Análise de componentes principais dos atributos físicos de um latossolo vermelho distrófico típico sob pastagem e mata

Abstract

This work aimed to characterize a typical distrofic red latosol under two grazing systems compared to a soil under native vegetation. Two grazing areas were evaluated, the first under continuous and the second under rotational grazing, at clumps and among clumps. Thirty-six samples were collected at first area grown with Cynodon dactilum cv. Tifton 85. Seventy-two samples were collected at second area with Panicum maximum cv. Tanzânia, 36 in the clumps and 36 between clumps. Other 36 samples were collected in the area under native forest (Cerrado). A regular pattern 5 x 20 m was used to collect samples at the 0-2, 2-7 and 30-35 cm depth. Water availability to plants, soil porosity, dispersion and aggregation were evaluated. The principal component analysis was used. The introduction of grass pastures in the studied area caused changes in the soil physical attributes, mainly at superficial layer. This statistical analysis enabled the combined visualization of soil attributes where those related to porosity changed more in the use and management systems. In the second area, a tendency of better structural quality at 0-2 cm depth compared to other areas under grass pasture was verified.