uticajem izmenjenih klimatskih&nbsp;uslova u 21. veku. Očekuje se da će leta biti toplija i suvlja sa vi&scaron;e&nbsp;ekstremnih događaja i temperaturama koje mogu u proseku porasti i za čak&nbsp;3,8&deg;C, &scaron;to predstavlja veliki izazov za &scaron;umarstvo. Da bi se odgovorilo na taj&nbsp;izazov neophodno je načiniti i sprovesti adekvatne mere adaptacije, &scaron;to bi&nbsp;značilo prilagođavanje mera gazdovanja &scaron;umama novonastlim ekolo&scaron;kim&nbsp;uslovima. Jedan od značajnih alata u tom prilagođavanju predstavljaju&nbsp;različiti &nbsp;modelarski pristupi. U&nbsp; ovoj disertaciji su upotrebljene&nbsp;najsavremenije metode modeliranja uticaja klimatskih promena na &scaron;ume.&nbsp;Radi se o pionirskom istraživanje koje je prvo takve vrste u regionu. Dva&nbsp;različita metodska pristupa, vezanih za distribuciju, rast, adaptivno i&nbsp;multifunkcionalno gazdovanja bukovim &scaron;umama u Srbiji u klimatskim&nbsp;uslovima 21. veka su uputila na nekoliko najbitnijih rezultata i zaključaka. &nbsp;Izmenjeni klimatski uslovi će imati uticaj na rast i distribuciju bukovih &scaron;uma&nbsp;u 21. veku na osnovu simulacija sa 4C modelom i predikcija pomoću&nbsp;Elenbergovog koeficijenta. Na &nbsp;kraju simuliranog perioda 2001-2030 pomoću&nbsp;4C modela zabeležene su &nbsp;veće zapremine za devet sastojina&nbsp;monodominantnih bukovih &scaron;uma u odnosu na referentni period 1961-1990,&nbsp;dok su zapremine na kraju perioda 2071-2100 po pravilu bile veće ili &nbsp;slične&nbsp;referentnom period. Simulacije u period 2001-2030 su proseku imale najveće&nbsp;godi&scaron;nje priraste i najvi&scaron;e mrtvog drveta, a one u period 1961-1990 &nbsp;najmanje.&nbsp;Najbolje rezultate za vezivanje ugljenika i očuvanje biodiverziteta je pokazao&nbsp;scenario gazdovanja u kojem nije bilo intervencija. Suprotno tome, &nbsp;najvi&scaron;e prinosa drveta je zabeleženo u scenarijima sa najintenzivnijim&nbsp;intervencijama. U adaptivnom multifunkcionalnom gazdovanju bukovim&nbsp;&scaron;umama za scenarija preferencija koje su kreirale tri grupe zainteresovanih&nbsp;strana (Uprava za &scaron;ume, sektor za&scaron;tite prirode i JP &bdquo;Srbija&scaron;ume&ldquo;) pokazalo se&nbsp;da gazdovanje koje podrazumeva če&scaron;će zahvate (pet godina između seča)&nbsp;daje bolje rezultate u odnosu scenarija koji podrazumevaju desetogodi&scaron;nje&nbsp;intervale. Scenariji gazdovanja u kojima su posečena visoka stabla su&nbsp;pokazale bolje rezultate u multifunkcionalnom gazdovanju u odnosu na&nbsp;scenarija gde su sečena niža stabla u istom zapreminskom odnosu za sva&nbsp;<span style="font-size: 12px;">scenarija preferencija zainteresovanih strana. Elenbergov koeficijent je&nbsp;</span><span style="font-size: 12px;">pokazao dobru prediktivnu sposobnost za određivanje donje granice&nbsp;</span><span style="font-size: 12px;">distribucije bukovih &scaron;uma u &nbsp;Srbiji. Do kraja 21. veka okvirno 90% dana&scaron;njih&nbsp;</span><span style="font-size: 12px;">bukovih &scaron;uma će se naći izvan bioklimatske ekolo&scaron;ke ni&scaron;e u kojoj su bili u&nbsp;</span><span style="font-size: 12px;">20. veku, dok će se 50% naći u zoni u kojoj je &nbsp;zabeležen njen masovni&nbsp;</span><span style="font-size: 12px;">mortalitet u Mađarskoj. Izračunate granice EQ su bile ne&scaron;to niže od dobijenih&nbsp;</span><span style="font-size: 12px;">u sličnim studijama u region &scaron;to implicira striktan regionalni i lokalni pristup&nbsp;</span><span style="font-size: 12px;">problem. Poređenje rezultata simulacija sa 4C modelom i EQ za posmatranih&nbsp;</span><span style="font-size: 12px;">devet sastojina je pokazalo različite trendove vezano za rast (distribuciju)&nbsp;</span><span style="font-size: 12px;">bukovih &scaron;uma u Srbiji do kraja 21. veka. 4C model je predvideo pobolj&scaron;anje&nbsp;</span><span style="font-size: 12px;">uslova, dok je EQ predvideo pogor&scaron;anje uslova. Iz tog razloga potrebna su&nbsp;</span><span style="font-size: 12px;">dalja kontinuirana dugoročna istraživanja bukovih &scaron;uma kako bi smo dobili&nbsp;</span><span style="font-size: 12px;">pouzdaniju osnovu za procenu budućeg rasprostranjenja, rasta i planiranja&nbsp;</span><span style="font-size: 12px;">gazdovanja ovim &scaron;umama u budućnosti.