Diversidade taxonômica e morfomêtrica de diatomáceas no sistema estuarino de Santos
Data
2022-02-10
Autores
Silva, Thamires Vieira da [UNIFESP]
Orientadores
Barrera-Alba, José Juan [UNIFESP]
Tipo
Trabalho de conclusão de curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Resumo
As diatomáceas são organismos com uma alta diversidade de espécies,
desempenhando um papel funcional e importante nos sistemas marinhos como
produtor primário marinho, contribuindo no fluxo de carbono e a liberação de oxigênio
pela fotossíntese. Dentre esses sistemas, os ecossistemas costeiros destacam pela
sua importância para a biodiversidade. O presente trabalho teve como objetivo avaliar
a diversidade taxonômica e morfométrica de diatomáceas em ambientes costeiros
marinhos com foco no sistema estuarino de Santos. O estuário engloba cidades
vizinhas e, apesar das ações antrópicas de poluição, o local possui uma grande
diversidade de diatomáceas, possuindo táxons e células de dimensões diferentes,
essas diatomáceas são fundamentais para a compreensão da biodiversidade local e
para dados científicos que contribuem para a diversidade marinha. As amostragens
foram realizadas em quatro coletas realizadas entre janeiro e maio de 2021 no sistema
estuarino de Santos. Foram identificados os táxons de diatomácea usando um
microscópio invertido com sistema de imagens acoplado. Foram obtidas suas
características morfométricas a partir das imagens, complementado com dados
obtidos da bibliografia. Como resultado, foram realizados os cálculos morfométricos
de 4.762 células de diatomáceas, pertencentes a 12 táxons diferentes. Foram
calculados os índices de diversidade taxonômica. Para cada táxon foram calculados
os traços morfométricos máxima dimensão linear (MDL), volume celular (V), superfície
(S) e razão superfície/volume (S/V). O táxon predominante em todas as coletas foi o
gênero Skeletonema, representando entre 60 e 94% do total. A maior riqueza de
espécies (11) foi detectada em janeiro, enquanto os maiores índices de diversidade
(1,3) e equitatividade (0,6) foram registradas no mês de maio, quando Skeletonema
apresentou a menor contribuição (60%). Quanto à morfometria, foi observada uma
distribuição entre táxons com menor S/V e formas como Guinardia e Coscinodiscus,
e táxons com formatos mais alongados e maior S/V como Thalassionema
nitzschioides e Nitzschia. Os menores índices de diversidade morfofuncional foram
registrados também em fevereiro.
Diatoms are organisms with a high diversity of species, playing a functional and important role in marine systems as a primary marine producer, contributing to the flux of carbon and the release of oxygen by photosynthesis. Among these systems, coastal ecosystems stand out for their importance for biodiversity. The present work aimed to evaluate the taxonomic and morphometric diversity of diatoms in coastal marine environments with a focus on the Santos estuarine system. The estuary encompasses neighboring cities and despite the anthropic actions of pollution, the place has a great diversity of diatoms, having taxa and cells of different dimensions, these diatoms are fundamental for the understanding of local biodiversity and for scientific data that contribute to marine diversity. The samples were collected in four collections carried out between January and May 2021 in the Santos estuarine system. Diatom taxa were identified using an inverted microscope with a coupled imaging system. Its morphometric characteristics were obtained from the images, complemented with data obtained from the bibliography. As a result, morphometric calculations were performed on 4,762 diatom cells, belonging to 12 different taxa. Taxonomic diversity indices were calculated. For each taxon, the morphometric traits maximum linear dimension (CDM), cell volume (V), surface (S) and surface/volume ratio (S/V) were calculated. The predominant taxon in all collections was the genus Skeletonema, representing between 60 and 94% of the total. The highest species richness (11) was detected in January, while the highest levels of diversity (1.3) and equitability (0.6) were recorded in May, when Skeletonema presented the lowest contribution (60%). Regarding morphometry, they were differentiated between taxa with lower S/V and forms such as Guinardia and Coscinodiscus, and taxa with more elongated shapes and higher S/V such as Thalassionema nitzschioides and Nitzschia. The lowest indices of morphofunctional diversity were also recorded in February
Diatoms are organisms with a high diversity of species, playing a functional and important role in marine systems as a primary marine producer, contributing to the flux of carbon and the release of oxygen by photosynthesis. Among these systems, coastal ecosystems stand out for their importance for biodiversity. The present work aimed to evaluate the taxonomic and morphometric diversity of diatoms in coastal marine environments with a focus on the Santos estuarine system. The estuary encompasses neighboring cities and despite the anthropic actions of pollution, the place has a great diversity of diatoms, having taxa and cells of different dimensions, these diatoms are fundamental for the understanding of local biodiversity and for scientific data that contribute to marine diversity. The samples were collected in four collections carried out between January and May 2021 in the Santos estuarine system. Diatom taxa were identified using an inverted microscope with a coupled imaging system. Its morphometric characteristics were obtained from the images, complemented with data obtained from the bibliography. As a result, morphometric calculations were performed on 4,762 diatom cells, belonging to 12 different taxa. Taxonomic diversity indices were calculated. For each taxon, the morphometric traits maximum linear dimension (CDM), cell volume (V), surface (S) and surface/volume ratio (S/V) were calculated. The predominant taxon in all collections was the genus Skeletonema, representing between 60 and 94% of the total. The highest species richness (11) was detected in January, while the highest levels of diversity (1.3) and equitability (0.6) were recorded in May, when Skeletonema presented the lowest contribution (60%). Regarding morphometry, they were differentiated between taxa with lower S/V and forms such as Guinardia and Coscinodiscus, and taxa with more elongated shapes and higher S/V such as Thalassionema nitzschioides and Nitzschia. The lowest indices of morphofunctional diversity were also recorded in February
Descrição
Citação
SILVA, Thamires Vieira da. Diversidade taxonômica e morfomêtrica de diatomáceas no sistema estuarino de Santos. 2022. 51 f. Trabalho de conclusão de curso (Graduação em Bacharelado Interdisciplinar em Ciência e Tecnologia do Mar) - Instituto do Mar, Universidade Federal de São Paulo, Santos, 2022.