Contributions of organic residues to the establishment of Stylosanthes capitata in degraded soil

Abstract

Organic residues can improve the fertility of degraded soils and help restore vegetation. This study was structured to evaluate the contribution of residues in the chemical conditioning of degraded soil and the establishment of Stylosanthes capitata. The experiment was conducted under protected cultivation conditions in a completely randomized experimental design, following a 4 x 4 x 2 factorial scheme with three replications per treatment and two plants per replication (pots with 10 kg of soil). Residues, aquatic macrophytes (MAC), and sewage sludge (SLU) were added to the soil at doses of 0, 10, 20, and 30 t ha-1. Sugarcane bagasse ash (ASH) was incorporated into the soil at doses of 0 and 20 t ha-1 10 days before SLU, MAC, and S. capitata seeds. The soil was analyzed for fertility and the plants for height, shoot and root fresh and dry mass, and root volume 120 days after sowing. ASH, SLU, and MAC residues increased pH and organic matter, phosphorus, and calcium contents, facilitating plant establishment, standing out the dose of 20 t ha-1 for SLU and MAC. Therefore, the use of these residues can be recommended both as chemical soil amendments and facilitators for S. capitata establishment.