1,720,969 research outputs found
Geotecnologias aplicadas à estimativa de perdas de solo por erosão hídrica na sub-bacia do Ribeirão das Perobas, Município de Santa Cruz do Rio Pardo-SP
No full textA erosão do solo constitui o principal fator de degradação das terras agrícolas. Ela é influenciada por fatores climáticos, pela suscetibilidade natural dos solos, características do relevo e intervenção antrópica através do uso, manejo do solo e das práticas conservacionistas, que podem acelerá-la ou reduzi-la. O objetivo deste trabalho é realizar uma estimativa de perda de solo por erosão hídrica na Sub-Bacia do Ribeirão das Perobas, localizada no município de Santa Cruz do Rio Pardo – SP, através da Equação Universal de Perda de Solo Revisada (RUSLE), utilizando ferramentas de Geoprocessamento e Sensoriamento Remoto. Foi elaborado o mapa detalhado de solos da sub-bacia, a partir do qual se determinou a erodibilidade, a tolerância de perda de solo e se efetuou a classificação das terras no sistema de capacidade de uso. Os mapas de erosividade da chuva, fator topográfico, uso e manejo do solo e práticas conservacionistas foram elaborados em ambiente de Sistema de Informação Geográfica (SIG) a partir de dados do programa netErosividade SP, do modelo digital de elevação do terreno e de imagens de satélite, respectivamente. Foram determinados o Potencial Natural de Erosão, a perda de solo (cenário atual), a Capacidade de uso-manejo permissível, o Risco de Erosão Simulado e a Expectativa de Erosão da sub-bacia.Dois cenários de perda de solos foram simulados: 1) adequação do uso, manejo e práticas conservacionistas à capacidade de uso, e 2) áreas agricultáveis ocupadas por cana-de-açúcar sem manejo e plantio em nível. A estimativa de perda de solo através da RUSLE evidenciou que a erosão resulta da interação de fatores dos meios físico e antrópico, mas sofreu maior influência do fator C (uso e manejo do solo). O mapa de capacidade de uso-manejo permissível, associado à capacidade de uso da terra...Soil erosion is the main factor of agricultural land degradation. It is influenced by climatic factors, natural susceptibility of soils, topography characteristics and by human intervention, through land cover, management and support practices, which can increase it or reduce it. This work aims to perform an estimation of soil loss by water erosion in Ribeirão das Perobas Sub-basin, located in Santa Cruz do Rio Pardo, São Paulo state, through Revised Universal Soil Loss Equation (RUSLE), using GIS and Remote Sensing tools. It was elaborated the detailed soil map of the sub-basin, from which were determined the erodibility, soil loss tolerance and it was performed the land classification into the land use capacity system. Rainfall erosivity, topographic factor, cover-management and support practices maps were elaborated in GIS (Geographical Information System), using the netErosividade SP program, the digital elevation model and the satellite images, respectively. The Natural Potential of Erosion, the soil loss (current scenario), the Permissible Land Cover-Management Capacity, the Simulated Erosion Risk and the Sub-basin Erosion Expectation were determined. Two soil loss scenarios were simulated: 1) adequacy of the cover-management and the support practices to the land use capacity, and 2) farming areas occupied by sugarcane crops without management and contour tillage. The soil loss estimation through RUSLE showed that erosion results from the interaction of natural and anthropogenic factors, but it suffered more influence of the C factor (soil cover and management). The Permissible Land Cover-Management map, associated with... (Complete abstract click electronic access below)Universidade Estadual Paulista (UNESP
Geotecnologias aplicadas à estimativa de perdas de solo por erosão hídrica na sub-bacia do Ribeirão das Perobas, Município de Santa Cruz do Rio Pardo-SP
No full textA erosão do solo constitui o principal fator de degradação das terras agrícolas. Ela é influenciada por fatores climáticos, pela suscetibilidade natural dos solos, características do relevo e intervenção antrópica através do uso, manejo do solo e das práticas conservacionistas, que podem acelerá-la ou reduzi-la. O objetivo deste trabalho é realizar uma estimativa de perda de solo por erosão hídrica na Sub-Bacia do Ribeirão das Perobas, localizada no município de Santa Cruz do Rio Pardo – SP, através da Equação Universal de Perda de Solo Revisada (RUSLE), utilizando ferramentas de Geoprocessamento e Sensoriamento Remoto. Foi elaborado o mapa detalhado de solos da sub-bacia, a partir do qual se determinou a erodibilidade, a tolerância de perda de solo e se efetuou a classificação das terras no sistema de capacidade de uso. Os mapas de erosividade da chuva, fator topográfico, uso e manejo do solo e práticas conservacionistas foram elaborados em ambiente de Sistema de Informação Geográfica (SIG) a partir de dados do programa netErosividade SP, do modelo digital de elevação do terreno e de imagens de satélite, respectivamente. Foram determinados o Potencial Natural de Erosão, a perda de solo (cenário atual), a Capacidade de uso-manejo permissível, o