Biossólido na nutrição de Urochloa brizantha cv. Marandu

Abstract

The issue of final disposal of biosolids generated in urban wastewater treatment processes is emerging in Brazil, to the extent that deploy and operate effectively, the collection and sewage treatment systems in the country, and this tends to increase. In this context, the practice of recycling in agriculture, alternative enshrined in developed countries, stands out as the most appropriate option for both reduce pressure on the exploitation of natural resources, as to avoid most striking options on the population and the environment. For agricultural use of sewage sludge is required its stabilization process, involving physical, chemical and biological processes, aiming at reducing or eliminating some of the negative characteristics of the sludge, especially the smell and the attraction of insects; addition to reducing the concentration of pathogens. Thus, this study was aimed at evaluating the use of sewage sludge obtained by disinfection of sewage sludge by hydrated lime combination and solarization in providing nutrients for the initial establishment of Urochloa brizantha cv. Marandu. The experiment was conducted in a greenhouse at the Universidade Federal de Uberlândia, Campus Umuarama, with sowing brachiaria in pots of 5 kg of soil (Oxisols), with the adoption of a randomized block design, with 4 blocks and 10 treatments with two plants per plot, and the conduct of 4 plants per pot. The treatments were as follows: mineral fertilizer 03-30-10 (120 kg ha-1 P2O5); biosolids (60 kg ha-1 N); biosolids (48 kg ha-1 N) + mineral fertilizer 03-30-10 (120 kg ha-1 P2O5); biosolids (60 kg ha-1 N) + plaster agricultural (40 kg ha-1 S); biosolids (60 kg ha-1 N) + magnesite (30 kg ha-1 Mg); biosolids (60 kg ha-1 N) + simple superphosphate (120 kg ha-1 P2O5); biosolids (60 kg ha-1 N) + verdigris (60 kg ha-1 K2O); biosolids (60 kg ha-1 N) + plaster agricultural (40 kg ha-1 S) + magnesite (30 kg ha-1 Mg) + simple superphosphste (120 kg ha-1 P2O5) + verdigris (60 kg ha-1 K2O); organomineral fertilizer 05-24-08 (120 kg ha-1 P2O5); control treatment (without addition of nutrient sources). It was observed that the biosolid application more mineral fertilizer provided better results for phytotechnical variables: tiller number, height, chlorophyll a and b, fresh and dry weight, leaf area, leaf content of Urochloa brizantla cv.Marandu. The limed biosolids can be arranged in the pasture without adding heavy metals and pathogens.