Lixiviação de nitrato em Latossolo cultivado com milho após aplicações sucessivas de lodo de esgoto

Abstract

Resumo -O objetivo deste trabalho foi avaliar a lixiviação de nitrato causada por aplicação de lodo de esgoto e adubo mineral, em Latossolo cultivado com milho. As doses de N da adubação mineral (AM), em cinco cultivos, foram: 51, 90, 100, 90 e 100 kg ha -1 . Nos tratamentos com lodo (L0N, L1N, L2N, L4N e L8N Nitrate leaching in a Typic Haplustox planted with mayze after successive applications of sewage sludgeAbstract -The objective of this work was to evaluate nitrate leaching caused by applications of sewage sludge and mineral fertilizer in a Typic Haplustox cultivated with mayze. N aplication rates in five crops, in the treatment with mineral fertilizer (AM), were 51, 90, 100, 90 and 100 kg ha -1 . In the sludge treatments (L0N, L1N, L2N, L4N and L8N), the rates of available N applied to each crop were equivalent to zero, one, two, four, and eight times those of AM. N-NO 3 -leaching occurred in all treatments, following the order AM<L0N<L1N<L2N<L4N<L8N. Mean total losses of N-NO 3 -in treatments L1N, L2N, L4N and L8N reached 430, 1,020, 2,400 and 3,970 kg ha -1 , respectively (28, 42, 54 and 45% of the total N applied, respectively). Treatments L2N, L4N and L8N showed the greatest soil solution N-NO 3 -concentrations during the fourth crop, with peak values varying between 86 mg L -1 (treatment L2N) and 464 mg L -1 (treatment L8N). In treatments AM, L0N and L1N,concentrations during the fourth crop varied from 5 to 9, 19 to 36, and 33 to 71 mg L -1 , respectively.

Atributos físicos do solo, adubado com lodo de esgoto e silicato de cálcio e magnésio

“…Às vantagens agronômicas da aplicação desses resí-duos nas lavouras, somam-se dois importantes aspectos da sustentabilidade ambiental, o primeiro representado pela reciclagem de nutrientes e da energia (matéria orgâ-nica) nele contido e, o segundo, pela contribuição dessa reciclagem para a preservação das jazidas que fornecem os minérios utilizados na fabricação dos adubos comerciais (Dynia et al, 2006).…”

Cultivo do milho e disponibilidade de P sob adubação com cama-de-frango

“…A resposta aos resultados encontrados pode estar relacionado ao fato de que variações na concentração de nutrientes disponíveis nos solos estão relacionados com a taxa de mineralização dos resíduos no solo (Dynia et al, 2006).…”

Risk simulation of soil contamination by polycyclic aromatic hydrocarbons from sewage sludge used as fertilizers

“…Treatments consisted of three SS rates: (i) control plots (without SS or mineral fertilizer-STEST); (ii) plots treated with 28.15 t ha -1 of SS, correspondent to one regular nitrogen (N) rate for corn crop provided by mineral fertilization (SDL1N); and (iii) plots treated with 225.2 t ha -1 of SS, correspondent to 8-fold the regular N rate for corn crop provided by mineral fertilization (SDL8N). The SS rates were calculated to supply the crop demand, based on the SS-N concentration supposing a 30% N mineralization rate, 26 and on the soil available N concentration. The SS rates were complemented with potassium (K), according to the plant K demand, added as mineral fertilizer (KCl).…”

“…Soil samples were obtained from a field experimental area of Embrapa Meio Ambiente (Embrapa Environment), where a long-term experiment was carried out with corn plants grown in soils amended with SS for six consecutive years. 11,14,26 …”

“…Soil samples were obtained from a field experimental area of Embrapa Meio Ambiente (Embrapa Environment), where a long-term experiment was carried out with corn plants grown in soils amended with SS for six consecutive years. 11,14,26 Experimental Field experiments were carried out in a clay texture distroferric red oxisol (sand loam rhodic oxisol, typic Nine experimental plots of 10 × 20 m cultivated with corn plants were used. The experiment was arranged in randomized complete blocks with three replications.…”