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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

[en] COMPARASION BETWEEN LAND USE AND LAND COVER DATA FROM TERRACLASS AND THE AGRICULTURAL CENSUS IN THE MUNICIPALITY OF LÁBREA - AM / [pt] COMPARAÇÃO ENTRE OS DADOS DE USO E COBERTURA DO SOLO DO TERRACLASS E O CENSO AGROPECUÁRIO NO MUNICÍPIO DE LÁBREA - AM

PRISCILA RIBEIRO DE CARVALHO DE MEDEIROS 06 March 2020 (has links)
[pt] Este trabalho propõe a comparação entre os dados do TerraClass 2004 e o Censo Agropecuário 2006 para analisar o uso de um na ausência do outro, para compreender o uso e cobertura do solo pela agropecuária na área de estudo. Através dos dados de uso e cobertura do solo do TerraClass 2004 e do Censo Agropecuário 2006, foi feita uma análise das áreas de cada classe que se enquadram como atividade agropecuária e uma comparação dessas áreas nas duas classificações. A análise utilizou o Sistema de Informação Geográfica (SIG) com imagens de satélite Landsat/TM 5 para auxiliar na análise visual qualitativa das classes e obter respostas sobre o uso e ocupação do solo no município de Lábrea. Foram escolhidos 16 setores censitários sobre os quais se tinha dados de classes referentes a agropecuária, analisando e percebendo uma variação percentual considerável em relação as duas classificações. A metodologia de comparação serviu para verificar que os métodos de aquisição dos dados do TerraClass 2004 e do Censo Agropecuário 2006 apresentam diferenças consideráveis nos resultados. Foram encontradas na classificação do TerraClass, através da análise qualitativa utilizando a imagem de satélite, dúvidas quanto a algumas classes sem vegetação, mas que não foram classificadas como atividade agropecuária, como desflorestamento, e essas consideradas duvidosas. Por fim, o presente trabalho conclui que não é adequado utilizar os dados do TerraClass na ausência do Censo Agropecuário, ou vice-versa, tendo em vista a disparidade encontrada em alguns dos setores censitários analisados. Sugere-se para trabalhos futuros um estudo específico para saber as causas das áreas desmatadas das classes consideradas duvidosas. / [en] This work proposes comparing data provided by 2004 s TerraClass and 2006 s Agribusiness Census, analyzing the validity of using one absent the other to comprehend the land cover in relation to said business within the studied area. The areas of the classes related to agribusiness were compared through the land cover reported in each classification. This analysis took place in a GIS environment with the use of Landsat/TM 5 to aid in the visual qualitative comparison of the data. The region of interest was the municipality of the Labrea district in the southern region of the Amazonas state. Sixteen census sector that showed agribusiness information were chose for the comparison of the percentages of area attributed to that business type. The variation of such areas was noteworthy and it was deemed that one should not use the two sources compared interchangeably as the information does not match. Moreover, some classes of the TerraClass classification stood out and regarded as uncertain – such as generic deflorestation and not forest – as, knowing the regions historical occupation and recent expansion of agribusiness, one would suspect that those are indeed related to the agents studied in this work.
142

Quantifying numerical weather and surface model sensitivity to land use and land cover changes

