Caracterização morfométrica e funcional de diatomáceas e dinoflagelados de ambientes costeiros do Estado de São Paulo
Data
2024-09-06
Autores
Espanga, Isabella Moreira 
Orientadores
Barrera-Alba, José Juan
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O fitoplâncton é composto por microrganismos unicelulares e coloniais fotossintetizantes que constituem a base da téia trófica. A variação na comunidade fitoplanctônica apresenta consequências ambientais que requerem atenção principalmente em ambientes costeiros como o litoral do Estado de São Paulo, por ser uma região de alta atividade antrópica, propenso a ter níveis variados de contaminantes, poluentes e nutrientes, consequentemente gerando perturbação nos níveis de fitoplâncton. O estudo das variações do fitoplâncton no ambiente têm sido tradicionalmente baseado na diversidade taxonômica. Entretanto, nas últimas décadas têm sido desenvolvidas abordagens de agrupamento por traços funcionais e morfométricos, a fim de entender estratégias adaptativas da comunidade em relação às condições ambientais. Assim, o presente trabalho teve como objetivo analisar e aplicar tal abordagem em diatomáceas e dinoflagelados da região costeira do litoral paulista. Dentre as amostras analisadas, foram obtidos dados morfométricos, a partir da abordagem de formas geométricas associadas , indivíduos distribuídos em 9 táxons de diatomáceas e 3 táxons de dinoflagelados, permitindo determinar a correspondente S/V (razão superfície e volume) e MDL (máxima dimensão linear). Quando representado o S/V frente a MDL*S/V, os táxons foram divididos em 4 grupos, enquanto 3 táxons ficaram isolados. Os grupos 1 (Odontella spp e Melosira spp) e 3 e (Pleurosigma spp, Prorocentrum spp e Podolampas spp), respectivamente, em conjunto dos táxons Amphisolenia spp e Coscinodiscus spp apresentaram os menores valores para S/V (<0,5µm-1 ), enquanto os táxons Asterionellopsis glacialis e Amphisolenia spp apresentaram os valores mais altos de MDL*S/V (>100). Entretanto, ao aplicar as estratégias ecológicas C-S-R, foi possível observar a maioria dos táxons sendo enquadrados como S-estrategistas e R-estrategistas, enquanto apenas 2 táxons se classificaram como C-estrategistas. Baseado na análise funcional, os táxons analisados foram divididos em 7 grupos funcionais, sendo 4 destes enquadrados como R-estrategistas, aptos para viver em ambientes túrbidos, e os outros 3 grupos se caracterizam como S-estrategistas, apresentando alta eficácia nutricional. Assim, foi possível classificar os organismos tanto do ponto de vista morfométrico quanto funcional, oferecendo resultados quanto às suas estratégias adaptativas e respostas à variações ambientais, podendo suplementar estudos tradicionais da comunidade fitoplanctônica da região.
The phytoplankton community is composed of unicellular and colonial photosynthetic microorganisms responsible for being the base of the food web. The variation in the community offers consequences for the environment that requires attention especially on coastal areas like the coast of São Paulo State, marked by its high anthropogenic activity making it susceptible to varying levels of contaminants and pollutants, which can cause disturbances for phytoplankton. The study of phytoplankton variations has traditionally been based on taxonomic diversity. However, recently different approaches grouping the organisms by functional and morphometric traits have been developed to help understand the adaptive strategies of the community related to the environmental conditions. For this reason, the present work aims to analyze and apply those approaches to diatoms and dinoflagellates from the coastal regions of São Paulo. Between the samples analyzed, the morphometric data were obtained using geometric shapes associated with the individuals among 9 diatom taxa and 3 dinoflagellate taxa, allowing to determine the corresponding S/V (surface/volume ratio) and MDL (maximum linear dimension). When analyzing S/V against MDL*S/V the taxa were divided into 4 groups, while 3 taxa remained isolated. Thus, groups 1 (Odontella spp and Melosira spp) and 3 Pleurosigma spp, Prorocentrum spp and Podolampas spp), respectively, followed by Amphisolenia spp and Coscinodiscus spp, presented the lowest S/V values (<0,5µm-1 ), while Asterionellopsis glacialis and Amphisolenia spp showed the highest values for MDL*S/V (>100). However, when applying the C-S-R ecological strategies, most of the taxa were classified as S-strategists and R-strategists while only 2 taxa were classified as C-strategists. Based on the functional approach, the analyzed taxa were divided into 7 functional groups, as 4 of them match the R-strategists characteristics, capable of surviving in turbid environments, and the other 3 groups classified as S-strategists showing high nutritional efficiency. Therefore, it was possible to classify the individuals analyzed from a morphometric and functional perspective, showing results about their adaptive strategies and responses to environmental variations, being able to supplement traditional studies of the phytoplankton community.
The phytoplankton community is composed of unicellular and colonial photosynthetic microorganisms responsible for being the base of the food web. The variation in the community offers consequences for the environment that requires attention especially on coastal areas like the coast of São Paulo State, marked by its high anthropogenic activity making it susceptible to varying levels of contaminants and pollutants, which can cause disturbances for phytoplankton. The study of phytoplankton variations has traditionally been based on taxonomic diversity. However, recently different approaches grouping the organisms by functional and morphometric traits have been developed to help understand the adaptive strategies of the community related to the environmental conditions. For this reason, the present work aims to analyze and apply those approaches to diatoms and dinoflagellates from the coastal regions of São Paulo. Between the samples analyzed, the morphometric data were obtained using geometric shapes associated with the individuals among 9 diatom taxa and 3 dinoflagellate taxa, allowing to determine the corresponding S/V (surface/volume ratio) and MDL (maximum linear dimension). When analyzing S/V against MDL*S/V the taxa were divided into 4 groups, while 3 taxa remained isolated. Thus, groups 1 (Odontella spp and Melosira spp) and 3 Pleurosigma spp, Prorocentrum spp and Podolampas spp), respectively, followed by Amphisolenia spp and Coscinodiscus spp, presented the lowest S/V values (<0,5µm-1 ), while Asterionellopsis glacialis and Amphisolenia spp showed the highest values for MDL*S/V (>100). However, when applying the C-S-R ecological strategies, most of the taxa were classified as S-strategists and R-strategists while only 2 taxa were classified as C-strategists. Based on the functional approach, the analyzed taxa were divided into 7 functional groups, as 4 of them match the R-strategists characteristics, capable of surviving in turbid environments, and the other 3 groups classified as S-strategists showing high nutritional efficiency. Therefore, it was possible to classify the individuals analyzed from a morphometric and functional perspective, showing results about their adaptive strategies and responses to environmental variations, being able to supplement traditional studies of the phytoplankton community.
Descrição
Citação
ESPANGA, Isabella Moreira. Caracterização morfométrica e funcional de diatomáceas e dinoflagelados de ambientes costeiros do Estado de São Paulo. 2024. 27 f. Trabalho de conclusão de curso (Graduação em Bacharelado Interdisciplinar em Ciência e Tecnologia do Mar) - Universidade Federal de São Paulo, Instituto do Mar, Santos, 2024.