Variação da macrofauna bentônica do entremarés ao longo do arco praial de uma praia arenosa com influência de água doce
Data
2021-02-25
Autores
Cruz, Leonardo de Souza 
Orientadores
Yokoyama, Leonardo Querobim
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A ecologia é uma ciência que busca entender as relações entre fatores ambientais e as comunidades. O ambiente pode determinar uma série de consequências para a comunidade, como por exemplo a sua distribuição espacial. Ou seja, populações podem ocupar espaços diferentes de acordo com as características do ambiente. No contexto da distribuição espacial, um dos ambientes que podem ser estudados são as praias arenosas, ecossistemas afetados por diversos fatores físicos que podem influenciar a estruturação das comunidades. Informações sobre distribuição ao longo da praia são deficitárias, e esse tipo de dado pode ajudar no manejo desse ambiente, principalmente praias com algum nível de urbanização. Desta forma, o objetivo do presente trabalho foi avaliar as variações na distribuição alongshore da macrofauna bentônica de uma praia com aporte de água doce. A praia da Enseada em Bertioga-SP foi escolhida como área de estudo por ter em seu extremo sul o deságue do rio Itapanhaú. Com o aumento da distância do rio, houve uma diferença na composição da comunidade, além de um aumento na riqueza e abundância da macrofauna bentônica. Os dados indicam um aumento na abundância de crustáceos e gastrópodes na direção oposta ao rio, enquanto que um padrão oposto foi verificado para bivalves. Já para a assembleia de poliquetas não houve grande variação ao longo do arco praial. A salinidade pode ter sido decisiva principalmente em questão de recrutamento, para crustáceos e gastrópodes; já para bivalves, filtradores, o fator mais importante pode ter sido a disponibilidade de matéria orgânica trazida pelo rio. Para poliquetas, características do sedimento, como granulometria e matéria orgânica, podem ter maior influência na assembleia, do que características da água, como a salinidade. Para gastrópode, fatores biológicos como presença de alimento podem ter sido mais decisivos. Esse estudo pode ser relevante para o manejo e conservação de praias arenosas, somando mais informações sobre esse ambiente, podendo culminar em melhores resultados de gerenciamento.
Ecology is a science that seeks to understand the relationship between environmental factors and communities. The environment can determine a series of consequences for the community, such as its spatial distribution. In other words, populations can occupy different spaces according to the characteristics of the environment. In the context of spatial distribution, one of the environments that can be studied are sandy beaches, ecosystems affected by several physical factors that can influence the structuring of communities. Information on distribution along the beach is deficient, and this type of data can help in the management of this environment, especially beaches with some level of urbanization. Thus, the objective of the present work was to evaluate the variations in the longshore distribution of the benthic macrofauna of a beach with fresh water. The Enseada beach in Bertioga-SP was chosen as a study area due to its southern end draining the Itapanhaú River. As the distance from the river increased, there was a difference in the composition of the community, in addition to an increase in the richness and abundance of the benthic macrofauna. The data indicate an increase in the abundance of crustaceans and gastropods in the opposite direction to the river, while an opposite pattern was verified for bivalves. As for the polychaete assembly, there was no great variation along the beach arch. Salinity may have been decisive mainly in terms of recruitment, for crustaceans and gastropods; for bivalves, filters, the most important factor may have been the availability of organic matter brought by the river. For polychaetes, sediment characteristics, such as granulometry and organic matter, may have a greater influence on the assembly, than water characteristics, such as salinity. For gastropods, biological factors such as the presence of food may have been more decisive. This study may be relevant for the management and conservation of sandy beaches, adding more information about this environment, which may culminate in better management results.
Ecology is a science that seeks to understand the relationship between environmental factors and communities. The environment can determine a series of consequences for the community, such as its spatial distribution. In other words, populations can occupy different spaces according to the characteristics of the environment. In the context of spatial distribution, one of the environments that can be studied are sandy beaches, ecosystems affected by several physical factors that can influence the structuring of communities. Information on distribution along the beach is deficient, and this type of data can help in the management of this environment, especially beaches with some level of urbanization. Thus, the objective of the present work was to evaluate the variations in the longshore distribution of the benthic macrofauna of a beach with fresh water. The Enseada beach in Bertioga-SP was chosen as a study area due to its southern end draining the Itapanhaú River. As the distance from the river increased, there was a difference in the composition of the community, in addition to an increase in the richness and abundance of the benthic macrofauna. The data indicate an increase in the abundance of crustaceans and gastropods in the opposite direction to the river, while an opposite pattern was verified for bivalves. As for the polychaete assembly, there was no great variation along the beach arch. Salinity may have been decisive mainly in terms of recruitment, for crustaceans and gastropods; for bivalves, filters, the most important factor may have been the availability of organic matter brought by the river. For polychaetes, sediment characteristics, such as granulometry and organic matter, may have a greater influence on the assembly, than water characteristics, such as salinity. For gastropods, biological factors such as the presence of food may have been more decisive. This study may be relevant for the management and conservation of sandy beaches, adding more information about this environment, which may culminate in better management results.
Descrição
Citação
CRUZ, Leonardo de Souza. Variação da macrofauna bentônica do entremarés ao longo do arco praial de uma praia arenosa com influência de água doce. 2021. 29f. Trabalho de conclusão de curso de graduação (Bacharelado Interdisciplinar em Ciência e Tecnologia do Mar) - Instituto do Mar, Universidade Federal de São Paulo, Santos, 2021.