19 documents found, page 1 of 2
High spatiotemporal resolution free surface detection using cost-effective vide...
Martins, Ricardo; Isidoro, Jorge; Lima, João L. M. P. deThe identification of the air-water interface in free surface flows traditionally involves intrusive techniques or costly equipment. Non-intrusive alternatives, such as computer vision, are emerging as highly effective substitutes or supplements for more invasive techniques in laboratory measurements, thanks to their straightforward implementation and cost efficiency. This research specifically delves in the co...
Technologies for the study of hydropeaking impacts on fish populations: Applica...
Alexandre, Carlos M.; Quintella, Bernardo R.; Ovidio, Michaël; Boavida, Isabel; Costa, Maria J.; Palstra, Arjan P.; Lima, Rui L. Pedroso deDam construction and streamflow regulation are increasing throughout the world, with impacts in impounded aquatic ecosystems. Hydropower dams, some of them causing a phenomenon called “hydropeaking” during their operation, are known for having a variety of impacts on downstream aquatic biota, particularly fish, and respective habitat. This can result in significant changes, from the community (e.g., fish assemb...
Using Remote Sensing to Quantify the Joint Effects of Climate and Land Use/Land...
Jardim, Alexandre Maniçoba da Rosa Ferraz; Araújo Júnior, George do Nascimento; Silva, Marcos Vinícius da; Santos, Anderson dosCaatinga biome, located in the Brazilian semi-arid region, is the most populous semi-arid region in the world, causing intensification in land degradation and loss of biodiversity over time. The main objective of this paper is to determine and analyze the changes in land cover and use, over time, on the biophysical parameters in the Caatinga biome in the semi-arid region of Brazil using remote sensing. Landsat-...
Coupling Water Resources and Agricultural Practices for Sorghum in a Semiarid E...
Carvalho, Ailton Alves de; Montenegro, Abelardo A. de A.; Lima, João L. M. P. de; Silva, Thieres George Freire da; Pedrosa, Elvira Maria RegisWater scarcity and changing rainfall distribution have caused uncertainties in relation to agricultural production in semiarid areas. In this context, water reuse for irrigation is a promising alternative, although requiring irrigation and agricultural management. Production of forage plants is strategic for semiarid areas due to their high tolerance to stresses and use as animal fodder. The objective of this w...
Using Quinine as a Fluorescent Tracer to Estimate Overland Flow Velocities on B...
Lima, João L. M. P. de; Zehsaz, Soheil; Lima, M. Isabel P. de; Isidoro, Jorge M. G. P.; Jorge, Romeu Gerardo; Martins, Ricardo GerardoThis study presents a tracer technique based on the fluorescent properties of quinine to help on the visualization of shallow flows and allow a quantitative measurement of overland flow velocities. Laboratory experiments were conducted to compare the traditional dye tracer and thermal tracer techniques with this novel fluorescent (quinine) tracer by injecting a quinine solution and the other tracers into shallo...
The role of stony soils in hillslope and catchment runoff formation
Mujtaba, Babar; Hlaváčiková, Hana; Danko, Michal; Lima, João L. M. P. de; Holko, LadislavThe role of stony soils in runoff response of mountain catchments is rarely studied. We have compared simu-lated response of stony soils with measured catchment runoff for events caused by rains of small and high intensities in the mountain catchment of the Jalovecký Creek, Slovakia. The soil water response was simulated for three sites with stoniness 10–65% using the Hydrus-2D single porosity model. Soil hydra...
Uso de coberturas alternativas do solo para o controle das perdas de solo em re...
Lima, Cleene Agostinho de; Montenegro, Abelardo Antônio de Assunção; Lima, João L. M. P. de; Almeida, Thayná Alice Brito; Santos, Júlio Cesar Neves dosA região semiárida do nordeste brasileiro é marcada por elevadas incertezas quanto à ocorrência de chuvas intensas, bem como por anos sequenciados de secas. Esses fenômenos naturais, somados à reduzida utilização de práticas conservacionistas, podem gerar degradação dos solos. Nesse contexto, o presente estudo objetivou avaliar a importância do uso de cobertura morta e espécies de oleaginosas não convencionais ...
Analysing the Potential of OpenStreetMap Data to Improve the Accuracy of SRTM 3...
Monteiro, Elisabete S. V.; Fonte, Cidália C.; Lima, João L. M. P. deTerrain slope and drainage networks are useful components to the basins morphometric characterization as well as to hydrologic modelling. One way to obtain the slope, drainage networks, and basins delineation is by their extraction from Digital Elevation Models (DEMs) and, therefore, their accuracy depends on the accuracy of the used DEM. Regional DEMs with high detail and accuracy are produced in many countrie...
Improving the positional accuracy of drainage networks extracted from Global Di...
Monteiro, Elisabete S. V.; Fonte, Cidália C.; Lima, João L. M. P. deDrainage networks allow the extraction of topographic parameters that are useful for basins characterization and necessary for hydrologic modelling. One way to obtain drainage networks is by their extraction from Digital Elevation Models (DEMs). However, it is common that no freely available DEMs at regional or national level exist. One way to overcome this situation is to use the available free Global Digital ...
Influência da intensidade de precipitação na geração de escoamento em telhados ...
Silveira, Alexandre; Lima, João L. M. P. de; Dinis, Catarina; Abrantes, João Rafael Cardoso BritoOs sistemas de aproveitamento de água de chuva baseiam-se na coleta do escoamento de superfícies pouco permeáveis, como telhados e ruas. Esses sistemas são projetados, muitas vezes, com dados de pluviômetros, e não de pluviógrafos, e podem desconsiderar informações importantes da quantidade precipitada disponível para aproveitamento. Neste trabalho foram realizados experimentos em laboratório com simulação de c...