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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.
491

Transcriptome analysis of vascular cavity formation in soybean cv. 'Yukihomare' seedlings in response to flooding

Waldenmaier, Hans Eugene 16 August 2011 (has links)
No description available.
492

Prediction of Travel Time and Development of Flood Inundation Maps for Flood Warning System Including Ice Jam Scenario. A Case Study of the Grand River, Ohio

Lamichhane, Niraj 23 May 2016 (has links)
No description available.
493

Assessing Climatic Hazards in Coastal Socio-Ecological Systems using Complex System Approaches

Nourali, Zahra 31 May 2024 (has links)
Coastal socio-ecological systems face unprecedented challenges due to climate change, with impacts encompassing long-term, chronic changes and short-term extreme events. These events will impact society in many ways and prompt human responses that are extremely challenging to predict. This dissertation employs complex systems methods of agent-based modeling and machine learning to simulate the interactions between climatic stressors such as increased flooding and extreme weather and socio-economic aspects of coastal human systems. Escalating sea-level rise and intensified flooding has the potential to prompt relocation from flood-prone coastal areas. This can reduce flood exposure but also disconnect people from their homes and communities, sever longstanding social ties, and lower the tax base leading to difficulties in providing government services. Chapter 2 demonstrates a stochastic agent-based model to simulate human relocation influenced by flooding events, particularly focusing on the responses of rural and urban communities in coastal Virginia and Maryland. The findings indicate that a stochastic, bottom-up social system simulator is able to replicate top-down population projections and provide a baseline for assessing the impact of increasingly intense flooding. Chapter 3 leverages this model to assess how incorporating heterogeneity in relocation decisions across socio-economic groups impacts flood-induced relocation patterns. The results demonstrate how this heterogeneity leads to a decrease in low-income households, yet a rise in the proportion of elderly individuals in flood-prone regions by the end of the simulation period. Flood-prone areas also exhibit distinct income clusters at the end of simulation time horizon compared to simulations with a homogenous relocation likelihood. Lastly, Chapter 4 explores relationships between extreme weather and agricultural losses in the Delmarva Peninsula. Existing research on climatic impacts to agriculture largely focuses on changes to major crop yields, providing limited insights into impacts on diverse regional agricultural systems where human management and adaptation play a large role. By comparing various multistep modeling configurations and machine learning techniques, this work demonstrates that machine learning methods can accurately simulate and predict agricultural losses across the complex agricultural landscape that exists on the Delmarva peninsula. The multistep configurations developed in this work are able to address data imbalance and improve models' capacity to classify and estimate damage occurrence, which depends on multiple geographical, seasonal, and climatic factors. Collectively, this work demonstrates the potential for advanced modeling techniques to accurately replicate and simulate the impacts of climate on complex socio-ecological systems, providing insights that can ultimately support coastal adaptation. / Doctor of Philosophy / Coastal areas are facing increasing challenges from climate change, including rising sea levels and extreme weather conditions. This dissertation explores socio-economic consequences of these adverse environmental changes for coastal communities. Disruptive repetitive flooding due to exacerbated rise in sea levels is one of these consequences that may eventually leave some highly exposed coastal communities no alternative but migrating from their residences. Focusing on coastal Virginia and Maryland, Chapter 2 develops a data-informed model that can simulate individual relocation decisions and assess how they impact population changes and migration patterns. Chapter 3 employs this model to investigate how future changes in sea levels affect diverse socio-economic groups, their relocation decisions, and the resulting collective migration flows in flood-prone areas. We found that considering demographic differences leaves highly flood-prone areas with less low-income households, higher elderly individuals, and more economic clusters compared to simulations where these differences are not accounted for. Chapter 4 uses machine learning models to simulate the economic impact of extreme weather events as another manifestation of climate change on the agriculture in the Delmarva Peninsula. Through data-based modeling techniques, we identify the climatic conditions most responsible for agricultural losses and recognize modeling choices that enhance our predictive ability. Collectively, this dissertation demonstrates how sophisticated modeling techniques can be used to better understand the complex ways in which climate change will impact human society, with the ultimate goal of supporting adaptation strategies that can better address these impacts.
494

Kampen mellan vatten och fastland : Att bygga broar mellan klimatanpassning och kommunal kapacitet. Fallstudie av Ystad och Karlstad kommun