Risco de Erosão Simulado e a Expectativa de Erosão da sub-bacia.Dois cenários de perda de solos foram simulados: 1) adequação do uso, manejo e práticas conservacionistas à capacidade de uso, e 2) áreas agricultáveis ocupadas por cana-de-açúcar sem manejo e plantio em nível. A estimativa de perda de solo através da RUSLE evidenciou que a erosão resulta da interação de fatores dos meios físico e antrópico, mas sofreu maior influência do fator C (uso e manejo do solo). O mapa de capacidade de uso-manejo permissível, associado à capacidade de uso da terra...Soil erosion is the main factor of agricultural land degradation. It is influenced by climatic factors, natural susceptibility of soils, topography characteristics and by human intervention, through land cover, management and support practices, which can increase it or reduce it. This work aims to perform an estimation of soil loss by water erosion in Ribeirão das Perobas Sub-basin, located in Santa Cruz do Rio Pardo, São Paulo state, through Revised Universal Soil Loss Equation (RUSLE), using GIS and Remote Sensing tools. It was elaborated the detailed soil map of the sub-basin, from which were determined the erodibility, soil loss tolerance and it was performed the land classification into the land use capacity system. Rainfall erosivity, topographic factor, cover-management and support practices maps were elaborated in GIS (Geographical Information System), using the netErosividade SP program, the digital elevation model and the satellite images, respectively. The Natural Potential of Erosion, the soil loss (current scenario), the Permissible Land Cover-Management Capacity, the Simulated Erosion Risk and the Sub-basin Erosion Expectation were determined. Two soil loss scenarios were simulated: 1) adequacy of the cover-management and the support practices to the land use capacity, and 2) farming areas occupied by sugarcane crops without management and contour tillage. The soil loss estimation through RUSLE showed that erosion results from the interaction of natural and anthropogenic factors, but it suffered more influence of the C factor (soil cover and management). The Permissible Land Cover-Management map, associated with... (Complete abstract click electronic access below
Modeling of Land Use Change, Erosion Processes, and Superficial Runoff in the São Domingos Stream Watershed, Santa Cruz do Rio Pardo Municipality, São Paulo State
No full textNo processo de produção do espaço geográfico, o homem promove mudanças no uso da terra e, consequentemente, alterações no ciclo hidrológico, que dão origem a impactos ambientais negativos, tais como o aumento das taxas de erosão do solo, da exportação de sedimentos das bacias hidrográficas e do escoamento superficial, principalmente quando reduz ou elimina a cobertura vegetal. Tais impactos são observados na bacia do Ribeirão São Domingos, localizada no município de Santa Cruz do Rio Pardo – SP, que passou pelos processos de expansão urbana e intensificação da ocupação agrícola a partir da década de 1970. Nesse contexto, o objetivo desta tese foi analisar a influência das transformações ocorridas no uso da terra da referida bacia hidrográfica desde a década de 1960 e em cenários futuros de uso na configuração dos processos de erosão, aporte de sedimentos e escoamento superficial, por meio de modelagem, como subsídio ao ordenamento territorial urbano e rural. Para tanto, foi necessário: caracterizar os usos da terra passados e atuais; simular os cenários futuros; levantar, caracterizar e mapear os solos da área de estudo; ajustar a equação Intensidade-Duração-Frequência (IDF) para utilização nos estudos hidrológicos; realizar as modelagens de erosão e hidrológica; analisar os instrumentos de ordenamento territorial e parcelamento do solo do Plano Diretor do município e propor as alterações necessárias à redução do escoamento superficial e do perigo de inundação na bacia. A metodologia baseou-se na elaboração dos mapas de uso da terra dos anos 1962, 1984, 2004, 2018 e de adequação à legislação florestal vigente, no levantamento semidetalhado de solos e na coleta de dados pluviométricos, fluviométricos e sedimentométricos, que constituíram a base para as modelagens. As alocações espaciais dos cenários futuros de uso da terra foram simuladas pelo modelo Dyna-CLUE. A modelagem de erosão e aporte de sedimentos no exutório da bacia hidrográfica foi realizada no modelo WaTEM/SEDEM, e a modelagem hidrológica foi conduzida no programa HEC-HMS, pelo método do Número da Curva do Serviço de Conservação do Solo dos Estados Unidos. A série histórica de mapas de uso da terra possibilitou a compreensão do processo de modernização da agricultura ocorrido a partir da década de 1970, o declínio da lavoura cafeeira e sua substituição pelas pastagens e culturas agrícolas destinadas à agroindústria ou à exportação, além do crescimento urbano. Os cenários futuros 1 a 4 mostraram a alocação espacial do crescimento urbano, industrial e da área cultivada pelas commodities agrícolas em diferentes intensidades, ao passo que os cenários 5 e 6 representaram as especializações produtivas na produção florestal e na criação de