Currently water resources come under great pressure due to increased direct consumption by households and for production activities. At the same time, water is usually returned to natural systems in inadequate quality conditions. Pressure for power generation has also caused significant impact by interrupting the physical continuity of river segments and by altering river flow regimes, which affect migratory fish populations and other animals.
Zoning is the identification and delineation of landscape zones, according to their potential and vulnerabilities, based on environmental factors of the physical, biological and socioeconomic environment in each ecosystem. Therefore, environmental zoning requires identifying relevant parameters to be prospected, based on water use conflicts and the environmental and socioeconomic characteristics of each basin.
An index of suitability for the Guaíba Basin based on various socioeconomic and environmental parameters has been determined; it can be used as basis for the licensing of new barriers and therefore the preservation of migratory fish species in the region.