Sjöstrand, Rebecka, Persson, Ellen January 2024 (has links)
Klimatförändringar medför nya utmaningar som både ställer krav och sätter prov på det svenska samhällets förmåga att kunna anpassa sig efter nya förutsättningar. Översvämningar, skyfall, erosion och förhöjda havsnivåer orsakar redan idag allvarliga problem inom många delar av landet. Idag finns det kunskap kring klimatförändringar samt vad som behövs för att skapa hållbara och robusta samhällen, däremot kan vägen dit se annorlunda ut. Syftet med arbetet grundar sig därför i att belysa de svårigheter som uppstår under det kommunala klimatanpassningsarbetet, det genom att fokusera på två svenska kommuner, Karlstad och Ystad. Genom kvalitativa intervjuer och granskning översiktsplanerna har empirin insamlats och därefter analyserats tematiskt. Studiens teoretiska ansats utgår från institutionell kapacitet och tillsammans med empiri har det svenska klimatanpassningsarbetets utmaningar studerats. Brister i kunskap, resurser, samverkansförmåga samt mobilisering av dessa medel framträder som huvudsakliga svårigheter. Det finns däremot ingen universell modell för att förbättra klimatanpassningsarbetet, då kommunernas förutsättningar varierar. / Climate change poses new challenges that both demand and test the adaptability of the Swedish society. Floods, heavy rainfall, erosion, and rising sea levels already cause serious problems in many parts of the country. While there is knowledge about climate change and what is needed to create sustainable and resilient communities, the path may vary. This study aims to illuminate the difficulties in municipal climate adaptation, focusing on two Swedish municipalities, Karlstad and Ystad. Through qualitative interviews and reviewing the municipalities strategic plans, empirical data was collected and thematically analyzed. The study's theoretical framework is based on institutional capacity, examining the challenges of Swedish climate adaptation efforts. Primary difficulties include knowledge gaps, resource limitations, collaboration issues, and mobilization of these resources. However, due to the variety in municipal conditions, there is no universal model to improve climate adaptation.
495

Development and Application of a Spatially Distributed Travel Time Model for Risk Screening and Parameter Influence Evaluation in Rainfall-Runoff Response : Ensemble Approach to Risk Screening in Urban Watersheds / Utveckling en avrinningsmodell med tillämpande spatialt fördelade rinntider för översiktlig riskanalys och utvärdering av parameterinflytande