Lotfi, Hossein 09 August 2022 (has links)
Land surfaces have changed as a result of human and natural processes, such asdeforestation, urbanization, desertification and natural disasters like wildfires. Land use and landcover change impacts local and regional climates through various bio geophysical processes acrossmany time scales. More realistic representation of land surface parameters within the land surfacemodels are essential to for climate models to accurately simulate the effects of past, current andfuture land surface processes. In this study, we evaluated the sensitivity and accuracy of theWeather Research and Forecasting (WRF) model though the default MODIS land cover data andannually updated land cover data over southeast of United States. Findings of this study indicatedthat the land surface fluxes, and moisture simulations are more sensitive to the surfacecharacteristics over the southeast US. Consequently, we evaluated the WRF temperature andprecipitation simulations with more accurate observations of land surface parameters over thestudy area. We evaluate the model performance for the default and updated land cover simulationsagainst observational datasets. Results of the study showed that updating land cover resulted insubstantial variations in surface heat fluxes and moisture balances. Despite updated land use andland cover data provided more representative land surface characteristics, the WRF simulated 2- m temperature and precipitation did not improved due to use of updated land cover data. Further,we conducted machine learning experiments to post-process the Noah-MP land surface modelsimulations to determine if post processing the model outputs can improve the land surfaceparameters. The results indicate that the Noah-MP simulations using machine learning remarkablyimproved simulation accuracy and gradient boosting, and random forest model had smaller meanerror bias values and larger coefficient of determination over the majority of stations. Moreover,the findings of the current study showed that the accuracy of surface heat flux simulations byNoah-MP are influenced by land cover and vegetation type.
143

Proceedings of the East-Africa Regional Alumni Capacity Building and Networking Seminar

Auch, Eckhard 24 April 2023 (has links)
This volume contains the abstracts of participants of the seminar. / PROGRAM: The seminar consists both of scientific exchange and social events. Keynote speeches on integrated natural resources management, planning and landscape governance make up an essential part of the seminar, complemented by presentations of posters from the participants, an excursion to a landscape project and a role play with a landscape planning exercises. To underpin theory with valuable local practical experience, an exchange with practitioners from forestry and water management in the wider fringe of Kampala will take place. The seminar is designed to encourage interaction among participants and to facilitate the sharing and discussion of individual experiences and perspectives on the various topics. By this learning and generating insights shall be enabled, for upgrading the competencies of the participants and for improving strategies for natural resource management. Kindly find the detailed program schedule on the following pages.
144

Land Use, Freshwater Flows and Ecosystem Services in an Era of Global Change

Gordon, Line January 2003 (has links)
<p>The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. Although of great significance, this thesis shows that such a focus will not be sufficient for coping with freshwater related social-ecological vulnerability. The thesis illustrates that the terrestrial component of the hydrological cycle, reflected in vapour flows (or evapotranspiration), serves multiple functions in the human life-support system. A broader understanding of the interactions between terrestrial systems and freshwater flows is particularly important in light of present widespread land cover change in terrestrial ecosystems. </p><p>The water vapour flows from continental ecosystems were quantified at a global scale in Paper I of the thesis. It was estimated that in order to sustain the majority of global terrestrial ecosystem services on which humanity depends, an annual water vapour flow of 63 000 km3/yr is needed, including 6800 km3/yr for crop production. In comparison, the annual human withdrawal of liquid water amounts to roughly 4000 km3/yr. A potential conflict between freshwater for future food production and for terrestrial ecosystem services was identified. </p><p>Human redistribution of water vapour flows as a consequence of long-term land cover change was addressed at both continental (Australia) (Paper II) and global scales (Paper III). It was estimated that the annual vapour flow had decreased by 10% in Australia during the last 200 years. This is due to a decrease in woody vegetation for agricultural production. The reduction in vapour flows has caused severe problems with salinity of soils and rivers. The human-induced alteration of vapour flows was estimated at more than 15 times the volume of human-induced change in liquid water (Paper II). </p>
145

Vetores de mudança na multifuncionalidade da paisagem costeira do Litoral Norte de São Paulo. /

