Soil erosion in the goiás savannah

Abstract

Agriculture is the main economical activity in the state of Goiás, Brazil. The soils of the savannah (cerrado) became a source of attraction when the mechanization of agriculture, irrigation and the use of corrective chemicals were introduced. Since these technological advances have provided a more intense use, deeper studies on soil characteristics and proper management were required to reduce negative impacts. The degradation of the soil’s physical properties is one of the main processes which cause loss of structural quality and erosion by water. The soil’s texture, specific density, specific gravity of particles, porosity curve and moisture retention of four classes of agricultural soils of Goiás were examined to determine which classes of soil were more susceptible to erosion. Samples were collected from the central to the southwestern region of the state of Goiás, characterized as savannah. Descriptive statistics, with a confidence level of 95%, were employed. Correlation test for averages comparison was used to analyze texture and hydraulic retention curve. Dystrophic quartzose soil had a higher propensity towards erosion than other soil classes. In fact, it was the most vulnerable to erosion by water when the erosion factor (K) was taken into account. Usage techniques and soil management may reduce soil loss by erosion.