Pöldma, Sofia Stone January 2024 (has links)
In recent years, climate change has intensified the frequency of severe rainfall events, raising concerns, particularly in urban areas where impervious surfaces dominate. The resultant reliance on man-made drainage increases pluvial flooding risks, threatening infrastructure and urban resilience. As the global population increasingly shifts to urban living, the vulnerability to flooding grows. Understanding how areas respond to rainfall is crucial for proactive flood risk mitigation. Available hydrological models offer insights and predictions, but are often linked with long simulation times and high computational cost. Semi-distributed models, like the Spatially Distributed Travel Time (SDTT) approach, offer simplified model formulations suitable for screening applications. This thesis extends Ekeroth's (2022) SDTT model for watershed delineation and travel time formulations, focusing on ensemble runs of multi-input rainfall/infiltration scenarios. As there is often many uncertain factors in hydrological modeling, there is a need for faster models capable of generating a distribution of scenarios to represent the uncertainty of real systems. Even a quick and simple model should account for the multifaceted aspects of urban flooding, including rainfall-infiltration dynamics and the variations in rainfall intensity. Script modules were developed to analyze rainfall severity, peak discharge distribution, and parameter impact efficiently. In three urban watersheds with an average size of 0.45 km2, 120 scenarios distinguished by intensity distribution, rainfall duration, soil composition of pervious areas, and antecedent moisture conditions, were simulated within approximately 3.5 minutes, enabling comprehensive hydrological analysis. The successful implementation of the new modules implicate a promising tool for hydrological risk-screening analysis in urban environments, although further research should investigate incorporating probability-based scenarios and bigger input rainfall datasets. / Under senare år har klimatförändringarna intensifierat förekomsten av skyfall, något som är särskilt oroväckande i stadsområden där marktäckningen huvudsakligen består av hårdgjorda ytor. Genom att asfaltera och bygga försvinner markens naturliga infiltrationsförmåga. Detta leder till ett ökat beroende av konstgjorda dräneringssystem som sällan är dimensionerade för särskilt intensiva regnhändelser. Urbana översvämningar innebär inte bara ett hot mot infrastruktur och den bebyggda miljön, men den globala befolkningens ökade bosättning i urbana områden medför att sårbarheten vid översvämningar ökar även den. För att kunna hantera översvämningsrisken i ett urbant område är förståelse för avrinningsområdets respons till ett skyfall viktigt. Det finns hydrologiska modeller på marknaden som erbjuder prognoser, men dessa är oftast baserade på komplexa fysiska beskrivningar som medför långa processtider och beräkningskostnader. Samtidigt finns nytänkande modeller som skär ner på processtiderna genom att minska den spatiala upplösningen på beräkningarna, såsom SDTT (Spatially Distributed Travel Time) formuleringen, som erbjuder förenklade analyser lämpliga som screeningverktyg. Denna studie utvidgar Ekeroths (2022) SDTT-modell med fokus på ensemblekörningar av regn- och infiltrationsscenarier. Eftersom det ofta finns flertalet osäkra faktorer i hydrologisk modellering finns ett behov av snabbare modeller som kan genera en fördelning av möjliga utfall givet olika scenarier. Samtidigt behöver även en snabb och enkel modell beakta de mångfacetterade aspekterna av urbana översvämningar, exempelvis gällande dynamiken mellan regn och infiltration och skyfallsegenskaper. Kodmoduler utvecklades för att effektivt analysera utfallen av regnscenarierna och att finna de mest allvarliga händelserna, fördelningen av värden inom de simulerade utfallen, samt inflytandet från parametrarna som definierar scenarierna. I tre urbana avrinningsområden med en genomsnittlig storlek på 0.45 km2 simulerades 120 scenarier inom 3,5 minuter, vilket möjliggör hydrologisk analys på en hanterbar tid. Implementeringen av de nya modulerna pekar mot ett lovande verktyg för hydrologisk risk-screeninganalys i urbana miljöer. Samtidigt bör framtida studier fortsatt undersöka möjligheten att inkludera sannolikhetsbaserade scenarier och körning av större dataset.
496

Adapting Properties to Climate Risks and its Financial Impact and EU Compliance : Case Study on a Real Estate Company / Anpassning av fastigheter till klimatrisker och dess ekonomiska konsekvenser samt EU-kompatibilitet : En fallstudie av ett fastighetsbolag

