Phytoplankton community dynamic detection from the chlorophyll-specific absorption coefficient in productive inland waters

Abstract Aim: In this research, we investigated the spectral variability of the specific phytoplankton absorption coefficient, a*φ, measured in a tropical meso-to-hypertrophic reservoir, aiming to find spectral features associated with the chlorophyll-a (chla) and other accessory pigments present in different phytoplankton species. Methods To accomplish this research, two fieldworks were carried out in different seasons in order to report a high bio-optical variation. Phytoplankton absorption coefficient, aφ, and chla concentration were measured in laboratory to estimate a*φ. Results The outcomes have indicated that there is a remarkable phytoplankton community dynamic as spatially as seasonally. Chla absorption features were well-defined at 440 nm and 675 nm. Conclusions All the a*φ spectra exhibited the absorption peak around 630 nm associated with phycocyanin pigment present in cyanobacteria. Some spectra have shown a peak at about 460 nm, which is related to chlorophyll b and chlorophyll c (chlb and chlc, respectively) found in different phytoplankton species. In turn, absorption features of carotenoids around 490 nm also were identified, however, well defined just in curves measured in austral autumn. Such spectral features are found in phytoplankton groups already identified in the study area such as Chlorophyceae, Bacillariophyceae, Cyanophyceae, Conjugatophyceae, Chrysophyceae, among others. We expect that the results are useful in researches about remote sensing of phytoplankton and eutrophication in reservoirs

Checklist das Cryptophyceae do estado de São Paulo, Brasil

Usando como base de informações a monografia sobre o grupo publicada pelo projeto Flora Ficológica do Estado de São Paulo (Programa BIOTA), o acervo depositado no Herbário Científico do Estado de São Paulo Maria Eneyda P. Kauffmann Fidalgo (SP), a Lista de Espécies da Flora do Brasil e artigos científicos, dissertações e teses (com descrições e ilustrações) temos: nove gêneros e 39 espécies de criptoficeas, sendo 16 espécies exclusivas para o Estado de São Paulo, todas registradas em ambientes de água doce. A carência de especialistas no Estado de São Paulo e no Brasil, além de problemas de estratégia amostral, necessidade de uso da microscopia eletrônica e ausência de estudos de biologia molecular, são fatores que devem ter subestimado o conhecimento taxonômico de Cryptophyceae no Estado.Based on the information provided by the monograph on the group published by the project Phycology Flora of São Paulo (BIOTA), the collection deposited in the Scientific Herbarium Mary P. Eneyda Kauffmann Fidalgoof the State of São Paulo, the List of Endangered Species of the Flora of Brazil and scientific papers, dissertations and theses (with descriptions and illustrations), there are nine genera and 39 species of cryptophytes, 16 of which are unique species to the State of São Paulo, all recorded in freshwater environments. The lack of specialists in the State of São Paulo and Brazil as well as problems in the sampling strategy, the necessary use of electronic microscopy and the absence of molecular biology studies are factors that must have underestimated the taxonomic knowledge of Cryptophyceae in the state.Universidade Federal do Rio de Janeiro (UFRJ)Universidade Estadual Paulista Julio de Mesquita Filho Centro de AquiculturaUniversidade Estadual Paulista Julio de Mesquita Filho Centro de Aquicultur