Water erosion under simulated rainfall with instantaneous variation of precipitation intensity and automatic runoff assessment

Autor: Macedo, Pietro Menezes Sanchez
Přispěvatelé: Carvalho, Daniel Fonseca de, Shultz, Nivaldo, Pinto, Marinaldo Ferreira, Pereira, Marcos Gervasio, Salvador, Conan Ayade, Panachuki, El?i, Oliveira, Paulo Tarso Sanches de
Jazyk: portugalština
Rok vydání: 2022
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações da UFRRJ
Universidade Federal Rural do Rio de Janeiro (UFRRJ)
instacron:UFRRJ
Popis: Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2022-10-07T17:05:46Z No. of bitstreams: 1 2022 - Pietro Menezes Sanchez Macedo.pdf: 2335356 bytes, checksum: 0b8b5d7437283d3e0f3e68246fef5e0f (MD5) Made available in DSpace on 2022-10-07T17:05:46Z (GMT). No. of bitstreams: 1 2022 - Pietro Menezes Sanchez Macedo.pdf: 2335356 bytes, checksum: 0b8b5d7437283d3e0f3e68246fef5e0f (MD5) Previous issue date: 2022-02-23 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior CNPq - Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico Water erosion is a natural phenomenon of great importance in the global scenario with regard to the conservation and sustainable exploration of soil and water, and the use of rainfall simulators has generated a lot of relevant information for the understanding of this topic. The improvement of these equipments aiming at the application of rains with variation of precipitation intensity and the development of an electronic runoff collector are crucial steps in the study of erosive processes. Assuming that changing the rotation of the rainfall simulator would make it possible to control the precipitation intensities applied during the simulations and that an automatic runoff collector would facilitate the collection of data in the field, we developed the thesis in three chapters in order to approach the entire procedure adopted in the development and evaluation of devices associated with the InfiAsper rainfall simulator. The aim of the first chapter was to evaluate whether the variation in the shutter disc rotation, associated with its aperture, makes it possible to obtain different rainfall patterns in the InfiAsper rainfall simulator. The installation of electronic components in the simulator's control panel allowed the variation of the shutter rotation during its operation according to previous programming, allowing the simulation of rains with different precipitation patterns. Events with peak precipitation intensity (PI) of 110 mm h-1 and duration of 40 min were adequately simulated by the equipment, with application uniformity above 75%. With this device it became possible to simulate other rain patterns, with different PI and duration, changing the settings for the desired test. The second chapter aimed to evaluate the operability of the InfiAsper rainfall simulator with the new control panel that varies the intensity of precipitation during the application of rain and the soil and water losses associated with different rainfall patterns in a Dystrophic Acrisol with texture clay loam. The panel was programmed to simulate rainfall of 40 min duration and a total depth of 30 mm in a terrain with a slope of 0,09 m m-1, graded in the direction of the contour and in an exposed soil condition. Operating with the new control panel, InfiAsper worked satisfactorily, allowing to vary the intensity of the rains, according to the characteristics of the rains expected in natural events. Intermediate and late rainfall patterns produced greater soil and water losses than the advanced pattern. The intermediate inverted and constant rainfall patterns did?t produce significant losses for the application of an average water depth of 30 mm. The third chapter presents the development and field evaluation of a data collector for rainfall simulators, capable of quantifying runoff volume and automatically estimating the rate of soil loss. Using a microcontroller (Arduino Mega? 2560), sensors with capacitive, ultrasonic and pressure principles were tested to compute runoff volume, and a turbidimeter to compute soil loss rates. Sensors were selected for calibration and data uncertainty. The automatic runoff collector equipped with the PSI.420 pressure transducer and the ST100 turbidity sensor proved to be effective in obtaining and storing data on runoff volume and soil loss obtained during a simulated rain test in the field. A eros?o h?drica ? um fen?meno natural de grande import?ncia no cen?rio global no que diz respeito ? conserva??o e explora??o sustent?vel do solo e da ?gua, e o uso de simuladores de chuvas tem gerado in?meras informa??es relevantes para a compreens?o desse tema. O aprimoramento desses equipamentos visando a aplica??o de chuvas com varia??o de intensidade de precipita??o e o desenvolvimento de um coletor eletr?nico de enxurrada s?o etapas cruciais no estudo dos processos erosivos. Partindo do pressuposto que vairar a rota??o do simulador de chuvas possibilitaria o controle das intensidades de precipita??o aplicadas durante as simula??es e que um coletor autom?tico de enxurrada facilitaria a obten??o de dados em campo desenvolvemos a tese em tr?s cap?tulos de maneira a abordar todo o procedimento adotado no desenvolvimento e avalia??o dos dispositivos associados ao simulador de chuvas InfiAsper. O objetivo do primeiro cap?tulo foi avaliar se a varia??o na rota??o do disco obturador, associada ? sua abertura, possibilita a obten??o de diferentes padr?es de chuva no simulador de chuva InfiAsper. A instala??o de componentes eletr?nicos no painel de controle do simulador permitiu a varia??o da rota??o do obturador durante sua opera??o de acordo com programa??o pr?via, possibilitando a simula??o de chuvas com diferentes padr?es de precipita??o. Eventos com picos de intensidade de precipita??o (IP) de 110 mm h-1 e dura??o de 40 min foram adequadamente simuladas pelo equipamento, com uniformidade de aplica??o acima de 75%. Com esse dispositivo tornou-se poss?vel simular outros padr?es de chuva, com IP e dura??o diferentes, alterando as configura??es para o ensaio desejado. O segundo cap?tulo teve como objetivo avaliar a operacionalidade do simulador de chuva InfiAsper com o novo painel de controle que varia a intensidade de precipita??o durante a aplica??o da chuva e as perdas de solo e ?gua associadas a diferentes padr?es de chuva em um Argissolo Distr?fico com textura franco-argilosa. O painel foi programado para simular chuvas de 40 min de dura??o e l?mina total de 30 mm em um terreno com declividade de 0,09 m m-1, gradeado no sentido da curva de n?vel e em condi??o de solo exposto. Operando com o novo painel de controle, o InfiAsper funcionou satisfatoriamente permitindo variar a intensidade das chuvas, confome as caracter?sticas das chuvas esperadas nos eventos naturais. Padr?es de chuvas intermedi?rio e atrasado produziram maiores perdas de solo e ?gua do que o padr?o avan?ado. Os padr?es de chuva intermedi?rio invertido e constante n?o produziram perdas significativas para a aplica??o de l?mina d'?gua m?dia de 30 mm. No terceiro cap?tulo ? apresentado o desenvolvimento e a avalia??o em campo de um coletor de dados para simuladores de chuva, capaz de quantificar o volume de enxurrada e estimar a taxa de perda de solo automaticamente. Utilizando um microcontrolador (Arduino Mega? 2560), foram testados sensores com princ?pios capacitivo, ultrass?nico e por press?o, para computar o volume de enxurrada, e um turbid?metro, para computar as taxas de perda de solo. Os sensores foram selecionados quanto ? calibra??o e incerteza dos dados. O coletor autom?tico de enxurrada equipado com o transdutor de press?o PSI.420 e o sensor de turbidez ST100 se mostrou eficaz na obten??o e armazenamento de dados de volume de enxurrada e perda de solo obtidos durante ensaio de chuva simulada em campo.
Databáze: OpenAIRE
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