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Neste trabalho, buscou-se avaliar o efeito da adubação com lodo de esgoto submetido a diferentes processos de higienização, sobre os teores de metais pesados e densidade de patógenos no solo e em grãos de milho e feijão caupi consorciados. Os tratamentos no delineamento em blocos casualizados, com três repetições, corresponderam a: Solo sem adubação; Calagem e adubação química; Lodo não higienizado; Lodo higienizado com nim; Lodo higienizado com cal; Composto de lodo e ipomoea; Composto de lodo e ipomoea com fosfato; Lodo não higienizado e fosfato no solo; Lodo higienizado com nim e fosfato no solo; Lodo higienizado com cal e fosfato no solo; Composto de lodo e ipomoea e fosfato no solo. As densidades de patógenos no solo foram extremamente baixas e não diferiram entre tratamentos. As concentrações de metais pesados no solo, mesmo com uso do lodo de esgoto, não extrapolaram os limites máximos de adição anual nem os limites máximos permitidos para solos; apesar disso, as concentrações de Pb em grãos de milho, e de Pb e Cr em grãos de feijão, atingiram valores acima dos limites permitidos para produtos agrícolas, independente da adição de lodo ao solo. Em geral, não houve influência dos tipos de lodo de esgoto em relação aos teores de metais pesados, em grãos de milho e feijão.The objective of this work was to evaluate the effect of fertilization with sewage sludge submitted to different treatments of sanitization on contamination with heavy metals and pathogens in soil and grains of maize - cowpea intercropping system. The experimental design was completely randomized blocks with three replicates, corresponding to: soil without fertilization; liming and chemical fertilization; sewage sludge; sewage sludge sanitized with nim; sewage sludge sanitized with lime; composted sewage sludge and ipomoea; sewage sludge and ipomoea composted with rock phosphate; sewage sludge with rock phosphate incorporated in the soil; sewage sludge sanitized with nim and rock phosphate incorporated in the soil; sewage sludge sanitized with lime and rock phosphate incorporated in the soil; sewage sludge and ipomoea composted with rock phosphate incorporated in the soil. The pathogen density in the soil was extremely low and there were no differences between treatments. The heavy metal concentrations in the soil, including sewage sludge, did not surpass the maximum limits of annual addition and the permissible maximum limits for soils. In spite of this, the concentrations of Pb in maize grains, and Pb and Cr in cowpea grains, reached values above the limits permitted for agricultural products, independent of the addition of sewage sludge in the soil. In general, no influence of type of sewage sludge in relation to content of heavy metals in grains of corn and cowpea was observed.

The sewage sludge is a residue from waste water treatment municipal plants. Because is generated in large amounts, it is a constant preoccupation in relation to environmental contamination. So, sewage sludge agricultural reuse is one technical alternative to environment deposition. The objective of this research was evaluate the effects of sewage sludge increasing rates incorporated in the soil, on phytoavailable Cr, Ni, Pb and Zn soil contents, after sugarcane crop. The experiment was conducted out in a field conditions, at Guariba County, São Paulo state, Brazil. The soil was a Red Argisol, middle texture. The experimental design was a randomized blocks with three replications, in 4x2 factorial scheme plus an additional control treatment. The treatments were resulted from combination between four sewage sludge rates (0, 10, 20 and 40 t ha-1, dry base) and two mineral fertilization levels (50 and 100% of the recommended rate to sugarcane). The control treatment was a soil in it natural conditions. Soil samples were collected in plant lines and between lines and analyzed to heavy metal contents. No differences were observed between the treatments of the factorial scheme and the control treatment. Sewage sludge increasing rates, in general, increased Cr, Ni Pb and Zn soil contents when the samples were from plant-line and between-line. The sewage sludge applied at 40 t ha-1 promoted the largest contents of heavy metals in the soil.