</span></p> / <p>Predictions of the Intergovernmental Panel on Climate Change suggest that&nbsp;the region of Southeast Europe will be strongly influenced by the altered&nbsp;climate conditions in 21 century. It is expected that the summers will be&nbsp;hotter and drier with more extreme events and temperatures that can rise on&nbsp;average as much as 3.8 &deg;C. That is a big challenge for forestry. To respond&nbsp;to this challenge it is necessary to make and implement appropriate&nbsp;adaptation measures which would mean adapting forest management&nbsp;practice to changed environmental conditions. Different models are one of&nbsp;the important tools which can be used in this purpose. In this dissertation&nbsp;state-of-the art methods for calculating the impact of climate change on&nbsp;forests have been applied. This is a pioneering work and the first of its kind&nbsp;in the region. Two different methodological approaches, related to the&nbsp;distribution, growth, adaptive and multifunctional management of&nbsp;European beech forests in Serbia has been performed and provided&nbsp;following results and conclusions. Changed climatic conditions will have&nbsp;<br />an impact on the growth and distribution of beech forests in 21st century&nbsp;based on simulations with the 4C model and predictions of Ellenberg&rsquo;s&nbsp;climate quotient (EQ). At the end of the simulated period 2001-2030 higher&nbsp;volumes were recorded for the nine beech stands in comparison to the&nbsp;reference period 1961 to 1990, while the volume at the end of the period&nbsp;2071-2100 were higher or similar to the reference period. Simulations in&nbsp;the period 2001-2030&nbsp; have had the greatest average annual increment and&nbsp;the biggest amount of dead wood. The best results for carbon sequestration&nbsp;and biodiversity were provided by management scenario in which there&nbsp;were no management measures. In contrast, the highest yield&nbsp; of timber is&nbsp;recorded in the scenarios with the most intensive management measures.&nbsp;The adaptive multifunctional &nbsp;management of beech forests including three&nbsp;<span style="font-size: 12px;">scenarios of preferences&rsquo; (Forest Directorate , Nature Protection Sector and&nbsp;</span><span style="font-size: 12px;">Public Enterprise &quot;Srbija&scaron;ume&quot; ) suggested that management measures that&nbsp;</span><span style="font-size: 12px;">involved more frequent interventions (five years between felling) gives</span><span style="font-size: 12px;">better results than scenario which include a ten-year periods. Scenarios in&nbsp;</span><span style="font-size: 12px;">which higher trees are cut provide better results than scenario where the&nbsp;</span><span style="font-size: 12px;">lower trees are cut. EQ showed good predictive capability for determining&nbsp;</span><span style="font-size: 12px;">the lower (xeric) limit of the distribution of beech forests in Serbia. By the&nbsp;</span><span style="font-size: 12px;">end of 21st century, approximately 90 % of today&#39;s beech forests will be&nbsp;</span><span style="font-size: 12px;">found outside the bioclimatic niches in which they were in the 20th century,&nbsp;</span><span style="font-size: 12px;">while the 50 % of them will be in the zone in which their mass mortality is&nbsp;</span><span style="font-size: 12px;">observed in Hungary. Calculated EQ beech threshold distribution for Serbia&nbsp;</span><span style="font-size: 12px;">were slightly lower than in similar studies in the region (Hungary) , which&nbsp;</span><span style="font-size: 12px;">implies strict regional and local approach to the problem. Comparison of&nbsp;</span><span style="font-size: 12px;">simulated results with the 4C model and EQ for nine stands showed </span><span style="font-size: 12px;">different trends related to growth (distribution) of beech forests in Serbia by&nbsp;</span><span style="font-size: 12px;">the end of 21st century. 4C model predicted improvement of environmental </span><span style="font-size: 12px;">conditions, while the EQ predicted their worsening. For this reason,&nbsp;</span><span style="font-size: 12px;">continuing long-term studies of beech forests are needed in order to get a&nbsp;</span><span style="font-size: 12px;">more reliable basis for estimating future distribution, growth and planning&nbsp;</span><span style="font-size: 12px;">of forest management in the future.</span></p>
312

