Short term spatial and temporal variation of phytoplankton in a shallow tropical oligotrophic reservoir, southeast Brazil

Temporal changes of assemblages may result from environmental variability and reflect seasonal dynamics of their ecosystem. In the subtropics, the hydrological regime is usually characterized by well-defined wet and dry seasons, regulating discharge and influencing a series of environmental variables that affect phytoplankton persistence. Therefore, we may expect that dry seasons are environmentally more stable than wet seasons. We analysed interannual phytoplankton assemblage variability (or, inversely, persistence) in a subtropical reservoir sampled every austral summer and winter during 5 years. We tested (i) if phytoplankton assemblage structure differed between the dry (summer) and wet (winter) seasons; (ii) if assemblage persistence differed between the seasons; (iii) if assemblage persistence was related to environmental stability; and (iv) if assemblage dissimilarity increased over time. Phytoplankton assemblages differed between the summer and winter seasons.Winter indicator species were mostly Bacillariophyceae or Cryptophyceae, whereas Cyanophyceae and Chlorophyceae taxa were more frequent and abundant in summer. Assemblages in the dry season were more persistent among years than those occurring during rainy periods. Similarly, environmental variability tended to be lower among dry than among rainy seasons. The relation between the phytoplankton temporal cycle and the temporal patterns of environmental variability supports our prediction that high environmental stability results in more persistent assemblages. Assemblage dissimilarity increased as sampling years were farther apart, for both seasons. Additionally, assemblages in the rainy periods showed a more pronounced increase in dissimilarity, as their changes among years were less predictable. We found a clear temporal pattern and an increased dissimilarity over time in the phytoplankton assemblage structure. Unravelling these temporal patterns may improve our understanding of phytoplankton temporal dynamics, and may have implications for management and monitoring programs. High dissimilarity of assemblages among years, particularly among rainy periods, can obscure human impacts, and monitoring programs should take this into account.

show abstract

“…2002). Some other indicator species for summer, like Cyclotella spp., are expected to occur preferentially on mixed waters (Lopes et al . 2005).…”

Section: Discussionmentioning

confidence: 99%

Environmental variability drives phytoplankton assemblage persistence in a subtropical reservoir

et al. 2010

View full text Add to dashboard Cite

show abstract

“…For the PEFI area, Lopes et al (2005) reported the occurrence of C. erosa mostly at 3-3.5 m deep and at the bottom of reservoir, because of its lesser demand for light. They also justifi ed the species association with the high levels of TP as an opportunistic feature of all Cryptophyceae.…”

Section: Discussionmentioning

confidence: 99%

“…Cryptophyceae have a wide environment spectrum, as they are typical of nutrients and organic matter rich waters (Rosen 1981), but they can also tolerate occasional nutrient, especially N depletion (Haffner & McNeely 1989). In the periphyton community in oligotrophic conditions, C. phaseolus was associated with the greatest ammonium content (Vercellino 2001), whereas in the phytoplankton community C. erosa was associated with high levels of TP and P-PO 4 during the rainy period, mainly at 3-3.5 m deep and the bottom of reservoir (Lopes et al 2005). In mesotrophic conditions, presence of C. marssonii was associated with the high N-NO 3 concentrations (Fonseca 2005).…”

Section: Discussionmentioning

confidence: 99%

“…For the Parque Estadual das Fontes do Ipiranga (PEFI), Cryptophyceae species are commonly included among the main descriptive ones of the planktonic (Tucci 2002, Lopes et al 2005, Biesemeyer 2005, Fonseca 2005) and periphytic (Vercellino 2001, Barcelos 2003 communities. Experimental studies observed the replacement of Cyanophyceae by Cryptophyceae species under mesotrophic conditions (Crossetti & Bicudo 2005), and the association of Cryptomonas erosa to the high N availability in the system (Ferragut 2004).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cryptophyceae population dynamics in an oligo-mesotrophic reservoir (Ninféias pond) in São Paulo, southeast Brazil