Chienh, Jennifer, Mian, Ozair January 2024 (has links)
As climate change progresses, extreme weather events such as heatwaves, heavy rainfall, and flooding are expected to become more common and frequent. Increased climate-related risks pose multiple threats to society, including damage to properties and infrastructure, loss of human lives, and economic instability. This necessitates property owners to adapt to future climate scenarios. To direct capital towards sustainable investments and contribute to a green transition, the EU has introduced measures such as the EU Taxonomy, and the Corporate Sustainability Reporting Directive (CSRD), which an increasing number of companies will gradually be covered by. Many companies are unprepared for the growing demands of the CSRD, which must be reported according to the European Sustainability Reporting Standards (ESRS).  The purpose of this report is to identify the climate-related risks faced by real estate companies, focusing on properties for public use, and to highlight the economic consequences of these risks. Furthermore, the report aims to contribute to the development of methods for ongoing management of climate risks, including prioritization and action planning, as well as exploring how real estate companies can integrate climate adaptation in line with ESRS. The development of the model for climate and vulnerability analyses is based on previous analyses conducted by various actors and adapted to ESRS. Semi-structured interviews have been conducted with industry players to gain insight into how the work on climate adaptation of properties is progressing and its financial impact. To investigate how market value can be affected by preventive climate adaptation measures compared to post-climate event costs, a Discounted Cash Flow Analysis was performed. A five-step model has been developed, including: mapping of the property portfolio, identifying climate-related risks, risk analysis and property-specific characteristics, risk assessment, and implementation of climate adaptation measures. Investments in climate adaptation measures are cheaper in the long run than not adapting, as the costs of damage are often much higher and have a more negative impact on property values. The work on climate adaptation is an ongoing process, and sustainability reporting according to CSRD is complex. Insurance companies only compensate for damages classified as "unforeseen and sudden." This means that properties need to be climate-adapted to be insurable. Without insurance protection, it also becomes difficult to obtain bank loans, as properties are often used as collateral. / I takt med klimatförändringarna förväntas extremväder som värmeböljor, skyfall och översvämningar bli allt vanligare och mer frekventa. Ökade klimatrelaterade risker hotar samhället på många sätt, såsom skador på fastigheter och infrastruktur, människoliv och ekonomisk stabilitet. Vilket ställer krav på fastighetsägare att klimatanpassa utifrån framtida klimatscenarier. För att styra kapital mot hållbara investeringar och bidra till en grön omställning har EU bland annat infört EU-taxonomin, och Corporate Sustainabilty Reporting Directive (CSRD), som allt fler företag successivt kommer att omfattas av. Många företag är inte förberedda på de ökande kraven från CSRD som ska redovisas enligt European Sustainability Reporting Standards (ESRS).  Syftet med rapporten är att identifiera klimatrelaterade risker som fastighetsbolag, med fokus på samhällsfastigheter, står inför samt att belysa de ekonomiska konsekvenserna av dessa risker. Vidare syftar rapporten till att bidra till utvecklingen av metoder för löpande hantering av klimatrisker, inklusive prioritering och åtgärdsplanering, samt att undersöka hur fastighetsbolag kan integrera klimatanpassning i linje med ESRS. Utvecklingen av modellen för klimat- och sårbarhetsanalyser baseras på tidigare analyser utförda av olika aktörer samt anpassning till ESRS. Semi-strukturerade intervjuer har genomförts med branschaktörer för att få en inblick i hur arbetet med klimatanpassning av fastigheter pågår och dess finansiella påverkan. För att undersöka hur marknadsvärdet kan påverkas av förebyggande klimatanpassningsåtgärder jämfört med kostnader efter en klimathändelse, genomfördes en kassaflödesanalys (Discounted Cashflow Analysis).  En 5-stegsmodell har utvecklats som inkluderar: kartläggning av fastighetsbeståndet, identifiering av klimatrelaterade risker, riskanalys och fastighetsspecifika egenskaper, riskbedömning samt implementering av klimatanpassningsåtgärder. Investeringar i klimatanpassningsåtgärder är billigare i längden än att inte klimatanpassa, eftersom kostnaderna för skador ofta är mycket högre och påverkar fastighetsvärdet mer negativt. Arbetet med klimatanpassning är en pågående process, och hållbarhetsrapportering enligt CSRD är komplicerat. Försäkringsbolag ersätter endast skador som klassas som ” plötsliga och oförutsedda”. Detta innebär att fastigheter behöver klimatanpassas för att vara kunna försäkras. Utan försäkringsskydd blir det dessutom svårt att få banklån, då fastigheter ofta används som säkerhet.
497

Impact of climate change on fresh water resources of Elliot town in the Eastern Cape

Ndlela, Bekithemba 11 1900 (has links)
Climate change and variability have great impact on the hydrological cycle and consequently on the availability of water resources. Variations in temperature and precipitation trends that are occurring are a consequent of the increase in the concentrations of greenhouse gases, which are subsequently affecting the hydrological cycle. This in turn affects water quantity and quality, which is essential for agriculture, domestic and industrial uses. This study, done in Elliot Town and the surrounding areas of Sakhisizwe Municipality in the Eastern Cape Province of South Africa, evaluates how climate change and variability is affecting water availability and its quality in the town. The impact climate change and variability on agricultural production is also assessed. Remote Sensing, Geographic Information Systems (GIS), databases and some statistical packages have been used to collect, analyse and create spatial maps used to derive concrete conclusions. The methods used aided in spatially analysing the changes in temperature and rainfall along the years and make a comparative analysis. The study has shown that the spatial changes in the amount, intensity and frequency of rainfall affects the magnitude and frequency of stream flows; consequently, increasing the intensity of floods and droughts that have been recurring in the last few decades. The municipality is more affected by climate variability than change, and the resultant extreme climate events are affecting the water resources resulting in domestic water cuts, poor water quality and low agriculture productivity. This study recommends the importance of an awareness campaigns on climate change and variability and their effect directed towards the community, especially on novel water harvesting technologies. The study also highlights the importance of a robust early warning system to prepare the community in case of a climate shock, which is an area that needs further research. / Environmental Sciences
498