Pierri-Daunt, Ana Beatriz January 2019 (has links)
Orientador: Thiago Sanna Freire Silva / Resumo: As paisagens são a expressão da interação dinâmica entre processos naturais e atividades humanas. A região do Litoral Norte do Estado de São Paulo apresenta uma grande diversidade de fitofisionomias do bioma Mata Atlântica, e um rico patrimônio material e imaterial, em função da histórica interação do homem com a natureza. São inúmeros os vetores que agem simultaneamente sobre essa paisagem, resultando em efeitos cumulativos que transformam sua multifuncionalidade e multidimensionalidade. Este estudo objetivou a compreensão dos vetores de mudanças na paisagem do Litoral Norte do Estado de São Paulo. A transformação histórica da paisagem na área de estudo foi investigada buscando compreender a modificações dos cenários paisagísticos na sua integridade desde o início da colonização europeia na região de estudo. Através desta revisão histórica, demonstramos que a política econômica impulsionou investimentos em instalações tecnológicas e de acesso a região, que influenciaram no aumento das taxas de crescimento populacional, resultando num rápido crescimento das áreas urbanas após meados do século XX. O segundo capítulo quantificou as mudanças físicas da paisagem, através de séries históricas de imagens da série de satélites Landsat, utilizando o algoritmo Random Forests para classificação supervisionada do uso e cobertura da terra. Pudemos então, demonstrar que a região apresenta tendência a uma dicotomia no uso da terra, entre o uso urbano e a conservação ambiental. Entre 1985 e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Landscapes are an expression of the dynamic interaction between natural environments and human activities. The Northern Coast of São Paulo State has a high diversity of Atlantic Forest vegetation types, and the Serra do Mar mountain range has a rich material and immaterial heritage due to ancient human-nature interactions. There are several different driving forces of change acting together over these landscapes, resulting in a cumulative effect over time. Our study sought to understand the causes and consequences of landscape change in the Northern Coast of São Paulo state, from 1985 to present. We described the land use history and landscape changes since the Europeans arrived in the region, during the XVI century. We identified that national economic policies and interests have led to investment in improved access and technological development, which in turn influenced migration to the region and resulted in fast urban expansion. In the second chapter, we have shown that land use change in the Northern Coast of São Paulo poses a dichotomy between two main land cover change trajectories over 30 years: forest persistence and fast urban growth. We found only 100 km² (8%) of forest disturbance within the State Parks, while dense urban settlements grew 167% outside the park, replacing mainly rural land uses. To identify and understand the driving forces of change in the region, we used Partial Least Squares - Path Modelling to model the relation between driving forces and lands... (Complete abstract click electronic access below) / Doutor
146

CAPACIDADE DE USO DA TERRA E PERDA DE SOLO EM UMA PROPRIEDADE REPRESENTATIVA NA BACIA HIDROGRÁFICA DO RIO DO ATALHO, CRUZ MACHADO – PR.

Marinheski, Vanderlei 21 November 2011 (has links)
Made available in DSpace on 2017-07-21T18:13:49Z (GMT). No. of bitstreams: 1 Vanderlei Marinheski.pdf: 3407638 bytes, checksum: c104e9f29ac3ce677f207d687852e310 (MD5) Previous issue date: 2011-11-21 / This study sought to evaluate the contribution of different sources producing in sediment on a representative property in river basin of the shortcut, Cruz Machado, PR, and through utility survey of the physical environment in the basin was proposed map a capacity of land use to basin and a in specific for property in representative. The property has a representative system of family farms with low technological level and with the use of rudimentary tools (sickle, hoe use and animals to till the soil), relief is characterized by the constant presence of blocks and boulders of igneous rocks, beyond the steep slopes of the slopes, features that predominate in other properties of the basin and the region as a whole. To measure the erosion were installed plots with erosion pins in a crop of corn, mate, pasture, an area near the house and four snippets of rural roads inside the property, and two stretches of road outside a property on the road general of the basin and the other with access from the house of a farmer in general road, these two have paved with gravel. With the monitoring of parcels and profiles of roads for a year, there were levels of soil removal at each pin or mediated profile road. The results indicate the removal of soil above the tolerance levels for soil characteristics, especially on roads and crop areas. The maps of land use capacity of the basin and representative of the property indicate that more than half of the areas have no aptitude for agriculture and should be used for permanent crops or preserving the flora and fauna.. / O presente estudo buscou avaliar a contribuição das diferentes fontes produtoras de sedimentos em uma propriedade representativa na Bacia do Rio do Atalho em Cruz Machado no Paraná. Através de levantamento utilitário do meio físico na bacia, foi proposto um mapa de capacidade de uso da terra para a bacia e um em específico para a propriedade representativa. Esta propriedade possui um sistema de agricultura familiar com baixo nível tecnológico, com uso de ferramentas rudimentares (foice, enxada e o uso de animais para cultivar o solo). O relevo é caracterizado pela constante presença de blocos e matacões de rochas ígneas, além das declividades acentuadas das vertentes, características que predominam em outras propriedades da bacia e região. Para mensuração da erosão foram instaladas parcelas com pinos de erosão em áreas de lavoura com milho, erva-mate, pastagem, quintal e 4 trechos de estradas rurais internas da propriedade, além de 2 trechos de estrada (pavimentadas com cascalho), fora da propriedade, um na estrada geral da bacia e outro que liga a casa de um agricultor à estrada geral. Com o monitoramento das parcelas e trechos de estradas durante um ano, verificaram-se os níveis de remoção de solo em cada pino ou mediada de perfil de estrada. Os resultados indicaram a remoção acima dos níveis de tolerância para as características do solo, principalmente nas estradas e áreas de cultivo. Os mapas de capacidade de uso da terra da bacia e da propriedade representativa apontam que mais da metade das áreas, não apresentam aptidão para agricultura e devem ser usadas para culturas permanentes ou preservação da flora e fauna.
147