Bicudo

Ferragut

Massagardi

2009

Hoehnea

View full text Add to dashboard Cite

Cryptophyceae population dynamics in an oligo-mesotrophic reservoir (Ninféias Pond) in São Paulo, southeast Brazil). Vertical and temporal dynamics of Cryptophyceae population was studied in an oligo-mesotrophic reservoir, the Ninféias Pond, located in the Parque Estadual das Fontes do Ipiranga, south of the Municipality of São Paulo, state of São Paulo, southeast Brazil. Material studied was collected from January to December 2000. Individual specimens of Cryptophyceae were present in all samples. Thermal stratifi cation and mixing processes do not seem to directly infl uence temporal distribution of Cryptophyceae, but may interfere in their vertical distribution. Four out of the 10 species presently identifi ed (C. brasiliensis, C. curvata, C. erosa and C. marssonii) presented greatest population densities and highest frequency of occurrence. PCA showed that the species' vertical distribution scale was more important towards ordination of samples. Greatest growth of C. erosa was noticed below 1 m depth in all months sampled. Cryptomonas brasiliensis was highly representative at the surface of reservoir, mainly during the warmer months (January-February, October and November). Considering the temporal scale, results did not demonstrate seasonal distribution of Cryptophyceae, but in the vertical scale, results evidenced a heterogeneous distribution of the group.RESUMO -(Dinâmica da população de Cryptophyceae em um reservatório oligo-mesotrófi co (Lago das Ninféias) em São Paulo, Brasil sudeste). A dinâmica vertical e temporal das populações de Cryptophyceae foi estudada em um ambiente oligo-mesotrófi co -Lago das Ninféias -situado no Parque Estadual das Fontes do Ipiranga, sul do Município de São Paulo, estado de São Paulo, região sudeste do Brasil. O material estudado foi coletado de janeiro a dezembro de 2000. A presença de representantes da classe Cryptophyceae foi detectada em todas as amostras coletadas. Estratifi cação térmica e mistura parecem não ter infl uência direta sobre a distribuição temporal das Cryptophyceae, mas podem atuar sobre a repartição vertical de suas espécies. Das 10 espécies identifi cadas, quatro (C. brasiliensis, C. curvata, C. erosa and C. marssonii) apresentaram as maiores densidades populacionais e as mais altas freqüências de ocorrência. A ACP mostrou que a escala vertical de distribuição das espécies pesou mais na ordenação das unidades amostrais. A maior densidade de C. erosa foi detectada abaixo de 1 m de profundidade em todos os meses amostrados. Cryptomonas brasiliensis foi altamente representativa na superfície do reservatório, principalmente, durante os meses mais quentes do ano (janeiro, fevereiro, outubro e novembro). Na escala temporal, os resultados não demonstraram distribuição sazonal das Cryptophyceae, porém, na escala vertical, tais resultados mostraram uma distribuição heterogênea das espécies. Palavras-chave: Brasil, Cryptophyceae, dinâmica de populações, reservatório urbano oligo-mesotrófi co

show abstract

“…Segue aos dois trabalhos acima o de Lopes (1999) sobre a variação nictemeral durante cinco dias consecutivos do período de chuvas e outros cinco do período de seca, que identificou Peridinium gatunense e P. umbonatum para o Lago do IAG. Lopes et al (2005) e Lopes et al (2009) foram as publicações derivadas dessa Tese de Doutorado e ambas referiram a presença de P. gatunense no Lago do IAG, mas não a de P. umbonatum, porque a densidade relativa desta última jamais foi suficiente para consta-la entre as espécies descritoras do sistema. As mesmas duas espécies já referidas foram novamente identificadas por Rosa (2001), em um trabalho que avaliou a possibilidade de utilização dessas espécies como indicadoras de condição ambiental oligotrófica.…”

Section: Introductionunclassified

Criptógamos do Parque Estadual das Fontes do Ipiranga, São Paulo, SP. Algas, 35: Dinophyceae (família Peridiniaceae)

Bicudo

2013

Hoehnea

View full text Add to dashboard Cite

Cryptogams of Parque Estadual das Fontes do Ipiranga, São Paulo, SP). Algae, 35: Dinophyceae (Family Peridiniaceae). Floristic survey of family Peridiniaceae (Dinophyceae) in Fontes do Ipiranga State Park, city of São Paulo, São Paulo State, southeast Brazil. Two genera (Peridinium and Peridiniopsis ) and five species were identified. Peridinium is the genus with the largest number of species (four) in the area. Peridinium gatunense and P. umbonatum var. umbonatum are the best represented taxa geographically occurring in three localities, followed by P. willei in two localities; and P. cinctum and Peridiniopsis cunningtonii were the least represented, occurring in a single locality each.

show abstract

Short term spatial and temporal variation of phytoplankton in a shallow tropical oligotrophic reservoir, southeast Brazil

Cited by 33 publications

References 16 publications

Environmental variability drives phytoplankton assemblage persistence in a subtropical reservoir

Environmental variability drives phytoplankton assemblage persistence in a subtropical reservoir

Cryptophyceae population dynamics in an oligo-mesotrophic reservoir (Ninféias pond) in São Paulo, southeast Brazil

Criptógamos do Parque Estadual das Fontes do Ipiranga, São Paulo, SP. Algas, 35: Dinophyceae (família Peridiniaceae)

Contact Info

Product

Resources

About