Revista Caatinga (Jan 2016)
EDAPHIC ATTRIBUTES OF A CROP-LIVESTOCK INTEGRATION SYSTEM IN THE CERRADO BIOME
Abstract
A significant increase in the use of integrated farming systems have been observed in the Brazilian Cerrado, such as crop - livestock integration (CLI), which combined with the no - tillage system (NTS) have shown significant influence on soil properties. Therefore, the objective of this work was to evaluate the influence of a CLI system on the chemical, physical and microbiological soil characteristics, in an area in the Cerrado biome, Montividiu, State of Goias, Brazil. The soil fertility, remaining phosphorus (Prem), total organic carbon (TOC), total nitrogen (Nt), aggregate stability (geometric mean diameter – GMD), microbial respiration (C - CO 2 ) and easily - extractable glomalin - related soil protein (EE - GRSP) were evaluated. Soil samples were collected at depth of 0 - 5 and 5 - 10 cm in three areas with: CLI (13 years of annual rotation with Urochloa ruziziensis ); Urochloa decumbens pasture (15 years of implementation); and native Cerrado vegetation. The CLI area had higher pH, Mg, P available (0 - 10 cm) and Prem (5 - 10 cm) values compared to the other areas, and equal values of TOC, Nt, EE - GRSP (0 - 10 cm) and aggregate stability (5 - 10 cm) compared to the pasture area. The CLI had no differences in C - CO 2 emissions compared to the Cerrado, but had lower rates compared to the pasture. The P available and Prem were sensitive indicators to show the differences between the CLI and pasture systems, with higher contents in the CLI area. The TOC and Nt indicators had no differences between these two systems. The GMD results indicated a better aggregation in the pasture (0 - 5 cm) compared to the CLI area, while the EE - GRSP were similar in these areas. The total values of C - CO 2 emission from the soil aggregates showed the stability of respirometry rates in the CLI and Cerrado areas.