Modélisation des relations entre occupation - usage du sol et distribution spatiale du paludisme par télédétection optique et radar : application à un environnement en évolution : région transfrontalière Guyane Française – Brésil / Modeling the relationships between land cover, land use and malaria spatial distribution using optical and SAR remote sensing : application to a changing environment : French Guiana - Brazil cross-border area

Li, Zhichao 08 December 2016 (has links)
Le paludisme est un des maladies vectorielles les plus communes qui est situé principalement dans les régions tropicales. La zone étudiée est la région transfrontière Guyane française-Brésil. Le niveau et la dynamique intra-annuelle de la transmission y sont variables, avec un taux d’incidence qui est relativement élevé dans l’Amérique du Sud. Les facteurs environnementaux, en particulier l'occupation et l'usage du sol, influent significativement sur la présence, la densité et la distribution spatiale des moustiques du genre Anophèles, vecteurs de la maladie. Les données sur l'environnement, la population et les systèmes de santé sont rarement comparables de part et d’autre de la frontière Guyane-Brésil, excluant une vision bilatérale homogène. La télédétection permet de caractériser spatialement l’environnement de manière quasi continue et complète. L’objectif de ce travail est de caractériser par télédétection des milieux favorables au développement des vecteurs et les interactions hommes-vecteurs pour la zone transfrontalière Guyane-Brésil. Un indicateur spatialisé d’aléa de transmission du paludisme a été développé à l’échelle locale. Il permet de spatialiser la contribution de l'interaction entre milieux forestiers et non-forestiers sur la transmission du paludisme. Ce modèle a été mis en œuvre à l’échelle de la région amazonienne. Cet indice permet de quantifier et d’expliquer l’influence du paysage dans les interrelations homme - vecteurs adultes. L’identification des gîtes larvaires potentiels a été testée à une échelle régionale, à partir de la fusion d’images satellites optiques et radar, afin de mettre en évidence la distribution spatiale de zones humides pérennes et de grandes tailles (lacs, rivières, étangs, etc.) et les interfaces avec les milieux urbaines et forestiers. La distribution et la densité des vecteurs sont affectées par les propriétés physiques et chimiques des gîtes larvaires potentiels qui sont liées à la typologie des sols. Un modèle conceptuel de l’évaluation des sols adapté à la zone amazonienne présente que les caractéristiques géomorphologiques (altitude, courbure, etc.) sont indicateurs de l’évolution des sols. Une typologie des sols a été réalisée à l’échelle régionale à partir de données altimétriques et de ce modèle conceptuel. Les méthodologies, les cartes d’occupation et d’usage du sol, les cartes d’aléa du paludisme mises en place dans le cadre de cette thèse seront intégrés à l’Observatoire transfrontalier (Guyane-Brésil) qui est en cours de création. Ce travail de thèse contribue ainsi à l’exploitation des nouvelles connaissances sur le mécanisme de transmission du paludisme qui peuvent être utilisées pour définir les nouvelles stratégies de prévention aux échelles locale et régionale. / Malaria remains one of the most common vector-borne diseases what is predominantly located in the tropics. The study area is the cross-border area between French Guiana and Brazil where the level and intra-annuel dynamic of malaria transmission are variable, with the incidence rates which are relatively high in South America. The environmental risk factors, in particular, land use and land cover, significantly influence the presence, density and spatial distribution of disease vectors, Anopheles mosquitoes. Environmental information, population data and health systems database are rarely comparable on both sides of the Guyana-Brazil border which exclude the homogeneous and bilateral vision. Remote sensing permits to spatially characterize the environment on both sides of the border in an almost continuous and complete manner. The objective of this study is to characterize the favorable environment for the development of vectors and the vector-human interaction in the cross-border area between French Guiana and Brazil using remote sensing. A spatial landscape-based hazard index of malaria transmission was developed at the local scale. Such index allows spatializing the contribution of interaction between forest and non-forest areas on malaria transmission which was then implemented in the entire Amazon region. It quantifies and explains the influence of landscape on the interaction between human population and adult vectors. The identification of potential breeding sites of vectors was tested on a regional scale using the optical and SAR fusion for highlighting the spatial distribution of perennial and large wetlands (lakes, rivers, ponds etc.) and the interfaces with urban and forest environments. The distribution of vectors’ density is affected by physical and chemical properties of potential breeding sites which are related to soil typology. A conceptual model of soil evolution adapted to the Amazon region presents that geomorphological characteristics (altitude, curvature, etc.) are indicators of soil evolution. A soil classification was realized at the regional scale using altimetry data and the conceptual model. The methods, land use and land cover and malaria hazard maps established in this thesis will be integrated in the Observatory Sentinel of cross-border which is being built. This study also contributes to the exploitation of new knowledge about malaria transmission mechanism which can be used to define novel prevention strategies at the local and regional scales.
148