gado, respectivamente. A modelagem de erosão apontou a redução em suas taxas e nas de exportação de sedimentos pela bacia de 1962 a 2018, e a redução ainda maior nos cenários 5, 6 e de adequação à Legislação Florestal (LF) comparada ao ano-base 2018, devido à evolução dos sistemas de cultivo e à adoção de práticas de conservação do solo. O aumento dessas taxas nos cenários 1 a 4 está associado ao crescimento das áreas agrícolas e/ou urbanas em detrimento das pastagens. A modelagem hidrológica evidenciou o aumento do escoamento superficial no período de 1962 a 2018 e nos cenários futuros 1 a 4, e sua redução nos cenários 5, 6, LF e drenagem urbana moderna. Por fim, verificou-se que os parâmetros urbanísticos Taxa de Ocupação e Taxa de Permeabilidade, associados às macrozonas rurais estabelecidas no Plano Diretor do município, possibilitam a expansão urbana e o parcelamento do solo para uso por chácaras de recreio no perímetro da bacia hidrográfica e o consequente aumento da intensidade dos episódios de inundação, o que foi comprovado pelas simulações hidrológicas realizadas nessas condições. Diante deste fato, foi elaborada uma proposta alternativa de macrozoneamento e das diretrizes de uso da terra para o município, para controlar o escoamento superficial na área de estudo.In the process of producing the geographical space, humans promote changes in land use and, consequently, changes in the hydrological cycle, which generate negative environmental impacts such as an increase in soil erosion rates, sediment yield and surface runoff at the watershed outlets, especially when the vegetal cover is reduced or eliminated. These impacts are observed in São Domingos stream watershed, located in the municipality of Santa Cruz do Rio Pardo, in São Paulo state, which has undergone urban expansion and intensification of agricultural use since the 1970s. In this context, this thesis aims to analyze the influence of land use changes in this watershed, since the 1960s and in future use scenarios, in the configuration of erosion processes, sediment yield, and surface runoff by means of modeling, as a subsidy to the urban and rural land use planning. Aiming this objective, the following steps were necessary: to characterize the past and current land uses; to simulate future scenarios; to survey, characterize and map the soils of the study site; to adjust the Intensity-Duration-Frequency (IDF) equation to be used in hydrological studies; to perform erosion and hydrologic modeling; to analyze the land use planning and soil parceling instruments of the municipality’s master plan and to propose the necessary changes in order to reduce runoff and flood hazard in the watershed. The methodology was based on the production of land use maps for the years 1962, 1984, 2004, 2018 and land use adequacy to current forest laws, on semi-detailed soil survey, and the collection of rainfall, discharge, and sedimentometric data, which served as the basis for the modeling. The spatial allocations of future land use scenarios were simulated by the Dyna-CLUE model. The modeling of erosion and sediment yield at the basin outlet was performed based on the WaTEM/SEDEM model, and the hydrological modeling was carried out in the HEC-HMS program, using the US Soil Conservation Service Curve Number method. The time series of land use maps made it possible to understand the agriculture modernization process that started in the 1970s, the decline of coffee plantations, their replacement by pastures and farm crops dedicated to agroindustry or exportation, besides urban growth. Future scenarios 1 to 4 showed the spatial allocation of urban and industrial growth, as well as the increase of commodities cultivated fields in different intensities, whereas scenarios 5 and 6 represented productive specializations in forest production and cattle breeding, respectively. The erosion modeling showed a reduction in soil loss and sediment yield at the watershed outlet from 1962 to 2018, and an even greater reduction in the scenarios 5 and 6, and in an adequacy to Forest Laws (FL) if compared to the base year 2018, due to crop systems evolution and the adoption of soil conservation techniques. The increase of these rates in scenarios 1 to 4 is associated with the growth of farmlands and urban areas over pastures. The hydrological modeling demonstrated the runoff increase from 1962 to 2018 and in the future scenarios 1 to 4, and its reduction in 5, 6, FL, and modern urban drainage scenarios. Finally, it has been verified that the urbanistic coefficients of Occupancy Rate and Permeability Rate, associated with the rural zoning established by the municipality’s master plan, have allowed an urbanization increase and land parceling for recreational farms on the watershed perimeter, and they have increased the intensity of flood events, which was confirmed by the hydrological simulations that reproduced those conditions. Given this fact, an alternative municipality zoning and land use guidelines proposal was developed in order to control surface runoff on the study site
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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