Long term application of pig manure on the chemical and physical properties of Brazilian Cerrado soil

Abstract

Intensive pig farming is an important economic activity and generates a large amount of liquid pig manure as a by-product, which is considered a promising resource for the fertilization of tropical soils, characterized as low natural fertility. In an agricultural area under no tillage soybean-corn cropping system, located in southwest of Brazil, an experiment was carried out with different forms of fertilization; that is, organic fertilization with pig manure (17 years) at different rates of application and with mineral fertilization. Regarding the pig manure application rate, with yearly carbon load of 50 m3 ha−1 tended to promote the mineralization of organic matter, with formation of humic substances and to improve the size of aggregates. The use of LPM promoted little soil carbon addition varying of 0.05-3.41 kg ha−1 with 17 years of LPM application and the continuous application of pig tended to be advantageous for the tropical soil, providing a positive carbon balance, which favored the soil and the environment through the rational waste disposal.

Keywords

• pig slurry
• organic carbon
• soil aggregation