Essencial oil components of Hypericum androsaemum infusions and their nematotoxic effects against Meloidogyne javanica (Treub) Chitwood.

Real Sociedad Española de Química, CITAB -UM, CBMA - UM, FCTUniversidade do Minho - CITAB -UM, CBMA - UMFundação para a Ciência e a Tecnologia (FCT

Cyanobacteria and Cyanotoxin in the Billings Reservoir (Sâo Paulo, SP, Brazil)

The Billings Complex and the Guarapiranga System are important strategic reservoirs for the city of Sâo Paulo and surrounding areas because the water is used, among other things, for the public water supply. They produce 19,000 liters of water per second and supply water to 5.4 million people. Crude water is transferred from the Taquacetuba branch of the Billings Complex to the Guarapiranga Reservoir to regulate the water level of the reservoir. The objective of this study was to evaluate the water quality in the Taquacetuba branch, focusing on cyanobacteria and cyanotoxins. Surface water samples were collected in February (summer) and July (winter) of 2007. Analyses were conducted of physical, chemical, and biological variables of the water, cyanobacteria richness and density, and the presence of cyanotoxins. The water was classified as eutrophic-hypereutrophic. Cyanobacteria blooms were observed in both collection periods. The cyanobacteria bloom was most significant in July, reflecting lower water transparency and higher levels of total solids, suspended organic matter, chlorophyll-a, and cyanobacteria density in the surface water. Low richness and elevated dominance of the cyanobacteria were found in both periods. Cylindrospermopsis raciborskii was dominant in February, with 352 661.0 cel mL−1, and Microcystis panniformis was dominant in July, with 1 866 725.0 cel mL−1. Three variants of microcystin were found in February (MC-RR, MC-LR, MC-YR), as well as saxitoxin. The same variants of microcystin were found in July, but no saxitoxin was detected. Anatoxin-a and cylindropermopsin were not detected in either period. These findings are of great concern because the water in the Taquacetuba branch, which is transferred into the Guarapiranga Reservoir, is not treated nor managed. It is recommended that monitoring be intensified and more effective measures be taken by the responsible agencies to prevent the process of eutrophication and the consequent development of the cyanobacteria and their toxinsEl Complejo Billings y el Sistema Guarapiranga son embalses estratégicos importantes para la ciudad de Sâo Paulo (Brasil) y áreas circundantes porque, entre otras cosas, el agua es utilizada para el abastecimiento público. Este sistema produce 19 mil litros de agua por segundo, que es suministrado a 5.4 millones de personas. El agua bruta es transferida por el afluente Taquacetuba desde el Complejo Billings hacia el Embalse Guarapiranga, para regular el nivel de agua del embalse. El objetivo de este estudio fue evaluar la calidad del agua en el tramo del Taquacetuba, teniendo como foco las cianobacterias y cianotoxinas. El muestreo de agua bruta superficial fue realizado en febrero (verano) y julio (invierno 2007). Fueron analizadas variables físicas, químicas y biológicas, cianobacteria, riqueza, densidad y la presencia de cianotoxinas. El tramo fue clasificado como eutrófico-hipereutrófico. Las cianobacterias fueron observadas en ambos periodos de colecta. El crecimiento más significativo de algas fue observado en julio, reflejando baja transparencia del agua y niveles más altos en el agua superficial de sólidos totales, materia orgánica, clorofila-a y densidad de cianobacterias en el agua superficial. Una baja riqueza y un elevado dominio de cianobacteria fueron encontrados en ambos períodos. Cylindrospermopsis raciborskii fue dominante en febrero, con 352 661.0 cel mL�1, y Microcystis panniformis fue dominante en julio, con 1 866 725.0 cel mL�1. Tres variedades de microcistina fueron encontradas en febrero (MC-RR, MC-LR, MC- YR), as� como saxitoxina. Las mismas variedades de microcistina fueron encontradas en julio, pero ninguna saxitoxina fue observada. Anatoxina-a y cylindropermopsina no fueron observadas en ningún período. Estas conclusiones son preocupantes porque el agua del tramo del Taquacetuba, que es transferida al Embalse Guarapiranga, no es tratada o manejada. Se recomienda intensificar el monitoreo y medidas más eficaces deben ser tomadas por parte de las agencias responsables para prevenir el proceso de eutrofización y el desarrollo consiguiente de cianobacterias y sus toxina

Ceratium furcoides (Levander) Langhans in reservoirs at the Ebro watershed, Spain and Sao Paulo state, Brazil