Conservação da biodiversidade por empresas de capital aberto: uma análise através da metodologia LIFE / Biodiversity conservation by open capital companies: an analysis through the LIFE certification methodology

Reale, Ricardo 29 July 2016 (has links)
A antropização dos ambientes naturais vem ocasionando efeitos adversos aos sistemas ecológicos, acelerando a perda da biodiversidade. Como resultado, as alterações climáticas tornaram-se mais frequentes e com maiores proporções de desastres. Por tanto, é imperativo que novas formas de exploração dos recursos naturais sejam incorporadas pelos diversos setores econômicos, diminuindo, minimizando e/ou mitigando os impactos negativos à biodiversidade e aos serviços ecossistêmicos. Este trabalho avaliou os relatórios socioambientais de todos os empreendimentos que permaneceram listados nos Índices de Sustentabilidade Empresarial da bolsa de valores de São Paulo entre 2005 e 2014, analisando se os empreendimentos reconhecidos como os detentores das melhores práticas sustentáveis contribuem, voluntariamente, para a conservação, recuperação e manutenção dos serviços ecossistêmicos nos biomas e regiões hidrográficas onde estão instalados. As coletas e as análises de dados foram realizadas através da metodologia da certificação LIFE (Lasting Initiative For Earth), que qualifica e quantifica os impactos ambientais negativos à biodiversidade ocasionados pelos processos produtivos de empreendimentos de qualquer porte ou setor. A metodologia LIFE também qualifica e quantifica as ações de conservação que os empreendimentos desenvolvem e, principalmente, indica quais são as ações conservacionistas que deverão ser desenvolvidas para minimizar e/ou mitigar, minimamente, os impactos ambientais ocasionados aos ecossistemas por meio dos processos produtivos. Das 11 empresas avaliadas, 10 não desenvolvem ações de conservação suficientes para mitigarem os impactos ambientais nos biomas e regiões hidrográficas a que pertencem, mesmo sendo sete delas diretamente dependentes dos serviços ecossistêmicos. Apenas a empresa E9, do setor florestal (Papel e Celulose), mitigou os impactos e reconheceu que as ações conservacionistas privilegiam e favorecem o desenvolvimento de suas atividades produtivas e na qualidade de seus produtos. Todas as demais empresas listadas no ISE, avaliadas neste estudo, demonstraram que não desenvolveram, voluntariamente, ações conservacionistas que minimizem e/ou mitiguem impactos ambientais à biodiversidade com o intuito de manterem e restaurarem os serviços ecológicos dos quais se beneficiam. Propõe-se, então, que a metodologia da certificação LIFE pode ser utilizada como um instrumento adicional de gestão ambiental, auxiliando empresas a fortalecerem seus posicionamentos de sustentabilidade frente à bolsa de valores paulista e aos demais stakeholders. / Anthropization of natural environments has caused adverse effects to ecological systems, accelerating the loss of biodiversity. As a result, climate change has become more frequent with bigger disaster proportions. Therefore, it is imperative that new forms of exploitation of natural resources are incorporated into the various economic sectors, reducing, minimizing and/or mitigating the negative impacts on biodiversity and ecosystem services. This study evaluated the social environmental reports of all companies that remained listed in the Corporate Sustainability Index (ISE portfolio in Portuguese) of the São Paulo Stock Exchange between 2005 and 2014, analyzing whether the recognized enterprises as holders of the best sustainable practices contribute voluntarily to the conservation, recovery and maintenance of ecosystem services in the biomes and hydrographic regions where they are installed. The data collection and analysis were realized with LIFE Certification methodology (Lasting Initiative For Earth), which qualifies and quantifies the negative environmental impacts on biodiversity caused by the production processes of enterprises of any size or sector. The LIFE methodology also qualifies and quantifies conservation actions that enterprises develop and mainly indicates what the conservation actions that should be developed to minimize and/or mitigate, minimally, the environmental impacts caused to ecosystems by means of production processes. 11 companies from 10 analyzed do not develop sufficient conservation actions to mitigate the environmental impacts in the biomes and hydrographic regions to which they belong, even though seven of them directly dependent on ecosystem services. Just E9 company, forestry sector (Cellulose and Paper), mitigated the impacts and recognized that conservation actions emphasize and promote the development of productive activities and the quality of its products. All other companies listed on the ISE, evaluated in this study showed that no developed voluntarily conservation actions to minimize and/or mitigate environmental impacts to biodiversity in order to maintain and restore the ecological services that benefit. It is proposed therefore that the LIFE certification methodology can be used as an additional tool for environmental management, helping companies strengthen their positions facing the sustainability of the São Paulo stock exchange and other stakeholders.
313

