Biocarvões de casca de arroz e de esterco bovino como condicionadores de solo para a produção do feijoeiro

The use of organic waste from agriculture and livestock in the form of biochar can be a viable alternative both in the process of managing the biomass generated in the recycling of nutrients contained in solid waste. Thus, the present work should aim to evaluate the potential of biochars produced from bovine manure and rice husk in the chemical properties of the soil and in for the common bean plant production. For this, two experiments were set up: both in a greenhouse in a completety randomized design, the first in a 4x2+3 factorial scheme, with four doses of biochar (1, 2, 3 and 4% (m/v)= conditioner mass/soil volume), two types biochar = biochar from dairy cattle manure (BEB) and rice husk biochar (BCA) and three additional treatments (control 1, without liming and without fertilization; control 2, addition of calcium carbonate, magnesium carbonate (P.A) and nitrogenous, phosphate and potassium mineral fertilizers and; control 3, addition of calcium and magnesium silicate and nitrogenous and potassium mineral fertilizers). The second, in a 2x2x2+1 factorial scheme, with eight replications, with two types of biochar = biochar from dairy cattle manure (BEB) and rice husk biochar (BCA) at a 4% dose (m/v) = (conditioner mass/soil volume), with and without acidity correctors (addition calcium carbonate and magnesium carbonate (P.A)), without and whit phosphorus and a control treatment (without the addition of biochar, acidity corrective and phosphorus). In the first experiment, on the soil samples from each pot, collected after 20 days of incubation with treatments (first stage), the following analyzes were performed: total carbon, pH in water; phosphorus extracted by Mehlich 1 solution and quantified by colorimetry with ammonium molybdate; phosphorus extracted by Mehlich 1 solution and by ion exchange resin and quantified by spectrometry with inductively coupled plasma (ICP-MS/MS); exchangeable aluminum, calcium and magnesium; cation exchange capacity; base saturation; soluble silicon and dry mass of shoots and roots of common bean plant. In the second experiment, in the soil of each pot, collected after 30 days of incubation with treatments, the total carbon (CT) was determined; total nitrogen; pH in water; phosphorus extracted by Mehlich 1; aluminum (exchangeable acidity); exchangeable calcium, magnesium and potassium; cation exchange capacity and base saturation in addition to the dry mass of shoots (MSPA), and roots (MSRA), dry mass of grains (MSGR) and macro and micronutrient contents of common bean plant. The biochars corrected the acidity of the soil, increased the capacity for cation exchange, carbon and soil nutrients, especially at the higher doses of biochar from cattle manure. The soluble silica present in the biochar contributed to increase the availability of phosphorus in the soil and did not interfere in the method of determining the available phosphorus. The common bean plant production increased in the soil corrected with biochars, but it was lower than that obtained in the conventional treatment, where soil acidity correctives and mineral fertilizers were added.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico

FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior