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New education and decision
support model for active behaviour
in sustainable development based
on innovative web services
and qualitative reasoning
Riacho Fundo basin
Riacho Fundo is a small river located in southwestern part of the Federal District, in Brasília, the Brazilian capital. The water basin covers an area of 225,48 km2 in the cerrado, the second largest Brazilian biome The climate shows two clearly distinct seasons, a rainy season from October to April, and a dry season between May to September. Annual pluviosity is about 1.500 a 1.600 milimeters, providing an average outflow of 4,04 m3/s to Riacho Fundo. The springs are located in an area that is favorable to subterranean water consumption, with an average outflow up to 12.000 liters per hour. The rest of the basin (including the river mouth) is less favorable, with an average outflow up to 4.500 liters per hour and a high incidence of dry (or almost dry) wells.
With approximately 15 km of extension, this small river is influenced by more than ten urban areas. Not surprisingly, the Riacho Fundo basin has been of the most disturbed areas of the region since the beginning of Brasilia’s construction. It was progressively impacted by the transformation of rural into urban areas. These changes created a densely populated urban structure where few rural areas produce fruits and vegetables and protect springs and natural vegetation patches. Recent studies show that irregular occupation of the basin have promoted sediment deposits capable of modifying the river path; exploration of gravel pits and soil exposition leading to erosion, and garbage deposition at opened air.
Moreover, the delay in land use regulation postponed the consolidation of the local infrastructure bringing, as a consequence, degradation of water resources. In fact, water pollution brings extensive problems such as contamination of the vegetables produced at the Federal District. Nearly all arms of the river present a high degree of eutrophyzation due to the discharge of sewage, garbage and erosion is found all over the Riacho Fundo sub-basin.
However, the Riacho Fundo water basin may find its way to sustainability. In its area there are 14 legally protected areas, a decisive factor for the preservation of the green areas that still remain. The local vegetation has Cerrado characteristics, especially in these units. Cambissoils (undeveloped soil, generally associated with the campo limpo, moderated declivity and 90-100 cm in depth) predominate in the highest part of the sub-basin. In the lower part, dark-red/yellow latossoils predominate. In this area the soil is plain, with light inclination, with moderate fertility, and is associated with the forest-like phisiognomies Cerrado and Cerradao. In water body surroundings, this region shows Campo vegetations, associated or not with water, and riparian vegetation. The local population is nowadays highly motivated to reduce environmental damage, to clean the river and to protect the Cerrado biodiversity. Following the Brazilian legislation, a water basin Committee is being organized, and qualitative reasoning models produced in the Naturnet-Redime project will support the Committee members in understanding problems and finding solutions for this region.