Évolution du trait de côte, bilans sédimentaires et évaluation des zones à risques sur le littoral du Nord-Pas-de-Calais : analyse multi-échelles par LiDAR aéroporté / Shoreline evolution, sediment budget and assessment of areas at risk from coastal hazards on the coast of Nord-Pas-de-Calais : a multi-scale analysis using airborne topographic LiDAR

Crapoulet, Adrien 02 September 2015 (has links)
Les plages sableuses et les dunes côtuères occupent encore de nos jours une place importante dans la zone côtière du Nord-Pas-de-Calais. Ces accumulations sableuses, qui sont parfois le seul rempart protégeant les zones basses de la plaine côtière des submersions marines, sont des milieux particulièrement vulnérables dans le contexte actuel de l'élévation du niveau de la mer associée au changement climatique. Les objectifs principaux de la thèse étaient d'analyser les variations du trait de côte et du bilan sédimentaire à l'échelle régionale, d'apprécier le rôle des variations du volume sédimentaire sur la stabilité de la ligne de rivage, et d'évaluer les zones les plus menacées par les risques littoraux dans un avenir proche, de travail reposant en grande partie sur l'utilisation de données topographiques acquises par LiDAR aéroporté entre 2008 et 2014 ainsi que de photographies aériennes de 1963 à 2009. L'analyse de l'évolution du trait de côte a montré des évolutions contrastées, que ce soit spatialement ou temporellement. En effet, plusieurs portions de littoral ont connu une propagation du trait de côte à long terme, comme à court terme, tandis que d'autres sites ont subi un très fort recul à l'échelle de plusieurs décennies, mais aussi ces dernières années. La comparaison entre l'évolution du trait de côte et le volume initial du haut de plage en 2008, a montré que les reculs les plus importants se sont essentiellement produits dans les secteurs où l'on pouvait observer une absence de haut de plage à marée haute. Sur plusieurs sites, nos résultats suggèrent également qu'à partir d'un volume seuil de sédiments sur le haut de plage, le trait de côte est stable ou montre une tendance à la propagation vers le large. La cartographie de l'aléa de submersion marine à l'horizon 2050, prenant en compte la hausse du niveau marin liée au changement climatique, a montré clairement des franchissements du cordon dunaire sur plusieurs sites. Cette cartographie étant établie sur les données topographiques les plus récentes, à savoir décembre 2013 et janvier 2014, ces submersions potentiells ont une forte probabilité de se produire bien plus tôt que l'année 2050 en raison des forts taux d'érosion constatés sur certains massifs dunaires. Le calcul des bilans sédimentaires de l'ensemble du littoral régional, a montré, dans l'ensemble, une tendance à l'accrétion. Cette accrétion est d'autant plus significative pour le haut de plage et les dunes côtières, hormis pour quelques sites qui connaissent un grave déficit sédimentaire (particulièrement dans la baie de Wissant et sur la rive nord de la baie de l'Authie). Ces résultats suggèrent que la côte du Nord-Pas-de-Calais ne se trouve pas dans une situation de pénurie sédimentaire mais connaitrait plutôt une accumulation sur la majeure partie de son linéaire côtier. / Sandy beaches and coastal dunes still represent a significant portion of the coastal of Nord-Pas-de-Calais, northern France. These sandy accumulation landforms, which sometimes constitute the only defense protecting low-lying coastal areas from coastal flooding, are particularly vulnerable to sea level rise associated with climate change. The main objectives of the thesis were to analyze shoreline change and coastal sediment budget at the regional scale, to assess the role of changes in sediment volume on shoreline stability,and to evaluate areas at risk from coastal hazards in the near future, using airborne topographic LiDAR data collected between 2008 and 2014 and aerial photographs from 1963 to 2009. Analyses of shoreline change revealed spatially as well as temporally variables evolutions.Seaward shoreline progradation occured along several stretches of coastline at multidecadal and short times-scales, while significant coastal retreat took place at other sites during the same time periods. The comparison between coastline evolution and the initial volume of the upper beach in 2008 showed that the higher retreat rates were mainly observed in areas where the upper beach was lacking at high tide. Our results also suggest that there is a sediment volume threshold on the upper beach at each site above which the coastline is stable or progrades seaward. Mapping of areas at risk of marine flooding in 2050, taking into account a projection of sea level rise due to climate change, clearly shows that the submersion of coastal dunes would take place at several sites during storm-induced high water level events. The mapping of these areas at risk being based on topographic data collected in December 2013 and January 2014, coastal flooding is very likely to occur much earlier than 2050 at several sites, however, where very high rates of coastal retreat result in severe erosion of the coastal dunes. The calculation of sediment budget based on the repetitive LiDAR surveys shows that, overall, sediment accretion predominates over the entire regional coastal zone. This accretion is particularly significant for the upper beach and coastal dunes, except for a few sites that are characterized by a strong sediment deficit (particularly Wissant bay and the Northern shore of the Authie estuary). These results suggest that the coastal zone of Northern France does not experience sediment shortage, but is rather dominated by sediment storage in the backshore of the sand beaches
499