Ecological impacts of ash dieback in Great Britain

Hill, Louise January 2017 (has links)
Ash dieback is a severe disease of ash trees (Fraxinus spp.), caused by the invasive fungus Hymenoscyphus fraxineus. In its native East Asia, H. fraxineus is a harmless endophyte, but since its accidental import into Europe in the early 1990s it has infected over 90% of ash trees in some areas, with long-term mortality sometimes exceeding 90%. The disease was discovered in Great Britain in 2012, and has since spread rapidly. This thesis investigates some of the possible impacts on biodiversity, ecosystem functioning, and society, and in doing so identifies ways to alleviate some impacts. Britain has only 13% tree cover (among the lowest in Europe), so may be particularly vulnerable to ash loss. Better understanding of the effects and how to minimise them is critical to deliver an evidence-based response. First, we investigated impacts in woodlands by experimentally killing woodland ash trees by ring-barking. We found no short-term effect of ash loss on ground flora or earthworm communities, or on the regeneration or growth of other woody species. Observational evidence suggested that remaining canopy trees rapidly filled gaps left by ash, perhaps contributing to stability. Our woodlands appeared to be remarkably resilient to ash loss, although there may be long-term effects or impacts on other species that this experiment failed to observe. To investigate broader-scale impacts, we required high-quality abundance maps for ash and other trees across Britain. Using species distribution modelling and random forest regression, we developed a protocol to produce abundance maps from readily available data. We tested the predictive power of the resulting maps using cross validation. Our maps are the best available for abundance of British tree species, and will be useful across a wide range of disciplines. We then used them to model ecosystem vulnerability to ash loss, based on the abundance of ash and other tree species, and their ecological trait similarity. We identified areas at risk of the largest impacts, and produced guidance for positive management actions to minimise ecological change. Lastly, we investigated the financial impacts of ash dieback, estimating the total cost to Britain at &pound;9.2 billion. This figure is many times larger than the value of lost trade if biosecurity were improved to prevent future invasions, questioning the validity of financial arguments against biosecurity. We also found that loss of ecosystem services accounted for less than a third of the total cost, suggesting that ecosystem service assessments may miss a large proportion of the true cost of biodiversity loss. Overall, we found that some impacts may be less than expected, such as local effects on woodland ground flora, and others, such as the economic cost, may be much larger than expected. However, the resilience of ecosystems to a major shock such as loss of a common species, and actions to mitigate the impacts, depend on having a diversity of other trees present. The ash dieback outbreak highlights the importance of preventing other severe pests and diseases of trees from being introduced; something that has been increasing exponentially, largely due to international trade in trees. This thesis provides further firm evidence that there is an ecological and social imperative to halt this trend.
314

Indicadores de avaliação de capital natural e de oferta e demanda de serviços ecossistêmicos para a Região Metropolitana de Curitiba / Evaluation indicators of natural capital and of supply and demand of ecosystem services in Metropolitan Region of Curitiba

Amanda Silveira Carbone 20 February 2019 (has links)
Esta pesquisa se situa no campo do planejamento territorial e da sustentabilidade urbana, com foco na conservação da biodiversidade e na provisão de serviços ecossistêmicos. Parte-se do pressuposto que a urbanização, embora estimule o progresso econômico, social e cultural, tem impulsionado problemas como a degradação ambiental e a falta de saneamento e que é necessário um planejamento do território em nível metropolitano, visando a manutenção do capital natural e a provisão de serviços ecossistêmicos essenciais ao bem-estar humano e à qualidade de vida, de forma sustentável. Assim, o objetivo deste estudo foi propor um conjunto de indicadores de avaliação de capital natural e de serviços ecossistêmicos para regiões metropolitanas, tendo como recorte empírico a Região Metropolitana de Curitiba. O conjunto de indicadores foi construído a partir de uma base teórica e posteriormente validado por especialistas utilizando-se o método Delphi. O conjunto de indicadores proposto e validado por especialistas apresenta embasamento teórico e flexibilidade para aplicação em diferentes contextos. A situação na RMC demonstra uma tendência de degradação do capital natural e consequente comprometimento na provisão de água em longo prazo, com destaque para a bacia do rio Ribeira. Verificou-se a necessidade de se ampliar, em grande parte da RMC, a implementação das políticas de proteção da biodiversidade, estimular a criação de novas unidades de conservação e fortalecer o monitoramento do uso do solo. / This research is situated in the field of territorial planning and urban sustainability, with focus on biodiversity conservation and ecosystem service provision. The assumption is that urbanization, while stimulating economic, social and cultural progress, has driven problems such as environmental degradation and lack of sanitation and that it is necessary to plan the territory at the metropolitan level, aiming at maintaining natural capital and providing ecosystem services essential to human well-being and quality of life in a sustainable way. Thus, the objective of this study was to propose a set of indicators for the evaluation of natural capital and ecosystem services on metropolitan regions, having as an empirical cut the Metropolitan Region of Curitiba. The set of indicators was built from a theoretical basis and then validated by experts using the Delphi method. The set of indicators proposed and validated presents flexibility for application in different contexts. The situation in the MRC demonstrates a trend of degradation of natural capital and consequent impairment in long term water provision, with emphasis in the Ribeira river basin. It is necessary to expand implementation of policies to protect biodiversity, to stimulate the creation of new conservation units and to strengthen the monitoring of land use.
315

