Evolução do uso do solo (1980-2018) e qualidade da água superficial, sob domínio da atividade canavieira, na bacia do Ribeirão Santa Bárbara, Goiatuba (GO)

Abstract

The area planted with sugarcane has incresead in the last two decades, in the Brazilian states producing sugar and ethanol. The state of Goiás is currently the third state with the largest number of sugarcane processing units due to its topography and soil conditions favorable to sugarcane cultivation. The municipality of Goiatuba located in the south of Goiás has three sugar and alcohol plants, due to the favorable conditions of the physical environment as regards the climate with two defined water seasons, mainly rainy summer and dry winter, physically well developed soils and flat to gently undulating relief. that allows the mechanization of sugarcane areas. Other positive aspects of the municipality for this cultivation refer to logistics, as it is intersected by state highways and BR 153 and environmental laws that allow the expansion of sugarcane in areas of Cerrado, a biome that occurs in Goiatuba. The research had as objectives: To evaluate the evolution of the use of the soils in the years of 1980, 2000 and 2018 near the Bom Sucesso plant and to carry out water analysis to verify possible alterations from the sugar and alcohol activity. The research was carried out based on bibliographic research on the expansion of sugarcane in Brazil, especially in the state of Goiás and its economic, social and environmental impacts. Location maps, drainage area, soil classification map and soil uses were made to recognize the characteristics of the physical environment occupied by the sugarcane activity and to investigate the evolution of uses in the Santa Bárbara stream basin where the plant is located. Water analyzes were also carried out to assess possible contamination by vinasse, the main industrial by-product of ethanol distillation. The results obtained allow us to affirm that there were signoficant changes regardings the use of the soil after the beginning of the sugar and alcohol activity, reduction in the area destined to pastures and increase of the agricultural area. The results of the water analysis allowed to verify alterations in the COD and total nitrogen levels, indicating probable contamination by vinasse in the researched area.