This study compares the morphological characteristics of the dinoflagellate Ceratium furcoides from three Ebro basin reservoirs (Spain) and from six reservoirs at São Paulo state (Brazil) with the aim to identify the distinct morphotypes of Ceratium furcoides in Spain and Brazil. We studied the physical and chemical variables to determine the trophic state of each reservoir. Unlike Ceratium hirundinella, Ceratium furcoides is not a frequent species within the plankton community at Ebro Basin reservoirs, however, this species has been responsible of one monospecific bloom at El Val reservoir. Nevertheless, both Ceratium species are considered invasive in South America. Ceratium furcoides has displaced C. hirundinella at São Paulo state reservoirs, reaching high densities, to the extent of forming monospecific blooms. Morphometric analysis was performed by optic and electronic microscopy (DIC and SEM respectively). The analysis shows significant differences in: i) total cell length, ii) horns length and iii) presence or absence of a fourth horn. While the microscopic study allows differentiating morphotypes according to the reservoir typology, a deeper study using molecular genetic techniques on the different populations of C. furcoides would allow to know better the relationship between the dinoflagellate dynamics and the reservoirs trophic states

Taxonomic and non-taxonomic responses of benthic macroinvertebrates to metal toxicity in tropical reservoirs: The case of cantareira complex, São Paulo, Brazil

Benthic macroinvertebrates are organisms that are recognized as water quality bio-indicators. A wide variety of indices and metrics have been shown to respond to a variety of anthropogenic impacts, usually under a general condition of environmental impairment. The absence of a clear distinction in the relations between specific pollutants and biotic variables is very common and can lead to biased interpretation of biomonitoring. The aims of this research were to test taxonomic and non-taxonomic responses to specific environmental conditions instead to general conditions. For this purpose, we estimated the theoretical toxicity by comparing toxicity values published by EPA with metal concentrations in water and sediments. Then we tested the responses of biological variables to toxicity and other environmental conditions using the linear mixed effects models approach. We generated 32 models considering 24 different biological metrics and indices that were grouped in five levels. Taxonomic and abundance metrics were best predictor than functional or tolerance-based indexes. The strongest model was that which considered subfamily taxonomic resolution responding to Al_w and Cr_s.Fil: de Souza, Frederico Guilherme. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Cetra, Maurício. Universidade Federal do São Carlos; BrasilFil: Marchese Garello, Mercedes Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: López Dovál, Júlio César. Universidade de Sao Paulo; BrasilFil: Rosa, André H.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Pompêo, Marcelo L. M.. Universidade de Sao Paulo; BrasilFil: Moschini Carlos, Viviane. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

Influência das condições do habitat sobre a estrutura de herbáceas aquáticas na região do Lago Catalão, Manaus, AM

Na Amazônia, as herbáceas aquáticas são encontradas em todas as tipologias de água, mas sua abundância pode ser influenciada pelas condições limnológicas de cada ambiente. Assim, este trabalho teve como objetivo avaliar a influência das condições do habitat sobre a estrutura de herbáceas aquáticas na região do Lago Catalão, Manaus, AM. Foram avaliadas sete transecções em ambientes de água branca (AB), nove em água decantada (AD) e sete em água mista (AM). Em cada transecção foram identificadas as herbáceas aquáticas, estimada a área de cobertura relativa, calculada a frequência de ocorrência e avaliadas as variáveis turbidez, condutividade elétrica, pH e profundidade. A variação na profundidade indicou que os ambientes de AD e AM eram mais profundos do que AB, já águas mais ácidas e com menor condutividade foram registradas na AM. Foram registrados 32 táxons de herbáceas aquáticas sendo as espécies mais frequentes Paspalum repens, Salvinia auriculata, Pistia stratiotes e Lemna valdiviana. Entre as espécies levantadas, 50% foram comuns aos três ambientes. Por outro lado, algumas espécies ocorreram exclusivamente em ambientes de AB, em AD e em AM. Na AB foram mais frequentes as formas flutuantes, que também apresentaram a maior cobertura neste ambiente; na AD e na AM as emersas apresentaram maior frequência e cobertura. A AM apresentou maior riqueza de herbáceas aquáticas em relação aos demais ambientes. As variações registradas indicam que as condições limnológicas dos rios de água branca e preta podem determinar a estrutura da comunidade de herbáceas aquáticas, mesmo em pequenas escalas espaciais