Serviços ecossistêmicos hídricos em paisagens florestais fragmentadas: um caminho para a conservação da Mata Atlântica / Water ecosystem services in fragmented forest landscapes: a way for the Atlantic Forest conservation

Vivian Cristina dos Santos Hackbart 12 December 2016 (has links)
A perspectiva de elaborar planejamentos em áreas de floresta a partir da concepção de serviços ecossistêmicos, principalmente serviços hídricos, expandiu-se em muito pouco tempo, principalmente porque essa estratégia evidencia, claramente, como a perda desse sistema natural por atividades do homem pode causar perdas irreparáveis ao seu próprio bem-estar. Trabalhar planejamento ambiental sob esse enfoque exige adoção de uma forte base teórica sobre serviços hídricos; um modelo que permita comparar paisagens em diferentes condições de uso e conservação de floresta; e clareza sobre o tipo de valoração empregado na identificação dos limites de perdas de floresta, de forma a não comprometer a oferta necessária desses serviços. Este estudo defende que em Mata Atlântica é possível reconhecer a dependência direta entre quantidades de floresta, de usos humanos e de serviços hídricos em bacias hidrográficas e, por ela, valorar a oferta desses serviços e comparar paisagens. Para fortalecer esse argumento foram selecionadas 27 unidades territoriais da região do Vale do Paraíba (São Paulo, Br) a partir da aplicação de um modelo espacial baseado na extração de bacias hidrográficas originadas da intersecção de hexágonos com percentuais de floresta, campo antrópico e silvicultura. Em cada unidade foram obtidos dados de 13 parâmetros físico-quimico-biológicos nas estações seca e chuvosa, que foram hierarquizados pelo Random Forest de forma a aferir suas relações com a quantidade de floresta e formular índices de sete serviços hídricos. Os parâmetros que se mostraram mais adequados para monitoramento dos serviços hídricos frente aos ganhos de floresta, com grande peso hierárquico na formulação dos índices, foram turbidez, condutividade e sólidos totais dissolvidos. Os índices obtidos permitiram apontar que para manter 50% do potencial total dos sete serviços hídricos em paisagens com campos antrópicos são necessárias mais de 40% de cobertura florestal, mas os melhores ganhos potenciais de serviços ocorreram a partir de 60%. Quando a unidade territorial é a combinação entre floresta e silvicultura há maior oferta de serviços hídricos com menor quantidade de floresta, porém o manejo da madeira e a presença de áreas degradadas mudaram completamente esse cenário favorável / The possibility of elaborate planning in forest areas from notion of ecosystem services, especially water services, expanded in a short time, mainly because this strategy shows how the loss of this natural system by human activities can cause losses irreparable to their own well-being. Working environmental planning under this approach requires the adoption of a strong theoretical basis for water services; a model for comparing landscapes under different conditions of use and conservation of forest; and insight about the type of valuation used in the identification of the limits of forest loss in order not to compromise the necessary supply of these services. This study argued that in the Atlantic Forest is possible to recognize the direct dependency between amounts of forest, human uses and water services in watersheds and, through it, assess the provision of these services and compare landscapes. In order to defend this argument were selected 27 territorial units of the Vale do Paraíba region (Sao Paulo, Brazil) from the application of a spatial model based on the extraction of river basins originating hexagons intersection with percentages of forest, anthropic field and forestry. In each unit were obtained data from 13 physical-chemical-biological parameters in two seasons, which were ranked by Random Forest in order to support its relations with the amount of forest as well as the index formulation for seven water services. The parameters more suitable for monitoring water in front of services to forest gains, and with large hierarchical influence the formulation of the indices, were turbidity, conductivity and total dissolved solids. The indices obtained allowed to point out that to keep 50% of the total potential of the seven water services in landscapes with anthropic fields (pasture) are required more than 40% forest cover, but the best servi4e potential gains occurred from 60%. When the territorial unit is a combination of forest and forestry there is more supply of water services with less forest, but the management of timber and the presence of degraded areas completely changed this favorable scenario
316