Metodologia para tomadas de decisão no âmbito de riscos sócio-ambientais em áreas urbanas: desmoronamentos e enchentes em assentamentos precários na bacia do Córrego Cabuçu de Baixo - SP. / Methodology for decision taken in the field of socio-environmental risks at urban areas: landslides and flooding in poor settlements on drainage basin of Cabuçu river -SP - Brazil.

Marino, Tiago Badre 29 May 2008 (has links)
De acordo com levantamento realizado pelo Instituto de Pesquisas Tecnológicas do Estado de São Paulo - IPT, os acidentes graves relacionados com deslizamentos atingem de forma recorrente um número relativamente pequeno dos 5.563 municípios brasileiros, girando em torno de 150 os que tiveram vítimas fatais nos últimos 17 anos. Os municípios mais vulneráveis localizam-se nos estados de São Paulo, Rio de Janeiro, Minas Gerais, Santa Catarina, Pernambuco, Alagoas, Bahia e Espírito Santo, localidades, na maioria dos casos, habitadas por pessoas de baixa renda, tornando-se, por conseguinte, expostas a catástrofes ambientais constantes (inundações devido ao assoreamento dos rios e erosão dos solos, os incêndios causados por instalações elétricas problemáticas, deslizamentos de terras, causadas por encostas irregulares e descalçamentos, entre outros). A Bacia Hidrográfica do Córrego Cabuçu de Baixo é um típico exemplo do que aconteceu em muitas cidades brasileiras. É uma bacia em acelerado processo de urbanização, mas ainda em condições para o controle, se bem administrada pelos seus gestores. Este trabalho objetiva a criação de mapeamentos que retratem avaliação positiva das condições ambientais (que pode ser chamado de \"potencial\") ou negativa (genericamente chamados de \"risco\" ambiental). Estes mapeamentos, de alto valor agregado por se originarem, via de regra, de discussões e concordâncias entre profissionais das diferentes modalidades da pesquisa ambiental - geógrafos, geólogos, biólogos, arquitetos e engenheiros, em geral - passam a constituir um valioso acervo de conhecimentos específicos da área estudada; a combinação das avaliações de riscos com o uso atual da terra, a fim de verificar possíveis áreas críticas, ou seja, assentamentos localizados em áreas mapeadas sob iminente risco de ocorrência de inundações e desmoronamentos; o levantamento das áreas indicadas para a transposição dos assentamentos localizados em áreas críticas. Todos os procedimentos computacionais realizados foram conduzidos pela metodologia de Análise Ambiental, utilizando o sistema VISTA/SAGA/UFRJ para processamento dos mapeamentos, obtenção e validação resultados. O resultado final das avaliações ambientais realizadas produz um mapa classificado com notas entre zero e dez, onde as notas mais baixas são atribuídas às localidades mapeadas com baixo risco de ocorrências de enchentes e desmoronamentos. De forma análoga, classes com maiores notas representam localidades com ocorrência de assentamentos precários sob risco iminente de inundações ou deslizamentos de terra e desmoronamentos. Estes mapas são denominados como \"Áreas Críticas\". Também são conduzidas análises para o mapeamento de áreas indicadas para transposições de localidades situadas em áreas críticas. A sobreposição destes dois últimos mapas aponta as localidades indicadas para transposições de assentamentos sob risco iminente dos eventos analisados. Finalmente, em áreas onde ocorram assentamentos precários sob alto risco de inundações e deslizamentos, sem indicações próximas para transposições (áreas favoráveis à habitação), sugere-se a realização de investimentos em infra-estrutura (ex. Programa Favela-bairro) destes locais, a fim de evitar impactos econômicos e sociais para as famílias afetadas por este processo. Assinaturas espaciais também são realizadas a fim de quantificar as áreas de riscos mapeadas. Uma vez realizados estes estudos, os