The Ecology of UHE Carlos Botelho (Lobo-Broa Reservoir) and its watershed, São Paulo, Brazil - Brazil
The Ecology of UHE Carlos Botelho (Lobo-Broa Reservoir) and its watershed, São Paulo, Brazil
Area management/restriction/regulation zones and reporting units
The watershed is located in the center of São Paulo State, Southeast of Brazil. The coordinates are: Lat. 22º 10' 08,5" S; Long. 47º 57' 11,7" W. The drainage density is 0.75km/km2. The maximum altitude is 800m. Basin declivity is 0.00575m/m. The local climate is characterised by alternating dry and wet periods, the wetter period falling in summer and autumn, and the winter and spring seasons being mainly dry. Annual precipitation is around 1500 mm per year. Temperatures are typically between 15 °C and 17 °C during the coldest winter month (July); in the warmest summer month (January), water temperatures between 21 °C to 23 °C are recorded. Potential evapotranspiration is between 500 mm to 1000 mm per year. According to the Koppen classification, the climate is described as ‘warm with a dry period’. The watershed is dominated by holocenic sandy sediments. In the lowland areas, hydromorphic and organic soils predominate. Soils derived from basalt intrusion occur in some areas of the watershed, as red soil hotspots. The natural vegetation is characteristically a savanna type, the Cerrado, typical of the continental regions of Brazil, consisting of bushes and trees adapted to a long (six months) dry season with periodic fires. Given the hydrogeochemical character of the watershed, the ionic strength and the nutrient content of the water of Lobo-Broa Reservoir are correspondingly low.
General Characteristics, Purpose, History
The UHE Carlos Botelho (more familiarly known either as Represa do Lobo or Broa Reservoir or, for convenience, referred to in the scientific literature as Lobo-Broa Reservoir), Itirapina, São Paulo, Brazil, was selected in 1971 for a programme of ecological research. The principal objectives of this programme were: To obtain scientific information on processes and functioning mechanisms and the coupling of climatological, physical, chemical, biological and hydrological factors on a long-term basis. To study the main interactions in the watershed (including human impacts), such as the inputs of allocthonous material in the rivers, land/water interrelations, and the hydrological cycle. To study hydrodynamic characteristics of the reservoir, such as turbulence effects, circulation, and advection patterns. To introduce ecological modeling approaches that could be used for prognosis, mainly related to eutrophication planning, and management strategies. To develop management in order to prevent or correct possible eutrophication effects and to provide background information on multiple uses. To develop a management plan for the watershed and the reservoir with emphasis on processes. To utilise this model as an approach for capacity building at various levels. To introduce a methodological system in limnological and ecological research that could be of comparative use in other regions of Brazil.
Affiliation and Network Specific Information