Predictive modeling of trophic status of a tropical reservoir using geographical information systems

This paper describes a method to assess the trophic status (TS) of a tropical reservoir. Barra Bonita reservoir is located in the Tiete River, SP state, Brazil (22°29´S and 48°34´W). Water quality variables were determined at 30 sample points in 18 dates. Data were stored using a geographical information system (GIS) software developed by the Image Processing Division at INPE, Brazil. The spatial distribution of the patches in the reservoir permitted the authors to identify the areas where the inputs of nutrients are critical and to understand how the circulation patterns, depth and other environmental variables are affecting the system.