Serviços ecossistêmicos hídricos em paisagens florestais fragmentadas: um caminho para a conservação da Mata Atlântica / Water ecosystem services in fragmented forest landscapes: a way for the Atlantic Forest conservation

Hackbart, Vivian Cristina dos Santos 12 December 2016 (has links)
A perspectiva de elaborar planejamentos em áreas de floresta a partir da concepção de serviços ecossistêmicos, principalmente serviços hídricos, expandiu-se em muito pouco tempo, principalmente porque essa estratégia evidencia, claramente, como a perda desse sistema natural por atividades do homem pode causar perdas irreparáveis ao seu próprio bem-estar. Trabalhar planejamento ambiental sob esse enfoque exige adoção de uma forte base teórica sobre serviços hídricos; um modelo que permita comparar paisagens em diferentes condições de uso e conservação de floresta; e clareza sobre o tipo de valoração empregado na identificação dos limites de perdas de floresta, de forma a não comprometer a oferta necessária desses serviços. Este estudo defende que em Mata Atlântica é possível reconhecer a dependência direta entre quantidades de floresta, de usos humanos e de serviços hídricos em bacias hidrográficas e, por ela, valorar a oferta desses serviços e comparar paisagens. Para fortalecer esse argumento foram selecionadas 27 unidades territoriais da região do Vale do Paraíba (São Paulo, Br) a partir da aplicação de um modelo espacial baseado na extração de bacias hidrográficas originadas da intersecção de hexágonos com percentuais de floresta, campo antrópico e silvicultura. Em cada unidade foram obtidos dados de 13 parâmetros físico-quimico-biológicos nas estações seca e chuvosa, que foram hierarquizados pelo Random Forest de forma a aferir suas relações com a quantidade de floresta e formular índices de sete serviços hídricos. Os parâmetros que se mostraram mais adequados para monitoramento dos serviços hídricos frente aos ganhos de floresta, com grande peso hierárquico na formulação dos índices, foram turbidez, condutividade e sólidos totais dissolvidos. Os índices obtidos permitiram apontar que para manter 50% do potencial total dos sete serviços hídricos em paisagens com campos antrópicos são necessárias mais de 40% de cobertura florestal, mas os melhores ganhos potenciais de serviços ocorreram a partir de 60%. Quando a unidade territorial é a combinação entre floresta e silvicultura há maior oferta de serviços hídricos com menor quantidade de floresta, porém o manejo da madeira e a presença de áreas degradadas mudaram completamente esse cenário favorável / The possibility of elaborate planning in forest areas from notion of ecosystem services, especially water services, expanded in a short time, mainly because this strategy shows how the loss of this natural system by human activities can cause losses irreparable to their own well-being. Working environmental planning under this approach requires the adoption of a strong theoretical basis for water services; a model for comparing landscapes under different conditions of use and conservation of forest; and insight about the type of valuation used in the identification of the limits of forest loss in order not to compromise the necessary supply of these services. This study argued that in the Atlantic Forest is possible to recognize the direct dependency between amounts of forest, human uses and water services in watersheds and, through it, assess the provision of these services and compare landscapes. In order to defend this argument were selected 27 territorial units of the Vale do Paraíba region (Sao Paulo, Brazil) from the application of a spatial model based on the extraction of river basins originating hexagons intersection with percentages of forest, anthropic field and forestry. In each unit were obtained data from 13 physical-chemical-biological parameters in two seasons, which were ranked by Random Forest in order to support its relations with the amount of forest as well as the index formulation for seven water services. The parameters more suitable for monitoring water in front of services to forest gains, and with large hierarchical influence the formulation of the indices, were turbidity, conductivity and total dissolved solids. The indices obtained allowed to point out that to keep 50% of the total potential of the seven water services in landscapes with anthropic fields (pasture) are required more than 40% forest cover, but the best servi4e potential gains occurred from 60%. When the territorial unit is a combination of forest and forestry there is more supply of water services with less forest, but the management of timber and the presence of degraded areas completely changed this favorable scenario
317

From Maintenance To Stewardship: Green Stormwater Infrastructure Capacity In Vermont Towns & Design And Participatory Processes To Provide Cultural Ecosystem Services

