Effects of Long-Term Management Systems on Soil Quality

摘要

In order to evaluate the impact of different management systems like continuous conventional tillage (CT), continuous conventional tillage and no-tillage (CTNT), both under corn (Zea mays L.) crop, and native forest as a control (NF) some physical and chemical properties of an Alfisol, clay texture, were studied in Botucatu, state of Sao Paulo, Brazil. The results showed that the management systems changed significantly most of the soil chemical and physical properties. The treatments CT and CTNT showed higher values of phosphorus, calcium, magnesium, potassium, base saturation and pH and lower values of aluminium and soil organic matter than NF. Comparing treatments with soil mobilization, CTNT showed better conditions for the chemical properties. The values of chemical properties were higher for the upper layers. The treatment with no mobilization (NF) and that with soil management involving lower soil mobilization (CTNT) showed higher mean weight diameter, floculation degree, available water capacity and total porosity and lower bulk density and microporosity. Soil bulk density was higher and total porosity was lower in the upper layer of CT. Total porosity, microporosity, soil bulk density and floculation degree were higher in the deep layers. The replacement of conventional tillage for no-tillage improves the soil physical quality.