Raphael A. C. Murano

Poultry manure and mechanical management may influence the distribution of nutrients in the soil profile. The objective was to evaluate physical and chemical changes in a soil with palisade grass ( Brachiaria brizantha cv. Marandu) fertilized with doses of poultry manure with and without use of soil chiseling, after 180 days of application. The design was a randomized blocks with four replicates, in a 5 x 2 factorial arrangement with five doses of manure (0, 1.073, 2.074, 4.148 and 6.222 Mg ha^-1), with and without soil chiseling at 0.20 m. Soil chiseling caused physical changes with an increase of macroporosity in the layer of 0-0.2 m and reduction in soil density and increase in macroporosity and total porosity in the layer of 0.2-0.4 m. With manure doses, pH in the layer of 0-0.1 m showed quadratic fit with maximum value of 7.2. The increases in Ca and Zn in the layer of 0-0.1 m were, respectively, 0.61 cmol_c dm^-3 and 2.99 mg dm^-3. In the interaction of Dose x Management, without soil chiseling, K showed a linear fit and increased 1.39 times; while in the interaction of Dose x Management, with soil chiseling in the layers of 0.1-0.2 and 0.2-0.4 m, P increased by 8.10 and 3.95 mg dm^-3, respectively. In the contrast between the dose zero and manure dose, there was significance for pH, Ca, P and Zn in the layer of 0-0.1 m.

The objective of this study was to evaluate the productive and chemical characteristics of Marandu grass fertilized with poultry manure with or without the use of soil chiseling, during a period of 210 days. The experiment was conducted in a Dark-Red Latosol (Haplustox) of sandy texture, in a randomized block design with 4 replicates, in a 6 x 2 factorial scheme (0, 1.037, 2.074, 4.148, 6.222 t ha^-1 of poultry manure and an additional treatment with chemical fertilizer based on 2.074 t ha^-1, with and without soil chiseling). Grass-cutting management was performed between 95% of light interception by the canopy and the residual height of 0.15 m. The application of poultry manure resulted in an increase of forage production with higher number of cuts (NC). A linear model described the effect of the applied manure doses on dry matter accumulation (DMA), stems + sheaths (SS) and dead material (DM). There was significant interaction between manure doses and soil managements for leaf blade (LB), with greater variations in the treatment without soil chiseling. For plant chemical evaluation, a negative effect of poultry manure was observed on the contents of Ca, Mg, N, S, Mn and Zn, which may be due to the increased number of cuts. Poultry manure positively changed the production of Marandu grass.