Greenleaf, Holly Lee 01 January 2019 (has links)
The impervious surfaces of built landscapes create stormwater runoff that causes water quantity and quality problems downstream, upsetting natural hydrology and harming aquatic ecosystems. Green stormwater infrastructure (GSI) includes practices that reduce the amount of stormwater runoff and the pollutants it carries utilizing plants, soils, and other materials to capture, store, reuse, infiltrate, evapotranspire, and filter stormwater. GSI helps to restore developed landscapes, mimicking natural hydrologic processes and providing important water treatment functions as well as beneficial green spaces in urban areas. However, there are many challenges associated with the implementation and maintenance of GSI in our communities and cultures. This research explores the human side of implementing GSI, investigating current maintenance capacities in rural and urban settings, and exploring multifunctional benefits of GSI to provide both biophysical and cultural ecosystem services (CES). Research goals include characterizing the current state of GSI implementation and maintenance in municipalities in the State of Vermont (USA) and eliciting lessons that can inform GSI design practices and policies. Multifunctional GSI design objectives that provide and enhance CES are described, revealing opportunities to instill values and a sense of stewardship for the health wellbeing of people and ecosystems. The first chapter provides relevant topical background to set the stage for the latter two chapters. The second chapter analyzes results from a survey of municipal officials in Vermont that occurred as part of NSF-EPSCoR-funded Basin Resilience to Extreme Events project research on stormwater management. The survey included questions about GSI and maintenance practices in place and perceptions of visual appeal and ability to maintain bioretention systems shown in landscape visualizations. Results show that visual appeal and perceived maintainability of vegetated bioretention practices do not appear to be significant barriers to adoption and operation, but stormwater policy and funding are shown to be both significant barriers and solutions to implementing and maintaining GSI in Vermont municipalities. Additionally, urban and rural towns provide very different contexts for implementing and maintaining GSI in Vermont and characteristics of development patterns and maintenance capacity should be considered in policy, regulations, outreach, and education. The third chapter offers a literature review, guided by a CES framework, of design elements that can be included in GSI to create multifunctional urban green spaces. CES categories of aesthetic, recreation, education, sense of place, social capital, and stewardship benefits framed a set of design elements, principles, practices, and documented benefits to guide multifunctional design of GSI. Findings include the importance of participatory processes to elicit diverse landscape values, visible water pathways, biodiversity, spaces for creative use, accessibility, interaction with water, interpretive signage, and artful and biophilic design features to enhance feelings of preference, pleasure, relaxation, learning, connection, and inclusion. The health and wellbeing of water and people must be integrated into the design of GSI for cities to be ecologically functional and culturally meaningful to their populations.
318

Identification et évaluation des services écosystémiques rendus par les habitats coralligènes / Identification and valuation of ecosystem services provided by coralligenous habitats

Thierry de Ville d'Avray, Laure 29 June 2018 (has links)
Le bassin méditerranéen est reconnu comme un "point chaud" de biodiversité soumis à de fortes pressions anthropiques. En domaine marin, les habitats coralligènes participent grandement à cette biodiversité et leur situation côtière les rend accessibles aux hommes. La thèse porte sur l'identification et l'évaluation de leurs services écosystémiques. J’ai utilisé le concept de \textit{service écosystémique} à une échelle locale : la Baie de Marseille (anthropisée) et le Parc national de Port-Cros (sous pression humaine minimale). Le premier volet de la thèse porte sur l'identification et la description des services rendus par les habitats coralligènes dans les zones d’étude. Les services les plus évidents (production de ressource alimentaire, production de corail rouge et sites de plongée) font l’objet d’une étude plus approfondie. Le deuxième volet de la thèse teste le concept de cascade de service écosystémique d'Haines-Young et Potschin pour décrire les éléments et fonctions de l'écosystème impliqués dans chaque service, les bénéficiaires et les types de valeurs économiques qui en sont issus, et des indicateurs pour mesurer chaque niveau de la cascade. Le troisième volet de la thèse porte sur une analyse de l'activité de plongée sur les habitats coralligènes de la baie de Marseille. Le dernier volet de la thèse est une étude des préférences déclarées dans les secteurs de Marseille et Port-Cros concernant les services rendus par les habitats coralligènes, grâce à la méthode des choix discrets. Ce dernier volet comprend une étude de l’impact de la connaissance initiale et de l’apport d’information dans la formation des préférences. / The Mediterranean basin is recognized as a "hotspot" of biodiversity subjected to strong anthropic pressures. In the marine domain, coralligenous habitats greatly contribute to the basin’s biodiversity and their coastal location makes them accessible to humans. The thesis attempts to identify and economically evaluate some of those ecosystem services. I used the concept of \textit{ecosystem service} at a local scale, focusing on the Bay of Marseille (anthropized) and the Port-Cros national park (under minimal human pressure). The first part of the thesis deals with the identification and description of the services rendered by coralligenous habitats in the study areas. The second part of the thesis describes the provisionning services through the application of the concept of ecosystem service cascade as developed by Haines-Young and Potschin. This approach helps to identify the elements and functions of the ecosystem involved in each service, the human beneficiaries and the types of economic benefits associated with the services. This chapter also proposes variables to measure each level of the cascade. The third part of the thesis deals with an analysis of the relationship between the presence of coralligenous habitat and the frequency of dives in the Bay of Marseille. The last part of the thesis employs the method of discrete choices experiment to study the declared preferences in the study areas of Marseille and Port-Cros concerning the services rendered by the coralligenous habitats. This analysis provided insight into how preferences can evolve as initial knowledge is enhanced through the provision of additional information.
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Characterization of microbial communities in Technosols constructed for industrial wastelands restoration