Land Use, Freshwater Flows and Ecosystem Services in an Era of Global Change

Gordon, Line January 2003 (has links)
The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. Although of great significance, this thesis shows that such a focus will not be sufficient for coping with freshwater related social-ecological vulnerability. The thesis illustrates that the terrestrial component of the hydrological cycle, reflected in vapour flows (or evapotranspiration), serves multiple functions in the human life-support system. A broader understanding of the interactions between terrestrial systems and freshwater flows is particularly important in light of present widespread land cover change in terrestrial ecosystems. The water vapour flows from continental ecosystems were quantified at a global scale in Paper I of the thesis. It was estimated that in order to sustain the majority of global terrestrial ecosystem services on which humanity depends, an annual water vapour flow of 63 000 km3/yr is needed, including 6800 km3/yr for crop production. In comparison, the annual human withdrawal of liquid water amounts to roughly 4000 km3/yr. A potential conflict between freshwater for future food production and for terrestrial ecosystem services was identified. Human redistribution of water vapour flows as a consequence of long-term land cover change was addressed at both continental (Australia) (Paper II) and global scales (Paper III). It was estimated that the annual vapour flow had decreased by 10% in Australia during the last 200 years. This is due to a decrease in woody vegetation for agricultural production. The reduction in vapour flows has caused severe problems with salinity of soils and rivers. The human-induced alteration of vapour flows was estimated at more than 15 times the volume of human-induced change in liquid water (Paper II).
149

Žemės naudojimo valstybinė kontrolė: reglamentavimas ir vykdymas Širvintų savivaldybėje / Public land use control: regulation and inforcement in Širvintos municipality

