V. Ferreira; S. P. D. Alves; C. C. Sousa; G. R. V. Pinheiro; L. C. R. S. Teixeira; A. L. de Sá Salomão
Abstract
Chlorella vulgaris is one of the most common and characterized algae genus with several applications, including carbon sequestration, biofuel, food production and wastewater treatment. Chlorella sp. are considered suitable to be used as model organisms in space research due to their cultivation flexibility. ...
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Chlorella vulgaris is one of the most common and characterized algae genus with several applications, including carbon sequestration, biofuel, food production and wastewater treatment. Chlorella sp. are considered suitable to be used as model organisms in space research due to their cultivation flexibility. Many studies have been carried out to ensure better conditions for supporting human life on long-term missions in deep space or on planetary surfaces, minimizing the need for resupplies. Regardless of the resilience of the genus Chlorella to space conditions has already been demonstrated, model organisms are useful in the improvement of new technologies. This research aimed to develop the culture conditions and a monitoring system for C. vulgaris, under microgravity, using an image capture device for CubeSats. The image acquisition system consisted of a digital microscope, with remote access, a Single Board Computer, a monitoring computer, and an image processing algorithm. Three microalgae colonies, under laboratory conditions, were evaluated in real time (every 30 minutes) using the size of the colonies as a parameter for evaluating growth rates. The highest microalgae biomass production for the three monitored colonies (C1-C3) was: increase of 28% for C1 after 90 h; 21% for C2 after 84 h; and 36% for C3 after 120 h. The results indicated that the system was able to monitor the growth of microalgae colonies. A specific support is being developed, which allows the installation of this image acquisition system for algae cultivation in a CubeSat, for future studies of algae growth in real microgravity conditions.
I. Y. D. C. Rodrigues; J. D. C. Campos; R. M. Cavalcante; A. C. Coutinho; A. T. Netto; A. L. D. S. Salomão
Abstract
The Jacarepaguá Lagoon (JPAL) is part of a lagoon complex, located in the west zone of Rio de Janeiro city, and has largest drainage area of the complex. JPAL constantly receives the clandestine release of domestic and industrial effluents, in addition to diffuse contributions from drainage waters ...
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The Jacarepaguá Lagoon (JPAL) is part of a lagoon complex, located in the west zone of Rio de Janeiro city, and has largest drainage area of the complex. JPAL constantly receives the clandestine release of domestic and industrial effluents, in addition to diffuse contributions from drainage waters from different sources, with high pollution load. Ecological Risk Assessment (ERA) is an important tool with a more global view of the risks for the management of contaminated areas, including the identification of adverse effects of contaminants on the environment. This study aimed to develop an ERA for the JPAL, using two lines of evidence (LoE): Ecotoxicological and Ecological. The sediments samples were collected in four sampling points. The Ecotoxicological LoE was based on chronic ecotoxicity assays (Chlorella vulgaris and Ceriodaphnia dubia) to estimate the Ecotoxicological Risk. The Ecological LoE was based on the analysis of the richness and abundance of local algae species to estimate the Ecological Risk. The Environmental Risk was estimated by integrating the Risks of the two LoE. The Ecotoxicological Risk was 0.80±0.12, classified as very high risk. The Ecological Risk was 0.746±0.01, classified as high risk. The estimated Environmental Risk was 0.78±0.08, which was a very high risk. In summary, JPAL had an advanced stage of contamination, with a high content of organic matter in the sediment, caused by irregular effluents released. JPAL's current environmental risk exposes the urgent need for more inspection actions to prevent the release of sewage before the total degradation of the local ecosystem.
