Soil Chemical Properties, Organic Reserves and Root System in Degraded Pasture with Introduction of Leguminoseae.

This work aimed to study the recovery of degraded grasslands through different ways of introducing the Stylosanthes in pasture Urochloa decumbens cv. Basilisk, with assessment of the levels of total N in roots, biomass, area, length and root diameter, and concentration of macro and micronutrients in the soil. The experiment was conducted at the São Paulo Agency for Agribusiness Technology in the city of Andradina - SP, Brazil. The climate according to the Kopen classification is tropical hot and humid with dry winter and the soil of the experimental area was classified as red latosol. The experimental design was a randomized block design in split-split plot (with and without P fertilization), with four replications. The treatments were: Control Urochloa decumbens; partial desiccation with 1.5 ton ha^-1 of glyphosate; complete desiccation with 3.0 ton ha^{- 1} of glyphosate; tillage; soil scarification; harrowing rome (G) and plowing + disking (AG). In G and AG treatments were sown by broadcasting 5 kg of seeds of the leguminoseae Estilosantes cv. Campo Grande (80% Stylosanthes capitata and 20 % S. macrocephala), and the remaining treatments employed direct seeding. Recovery strategies of grass pasture Urochloa resulted in significant differences (P < 0.05) between treatments only for the total N content, there were no differences in geometric characteristics of roots and root biomass. Levels of macro and micronutrients in the soil showed no significant differences between the recovery strategies evaluated (P > 0.05). Fertilization had a significant effect on the content of phosphorus in the soil (P < 0.05). The introduction of Stylosanthes Campo Grande accompanied by techniques such as drying and plowing + disking contributed to increases in N total levels in the root system. The pasture recovery strategies did not result in differences in the chemical attributes for macro- and micronutrients in the soil.