conhecimentos adquiridos, pelo uso do Geoprocessamento, sobre a realidade ambiental urbana e problemática da Bacia do Córrego Cabuçu de Baixo podem ser extrapolados, com as devidas precauções, para inúmeras outras áreas urbanas que possuam características semelhantes e enfrentam os mesmos problemas. / According to studies conducted by the Institute for Technological Research of the State of Sao Paulo - IPT, major accidents related landslides hit so applicant a relatively small number of 5,563 brazilian councils, turning around of 150 who had human lives losses in the last 17 years. The most vulnerable councils are located in the states of São Paulo, Rio de Janeiro, Minas Gerais, Santa Catarina, Pernambuco, Alagoas, Bahia and Espirito Santo. These locations, most cases, inhabited by low conditions people, become, therefore, exposed to constant environmental disasters (floods due to the silting of rivers and soil erosion, fires caused by problematic electrical installations, landslides, caused by irregular slopes, among others). The drainage basin of Cabuçu de Baixo river is a typical example of what happened in many Brazilian cities. It is a basin in accelerated process of urbanization, but also in a position to control, although administered by their managers. This study aims to create mappings facing positive assessment of environmental conditions (which can be called a \"potential\") or negative (generically called environmental \"risk\"). These maps are generated from professional discussions and agreement between the many kinds of researches - geographers, geologists, biologists, architects and engineers in general - are to be a valuable collection of expertise of the studied area, the combination of risk assessments to the current land using in order to check on critical areas, ie settlements located in areas mapped with imminent risk of flooding and landslides; survey of the areas indicated for the transposition of the settlements located in critical areas. All procedures performed are conducted by the computational methodology of Environmental Analysis, using the GIS VISTA/SAGA/UFRJ, processing mappings, obtaining and validating results. The final result of environmental evaluation conducted produces a \"Critical Areas\" map, presenting classified notes between zero and ten, where lower notes are assigned to locations mapped with low risk of occurrence of floods and landslides. Similarly, classes with higher notes represent locations where precarious settlements are mapped under imminent risk of flooding, landslides and landslides. Analyses pointing transposition areas, according to physical factors are also conducted, aiming to locate settlements under critic areas. The overlay of these both maps point transpositions indicated for settlements located under imminent risk areas. Finally, in areas where precarious settlements occurs under high floods and landslides risks, without near indications for transpositions (favorable areas for housing), it is suggested to make investments in infrastructure into these places, in order to maintain the \"roots\" of these affected families by this process. Spatial signatures are also conducted in order to quantify the risk areas mapped. Once these studies conducted, knowledge gain by the use of Geoprocessing, applied to the reality of urban environmental problems in the Drainage Basin Cabuçu, these can be extrapolated, with the necessary precautions, to other urban areas that presents similar characteristics and faces the same problems.
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Os impactos ambientais no meio físico: erosão e assoreamento na bacia hidrográfica do rio Taquari, MS, em decorrência da pecuária / The impacts on physical environmental: erosion and silting in the Taquari river watershed, MS, caused by cattle raising activity