Hafeez, Farhan 06 September 2012 (has links) (PDF)
Increasing soil degradation and its consequences on overall ecosystem services urge for restoration strategies. Construction of Technosols through assemblage of treated soil and industrial wastes is an innovative technology for the restoration of polluted land and re-use of industrial by-products. Recent studies have evidenced that Technosols could support ecosystemic services such as primary production but the knowledge about other soil functions, such as biogeochemical cycling, is limited. Due to the significant contribution of microbial communities to soil functioning, this PhD work was carried out to study the effect of the type of Technosol on microbial communities with a focus on functional guilds involved in N cycling. For this purpose, the abundance and diversity of the total bacterial community and the abundance of crenarchaeal community together with the abundance and activities of the nitrifying and denitrifying communities were investigated in two types of Technosols. Results demonstrated that diversity and composition of the bacterial community were similar to 'natural soils' and were not significantly different between the two Technosols with Proteobacteria being the dominant phylum (50-80%). The bacterial ammonia oxidizers were greater in number than crenarchaeal ammonia oxidizers but also correlated to the potential nitrification activity suggesting that bacteria are the dominant ammonia oxidizers in Technosols. The abundance of both the ammonia oxidizers and the denitrifiers were in the same range than that observed in other soil systems. Analyses of the vertical distribution of the activity and abundance of N-cycling communities in the Technosols showed a significant depth-effect, which was more important than the Technosol type-effect. Technosols physicochemical properties and the abundance of the bacterial ammonia oxidizers were the main drivers of the nitrification activity whereas the denitrification activity was controlled mainly by the Technosols physicochemical properties and, to a minor extent, by the abundances of the nirS denitrifiers. The estimation of the functional stability of the denitrification process against the heat-drought stresses revealed that Technosol exhibited the high resistance and resilience in comparison to the thermally treated soil. This work highlighted the potential of constructed Technosols to ensure the N cycling ecosystem services, along with a high capacity to resist and recover from environmental stresses, suggesting that construction of Technosols is a promising technology and a solution for the restoration of industrial wastelands and waste recycling
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Recreational ecosystem service benefits from the Chestermere Lake Reservoir : value for day use non-resident visitors

Bewer, Robert January 2012 (has links)
Irrigation infrastructure provides many ecosystem service (ES) benefits that enhance the well-being of Albertans and is central to economic activity in southern Alberta. Management of irrigation infrastructure and water resources is becoming increasingly challenging as Alberta’s population and economy grows. Past water allocation decisions have not generally considered the need of ecosystems leading to declining ecosystem health, and changes to provision of ES benefits in Alberta. The goals of current Alberta government policy include changing how water and land is managed to ensure that ecosystem health and ES provision is maintained. The research in this thesis concentrates on establishing the value of recreational ES benefits provided by the Chestermere Lake Reservoir, and obtaining information on the spatial aspects and visitor characteristics. A mixed method approach is used combining a qualitative discussion with a quantitative analysis using a geographic information system (GIS) and the travel cost method (TCM). The selection of the mixed method and combined GIS-TCM approach was based on past success in previous studies. The findings reveal a substantial value for recreational ES benefits provided by the Chestermere Lake Reservoir occurring within a limited area similar to other studies of recreational benefits from reservoirs. The findings of this research provide information for decisions makers, water infrastructure managers, and water transfer participants when assessing the impact of planned actions. Further research is recommended to build upon the findings of this study and further expand the available information on ES benefits to include all ES provided by southern Alberta. / x, 125 leaves : col. ill. ; 29 cm

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