Karneckienė, Jūratė 05 July 2011 (has links)
Žemė visais laikais buvo vertinama kaip visuotinė vertybė, kurios pagrindinė socialinė funkcija – tarnauti tautos gerovei. Bet kokia fizinė veikla keičia natūralią žemės būklę ir funkcijas, todėl atsižvelgiant į visuomeninių santykių, valstybės ekonomikos dinamikos ir raidos procesus, ypač svarbu, kad žemė būtų racionaliai ir efektyviai naudojama. Tai pagrindžia objektyviai nepaneigiamą pareigą valstybei nuosavybės į žemę, taip pat žemės valdymo ir naudojimo santykius reguliuoti taip, kad būtų suderinti visų žemės teisinių santykių subjektų interesai ir užtikrinta pagrindinė žemės funkcija. Žemės naudojimo valstybine kontrole būtent ir siekiama užtikrinti, kad valdant ir naudojant žemę, būtų laikomasi Lietuvos Respublikos žemės įstatymo bei kitų įstatymų, susijusių su žemės naudojimo priežiūra, taip pat apsaugoti valstybinės žemės nuosavybės teises. Žemės naudojimo valstybinė kontrolė - įstatymais ir kitais teisės aktais reglamentuotas žemės savininkų ir naudotojų veiklos priežiūros priemonių įgyvendinimo procesas, kuriuo siekiama užtikrinti tinkamą žemės ir gamtos išteklių naudojimą bei jų teisinę apsaugą, taip pat nustatyti nukrypimus nuo nustatytų reikalavimų ir užfiksuoti teisės aktų pažeidimus, bei pagal kompetenciją imtis įstatymų numatytų priemonių pažeidėjams nubausti. Už žemės naudojimo valstybinės kontrolės vykdymą atsakinga Nacionalinė žemės tarnyba prie Žemės ūkio ministerijos, tiesiogiai kontrolę vykdo teritoriniai žemėtvarkos skyriai. Baigiamajame darbe... [toliau žr. visą tekstą] / In all times the land was seen as universal value, which main social function is to serve for the welfare of people. Any physical activity has impact on the natural state and functions of land, that is why the rational and effective use of land is so important. Public land use control has to ensure that the land administrators and land users respect and comply the laws regulating the land use and to protect the stateland ownership. Public land use control is the process of land administrators and land users activity supervision, which is regulated by laws, which is intended to ensure proper land and natural resources usage and legal protection, also identify deviation from the requirements and fixate violations, and under jurisdiction take legal actions to punish offenders. The Nacional Land Service under the Ministry of Agriculture of the Republic of Lithuania and territorial Land divisions are responsable for the public land use control. The regulation and execution of public land use control in Širvintai municipality is rewieved and estimated in this thesis. There are literature source anglysis, comperative and assessment anglysis, and logical methods used in this final work. The laws regulating the land use control, the Nacional Land Service under the Ministry of Agriculture of the Republic of Lithuania, Širvintai land division documentation on public land use control is analized. It is found that the public land use control in Širvintai municipality, also as in the... [to full text]
150

Development of a flood-frequency model for the river basins of the Central Region of Malawi as a tool for engineering design and disaster preparedness in flood-prone areas

Laisi, Elton 02 1900 (has links)
Since 1971, a number of flood frequency models have been developed for river basins in Malawi for use in the design of hydraulic structures, but the varied nature of their results have most often given a dilemma to the design engineer due to differences in magnitudes of calculated floods for given return periods. All the known methods for flood frequency analysis developed in country so far have not used a homogeneity test for the river basins from which the hydrological data has been obtained. This study was thus conducted with a view to resolving this problem and hence improve the design of hydraulic structures such as culverts, bridges, water intake points for irrigation schemes, and flood protection dykes. In light of the above, during the course of this study the applicability of existing methods in the design of hydraulic structures was assessed. Also, the study investigated how land use and land cover change influence the frequency and magnitude of floods in the study area, and how their deleterious impacts on the socio-economic and natural environment in the river basins could be mitigated / Environmental Sciences / M. Sc. (Environmental Management)

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