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Made available in DSpace on 2018-11-26T15:45:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Ministry of Fisheries and Aquaculture of Brazil Brazilian Agricultural Research Corporation (Embrapa) National Institute for Space Research (INPE) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Stratification and mixing patterns of a water body are influenced by the variability of atmospheric systems, which can also modify their biogeochemical properties. The primary goal of this study was to analyze the effect of atmospheric cold fronts (CFs) on thermal stratification and water quality parameters in 4 embayments of the Furnas Hydroelectric Reservoir (FHR) (southeastern Brazil), a warm monomictic water body. A secondary goal was to evaluate the implications of this effect on the aquaculture of Nile tilapia Oreochromis niloticus (L.) in net cages. A 2 yr dataset of meteorological and water quality parameters was used to compute heat flux balance components and buoyancy frequency. These parameters were used to evaluate the influence of CFs on FHR water column stability and water quality. It was observed that the passing of CFs increased net heat loss and wind velocity, resulting in a partial mixture of surface waters with deeper layers. These changes in the physical structure of the water column altered the diel cycle of water temperature, led to a slight decrease in dissolved oxygen concentrations and pH values during the stratification period, and contributed to the increase in dilution power at the fish cultivation sites. However, following CF passages, no significant changes were observed in water quality parameters that influenced Nile tilapia cultivation in the FHR. Nevertheless, the understanding of meteorological systems and their influence on the physical and biogeochemical properties of an aquatic system is important for optimal management of aquaculture activities. Natl Inst Space Res, Remote Sensing Div, BR-12227010 Sao Jose Dos Campos, SP, Brazil Brazilian Agr Res Corp, Embrapa Environm, BR-13820000 Jaguariuna, SP, Brazil Sao Paulo State Univ, Dept Environm Engn, BR-12247004 Sao Jose Dos Campos, SP, Brazil Reference Ctr Fdn Innovat Technol, Green Econ Ctr, BR-88040970 Florianopolis, SC, Brazil Indiana Univ Purdue Univ Indianapolis, Dept Earth Sci, Indianapolis, IN 46202 USA Univ Quebec Rimouski, Dept Biol Chim & Geog, Rimouski, PQ G5L 3A1, Canada Sao Paulo State Univ, Dept Environm Engn, BR-12247004 Sao Jose Dos Campos, SP, Brazil CNPq: 313071/2015-2