Avaliação da cobertura de macrófitas presentes no Corpo Central I do Reservatório Billings (SP).
Data
2022-12-03
Autores
Santos, Jonathas Ferreira dos [UNIFESP]
Orientadores
Nordi, Cristina Souza Freire [UNIFESP]
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O reservatório Billings é considerado a maior represa da Região Metropolitana de São Paulo (RMSP), a qual tem como principal finalidade o abastecimento público. Contudo, tem problemas relacionados à qualidade da água, provocados pela eutrofização. A eutrofização traz várias consequências para o meio aquático, sendo uma delas o crescimento exacerbado de plantas aquaticas, principalmente das macrófitas e do fitoplâncton. O objetivo desta pesquisa é identificar e mensurar a cobertura de macrófitas existentes no Corpo Central I da represa Billings em uma série temporal (2011 – 2021). Foram realizados levantamentos de campo em sete pontos distribuídos em um trajeto de 6 km para a coleta e identificação de estandes de macrófitas, com registros fotográficos e de coordenadas de cada um dos pontos. A partir do geoprocessamento utilizando o Programa Google Earth Pro foram extraídos padrões de imagens de cada uma das espécies encontradas nos pontos visitados para posterior mapeamento dos estandes das macrófitas na série histórica do Corpo Central I do Reservatório. A técnica de fotointerpretação em tela foi a ferramenta usada para mapear os estandes de macrófitas. O programa QGIS foi utilizado para sobrepor a série de mapas, permitindo a análise da dinâmica de perdas e ganhos na cobertura de macrófitas no Corpo Central I nos últimos 10 anos. Foram identificadas seis espécies diferentes nos pontos de coleta, com distribuição diferenciadas entre os locais de coleta. Foram selecionadas 10 séries históricas de imagens de satélite, nas quais foram vetorizados todos os estandes de macrófitas observados. Os padrões de imagens das espécies identificadas na visita foram utilizados como referência, permitindo quantificar a dinâmica de distribuição das coberturas de macrófitas nos períodos de chuva e seca. A técnica de fotointerpretação em tela mostrou-se eficiente na identificação e vetorização dos estandes de macrófitas existentes no Corpo Central I. Os dados obtidos mostraram a dinâmica de ganhos e perdas na cobertura de macrófitas, contribuindo para a definição de padrões de imagens das espécies de macrófitas identificadas. Considerando que há poucos estudos sobre macrófitas na Reservatório Billings, os dados obtidos neste trabalho poderão contribuir com futuros estudos envolvendo a mensuração das populações das macrófitas na Represa.
The Billings reservoir is considered the largest reservoir in the Metropolitan Region of São Paulo (RMSP), and one of the purposes is public supply, However the reservoir has been suffering problems related to water quality, caused mainly by eutrophication. Eutrophication brings several consequences to the aquatic environment, one of them being the exacerbated growth of macrophytes and phytoplankton. The objective of this research is to identify and measure the existing macrophyte cover in the Central Body I of the Billings reservoir in a time series (2011 - 2021). A field survey was conducted in Billings reservoir at seven points distributed in a 6 km path for the collection and identification of macrophyte stands. The photographic and coordinates records of each point were also obtained Using the Google Earth Pro Program, the species image patterns of each of the points visited were extracted for subsequent mapping of macrophyte stands in the historical series of the Central Body. The photointerpretation technique on canvas was the tool used to map the macrophyte stands. The QGIS program was used to overlay the map series, allowing analysis of the dynamics of losses and gains in macrophyte cover in Central Body I over the past 10 years. Six different macrophytes species were identified at the collection points, with different distributions among the collection sites. Ten satellite images were selected, in which all the macrophyte stands observed were vectored concerning to the image patterns of the identified species during the visit, presenting the dynamics of macrophyte cover distribution in the rainy and dry periods. The work showed the efficiency of the photointerpretation technique in the identification and vectorization of the macrophyte stands existing in the Central Body I using selected images during the analyzed period. This work data allowed obtaining the dynamic in the gains and losses in macrophyte cover. Also contributes to the identification of some macrophyte species and the acquisition of image patterns of these species. The results obtained could contribute to future studies concerning Billings reservoir macrophytes. Bringing a dynamic in the gains and losses in macrophyte cover, contributing with the identification of some collected species. Since there are few studies on macrophytes in the Billings Reservoir, the data obtained in this work may contribute to future studies involving the measurement of macrophytes populations in the dam.
The Billings reservoir is considered the largest reservoir in the Metropolitan Region of São Paulo (RMSP), and one of the purposes is public supply, However the reservoir has been suffering problems related to water quality, caused mainly by eutrophication. Eutrophication brings several consequences to the aquatic environment, one of them being the exacerbated growth of macrophytes and phytoplankton. The objective of this research is to identify and measure the existing macrophyte cover in the Central Body I of the Billings reservoir in a time series (2011 - 2021). A field survey was conducted in Billings reservoir at seven points distributed in a 6 km path for the collection and identification of macrophyte stands. The photographic and coordinates records of each point were also obtained Using the Google Earth Pro Program, the species image patterns of each of the points visited were extracted for subsequent mapping of macrophyte stands in the historical series of the Central Body. The photointerpretation technique on canvas was the tool used to map the macrophyte stands. The QGIS program was used to overlay the map series, allowing analysis of the dynamics of losses and gains in macrophyte cover in Central Body I over the past 10 years. Six different macrophytes species were identified at the collection points, with different distributions among the collection sites. Ten satellite images were selected, in which all the macrophyte stands observed were vectored concerning to the image patterns of the identified species during the visit, presenting the dynamics of macrophyte cover distribution in the rainy and dry periods. The work showed the efficiency of the photointerpretation technique in the identification and vectorization of the macrophyte stands existing in the Central Body I using selected images during the analyzed period. This work data allowed obtaining the dynamic in the gains and losses in macrophyte cover. Also contributes to the identification of some macrophyte species and the acquisition of image patterns of these species. The results obtained could contribute to future studies concerning Billings reservoir macrophytes. Bringing a dynamic in the gains and losses in macrophyte cover, contributing with the identification of some collected species. Since there are few studies on macrophytes in the Billings Reservoir, the data obtained in this work may contribute to future studies involving the measurement of macrophytes populations in the dam.