Neste trabalho, buscou-se avaliar o efeito da adubação com lodo de esgoto submetido a diferentes processos de higienização, sobre os teores de metais pesados e densidade de patógenos no solo e em grãos de milho e feijão caupi consorciados. Os tratamentos no delineamento em blocos casualizados, com três repetições, corresponderam a: Solo sem adubação; Calagem e adubação química; Lodo não higienizado; Lodo higienizado com nim; Lodo higienizado com cal; Composto de lodo e ipomoea; Composto de lodo e ipomoea com fosfato; Lodo não higienizado e fosfato no solo; Lodo higienizado com nim e fosfato no solo; Lodo higienizado com cal e fosfato no solo; Composto de lodo e ipomoea e fosfato no solo. As densidades de patógenos no solo foram extremamente baixas e não diferiram entre tratamentos. As concentrações de metais pesados no solo, mesmo com uso do lodo de esgoto, não extrapolaram os limites máximos de adição anual nem os limites máximos permitidos para solos; apesar disso, as concentrações de Pb em grãos de milho, e de Pb e Cr em grãos de feijão, atingiram valores acima dos limites permitidos para produtos agrícolas, independente da adição de lodo ao solo. Em geral, não houve influência dos tipos de lodo de esgoto em relação aos teores de metais pesados, em grãos de milho e feijão. The objective of this work was to evaluate the effect of fertilization with sewage sludge submitted to different treatments of sanitization on contamination with heavy metals and pathogens in soil and grains of maize - cowpea intercropping system. The experimental design was completely randomized blocks with three replicates, corresponding to: soil without fertilization; liming and chemical fertilization; sewage sludge; sewage sludge sanitized with nim; sewage sludge sanitized with lime; composted sewage sludge and ipomoea; sewage sludge and ipomoea composted with rock phosphate; sewage sludge with rock phosphate incorporated in the soil; sewage sludge sanitized with nim and rock phosphate incorporated in the soil; sewage sludge sanitized with lime and rock phosphate incorporated in the soil; sewage sludge and ipomoea composted with rock phosphate incorporated in the soil. The pathogen density in the soil was extremely low and there were no differences between treatments. The heavy metal concentrations in the soil, including sewage sludge, did not surpass the maximum limits of annual addition and the permissible maximum limits for soils. In spite of this, the concentrations of Pb in maize grains, and Pb and Cr in cowpea grains, reached values above the limits permitted for agricultural products, independent of the addition of sewage sludge in the soil. In general, no influence of type of sewage sludge in relation to content of heavy metals in grains of corn and cowpea was observed.

O lodo de esgoto, em razão da sua atuação como condicionador das propriedades físicas, químicas e biológicas do solo, pode se constituir em um importante adubo orgânico. O presente trabalho buscou avaliar o efeito da adubação com diferentes formas de lodo de esgoto sobre a fertilidade do solo e produtividade de grãos de milho e de feijão consorciados. Os tratamentos, no delineamento em blocos casualizados, com 3 repetições, corresponderam a: Solo sem adubação, Calagem e adubação química, Lodo não higienizado, Lodo higienizado com nim, Lodo higienizado com cal, Composto de lodo e ipomoea, Composto de lodo e ipomoea com fosfato, Lodo não higienizado e fosfato no solo, Lodo higienizado com nim e fosfato no solo, Lodo higienizado com cal e fosfato no solo, Composto de lodo e ipomoea e fosfato no solo. Os dados obtidos foram submetidos à análise de variância e teste de Scott-Knott a 5% de probabilidade. A aplicação de lodo de esgoto tratado com cal aumentou a alcalinidade do solo e, também, a disponibilidade de nutrientes para as plantas. Entretanto, as mudanças observadas nas características químicas do solo com a aplicação deste insumo não influenciaram a produtividade das culturas de milho e de feijão consorciados. The sewage sludge, as physical, chemical and biological conditioning of soil properties, has become important organic fertilizer. The aim of this work was to evaluate the effect of the organic fertilization with different sewage sludge on soil fertility and productivity of corn and beans in intercropping systems. The experimental design was a complete randomized blocks with three replicates. The treatments were: soil without fertilization, liming and chemical fertilization, sewage sludge, sewage sludge sanitized with nim, sewage sludge sanitized with lime, sewage sludge and ipomoea composting, sewage sludge and ipomoea composting with rock phosphate, sewage sludge with rock phosphate incorporated at soil, sewage sludge sanitized with nim and rock phosphate incorporated at soil, sewage sludge sanitized with lime and rock phosphate incorporated at soil, sewage sludge and ipomoea composting with rock phosphate incorporated at soil. The data had been submitted to the analysis of variance and test of Scott-Knott at 5% of probability. The application of sewage sludge with lime increased the alkalinity of the soil and, also, the nutrients available for the plants. However, the changes observed in the chemical characteristics of the soil with the application of the biosolid had not influenced the productivity of the cultures of corn and beans in intercropping system.