Abdon, Myrian de Moura 26 March 2004 (has links)
O aumento da inundação em áreas do baixo curso do rio Taquari, no Pantanal do estado do Mato Grosso do Sul, tem transformado a pecuária desta região numa atividade com baixa rentabilidade, à medida que extensas áreas de campo passaram a ser inundadas vários meses durante o ano a partir da década de 70. A pecuária realizada em campos naturais de regiões úmidas do Pantanal indica que há necessidade de se investigar metodologias apropriadas para avaliação de impacto ambiental, que abordem impactos diretos, indiretos, cumulativos e processos do meio físico que alteram, de maneira prejudicial, o meio ambiente. Supõe-se que a inundação na planície do rio Taquari esteja relacionada com a ocupação antrópica nas áreas de planalto da bacia do rio Taquari. O presente trabalho tem por objetivo avaliar os impactos ambientais na planície de inundação do baixo curso do Taquari, decorrentes da ocupação antrópica da bacia hidrográfica do rio Taquari em sua totalidade, considerando os impactos ambientais causados pela pecuária à medida que se configura como principal atividade econômica da bacia bem como os processos erosivos e de assoreamento no quadro atual do regime de inundações. As etapas de caracterização da área, de análise dos impactos e as propostas de ações mitigadoras, previstas num Estudo de Impacto Ambiental, foram aqui analisadas. Foram utilizadas informações sobre as características do meio físico, biótico e socioeconômico, selecionadas a partir do levantamento dos dados existentes com recorte efetuado para a bacia hidrográfica do rio Taquari. Na maior parte dos temas, este foi um processo de levantamento, ordenamento e recuperação de informações, na escala original de 1:250.000, do Plano de Conservação da Bacia do Alto Paraguai-PCBAP, gerenciado no SPRING. Foram também realizadas viagens de campo para a complementação dos dados e para o levantamento de atividades antrópicas com verificações \"in loco\" da ocorrência de impacto ambiental. A maioria dos dados socioeconômicos compilados para o presente trabalho teve por base os censos agropecuários e demográficos realizados pelo IBGE. Os resultados obtidos demonstram que os impactos ambientais decorrentes da pecuária no planalto interferem no regime de inundação na planície da bacia, o que só foi possível de ser identificado a partir de análises integradas em toda a bacia hidrográfica do rio Taquari. Verificou-se que os métodos de EIA são adequados para identificar os impactos diretos decorrentes da pecuária, mas não são adequados para identificar os processos e seus efeitos cumulativos na extensão da bacia hidrográfica do rio Taquari. Além disto, a abordagem da avaliação ambiental estratégica, como procedimento para análise ambiental em políticas, planos e programas, mostra-se adequada para as análises na BHRT à medida que está centralizada nos efeitos do ambiente sobre as necessidades e oportunidades de desenvolvimento. Contudo, somente a recuperação de danos ambientais, o controle das origens dos impactos no ambiente e um sistema de gestão consciente de seus compromissos podem levar, juntamente com a melhora dos procedimentos técnicos e administrativos para análises ambientais, à uma maior proximidade da sustentabilidade ambiental na BHRT. / The increase of flooding in the low course areas of Taquari river in the Pantanal - Mato Grosso do Sul state, has been transforming the cattle raising activity to a low profit activity in the region, when that extensive areas of pasture started to be flooded throughout several months a year from the 1970s. Since these areas are located in the Pantanal region where cattle raising activity is carried on in natural pasture it is necessary to investigate suitable methodologies for evaluation of the ambiental impact, approaching direct, indirect and cummulative impact as well as the processes that change, in a harmful way the environment. The flooding in the floodplain in Taquari river is supposed to be related to the anthropic ocupation in the upland areas of the Taquari river watershed. This work aims to evaluate the environmental impact caused by the anthropic ocupation, the cattle raising activity in the basin and the erosion and silting process in the flood plain of the Taquari river low course. The steps for the area characterization, the analysis of the impact and proposals viewing to diminish the problem, projected in an EIA (Environmental Impact Study), were also considered here. Information on the physical, biologic and socio-economic environment, selected from pre existent data survey, carried on for the Taquari river watershed (BHRT) were used here. For most of the themes, this was a process of surveying and recovering information in the original scale of 1:250.000 from the PCBAP managed in the SPRING GIS model. Field work to complement the existent data to survey the environmental impact of anthropic activities were also carried on. Most of socio-economic data used here were based on the cattle raising activity and demographic census data from IBGE. The results show that the environmental impact caused by cattle raising in the upland interferes in the flooding system in the watershed flood plain, and this fact could only be identified from the integrated analysis of the whole Taquari river watershed. It was observed that the EIA methods are suitable to identify the direct impact caused by the cattle raising activity, but they are not suitable to identify the process and its cummulative effects along the Taquari river watershed. Moreover, it was observed that the approach of the Strategic Environmental Assessment (SEA) as a procedure for environmental analysis in the policies, plans and programs is suitable for the analysis in the BHRT when it is centralized in the effects of environment on the necessities and opportunities of development. However, only the recovering of ambiental damage, the control of the effects caused by impacts on the environment and a system of conscient management can lead to an improvement in the technic and administrative procedures for a really possible ambiental sustentability in the BHRT.

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