Fertilidade de um luvissolo tratado com esterco caprino em diferentes épocas do cultivo.

Abstract

The experiment was designed to assess the fertility of a Luvissolo treated with goat manure and cultivated with grain sorghum [Sorghum bicolor (L.) Moench]. The research was carried out in a screened environment located in an experimental area of the Center for Sustainable Development in the Semi-Arid Region of the Federal University of Campina Grande, in the municipality of Sumé in the state of Paraíba. To carry out the study, materials were collected from the 0-20 cm layer of a Chromic Luvissolo. After being collected and passed through a 0.5 cm sieve, they were placed in plastic pots with a capacity of 5 liters, each pot receiving 3.0 kg of soil. The treatments were distributed in randomized blocks with 10 replications and consisted of three soil cultivation periods: before the application of goat manure, after the application of goat manure and after the initial cultivation of sorghum. When conducting the experiment, the N, P and K levels for the sorghum crop were standardized based on the soil analysis and the water supply was done manually. The humidity of the substrate was kept at 70% of field capacity. For sowing, each pot received two seeds, leaving only the most vigorous after germination. The variables analyzed were related to soil fertility. The lowest average pH was 7.39 in the period after the manure was applied. MO fell by 4.5% until the last growing season.The P content was higher after manure application, at 3.76 mg/kg, while magnesium was higher after sorghum cultivation, at 5.98 cmolc/kg. The results indicate that the application of goat manure significantly affects soil fertility parameters. Initially, there is a reduction in attributes such as pH, MO, Ca and CTC, probably due to the elimination of the manure and the release of organic acids. However, after the sorghum investigation, many of these parameters show recovery or increase, indicating that the continuous intake of manure and the absorption of nutrients by plants improves soil fertility in the long term. This study highlights the importance of proper organic matter management for agricultural sustainability and productivity.