Sewage sludge application on cultivated soils: effects on runoff and trace metal load

Abstract

The use of sewage sludge in agricultural soils as a macro and micronutrient source and as a soil conditioner has been one of the alternatives for its disposal. However, sewage sludge contains trace metals, which are potential sources of pollution. The goal of this study was to evaluate the effect of sewage sludge application on surface water contamination through runoff when it was applied in a soil cultivated with corn. The effect of sludge application on the concentration and load of copper, nickel and zinc and the volume of runoff water and sediment were evaluated. The experiment was set up in plots used to study erosion losses in Campinas, Sao Paulo State, Brazil. The soil is a clayey Rhodic Hapludox. Three treatments were studied: no sewage sludge, sewage sludge to supply the N required by the crop and twice that amount, with four replications. The water and sediment lost by runoff were measured after each rainfall, and sampled for chemical analysis. The volumes of water and sediment lost by runoff decreased after sewage sludge application. The waste application increased trace metal concentration in the runoff water and sediment, especially zinc, which was present in high concentration in the sewage sludge used. Nevertheless, the load of trace metals transported from the plot was mostly dependent on the total runoff volume. Most of the Cu, Zn and Ni losses were via sediment, and occurred in a few highly erosive rainfall events in the period studied. Key words: Cu, Ni, Zn, erosion, sediment APLICAÇÃO DE LODO DE ESGOTO EM SOLOS AGRÍCOLAS: EFEITOS NA ENXURRADA E NO CARREAMENTO DE METAISRESUMO: O uso de lodo de esgoto em solos agrícolas como fonte de macro e micronutrientes e como condicionador de solos tem sido uma das alternativas para sua disposição final. O lodo de esgoto, entretanto, contém metais que são potencialmente fonte de poluição. Estudou-se o efeito da aplicação de lodo de esgoto na contaminação de águas superficiais por meio da enxurrada proveniente de solo agrícola cultivado com milho. O efeito da aplicação do lodo na concentração e no carreamento de cobre, níquel e zinco e no volume de enxurrada e sedimentos foi avaliado. Os tratamentos foram aplicados em parcelas utilizadas para estudos de perdas por erosão em Campinas, São Paulo, Brasil. O solo era um Latossolo Vermelho férrico argiloso. Os três tratamentos foram: sem lodo, com lodo para suprir o N requerido pela cultura e duas vezes essa quantidade, com quatro repetições. A água e o sedimento perdidos pela enxurrada eram medidos na manhã seguinte de cada chuva e amostrados para análise química. Os volumes de água e de sedimentos perdidos por enxurrada diminuíram com a aplicação do lodo. A aplicação do resíduo aumentou a concentração de metais na água e no sedimento, especialmente do zinco que estava presente em alta concentração do lodo de esgoto utilizado. Entretanto, a carga de metais transportados das parcelas foi dependente principalmente do volume total de enxurrada. A maior parte das perdas de Cu, Ni e Zn foi via sedimento e...

Distribuição espacial de fósforo em Latossolo tratado com lodo de esgoto e adubação mineral

“…O aumento da adsorção de P pode ser, ainda, devido ao aumento da força iônica da solução como resultado das altas concentrações de carbono orgânico dissolvido. Além disto, a MO melhora a agregação das partículas do solo o que aumenta sua estabilidade contribuindo para reduzir o processo erosivo (Maria et al, 2007;Galdos et al, 2009). É provável que essas sejam as razões pelas quais a distribuição de P no solo tratado com lodo de esgoto tenha sido mais heterogênea já que não foram identificadas dependência espacial ou diferenças de concentrações ao longo do declive.…”

Lead sorption and leaching from an Inceptisol sample amended with sugarcane vinasse

“…In soil columns, since they are open systems, the unbalanced conditions are more closely related to natural conditions, where the desorbed species are removed and the reverse reactions are much less probable to occur. Based on the results of the Pb leaching experiment, which is more closely related to the field conditions, special attention must be given to the agricultural areas that receive large quantities of vinasse and are also exposed to contamination with Pb; for example: through the use of phosphate fertilizers (Campos et al, 2005) with sewage sludge or biosolids of urban and industrial origins (Silveira et al, 2003;Borges and Coutinho, 2004;Oliveira et al, 2005;Silva et al, 2006;Torri and Lavado, 2008;Galdos et al, 2009). This can happen where sewage sludge is used as a source of N and vinasse is used as a source of K as may occurs in sugarcane crops (Franco et al, 2008).…”

“…Some of the effects of the vinasse on physical, chemical and biological attributes of soil were studied by Camargo et al (1983), Leal et al (1983), Neves et al (1983), Mattiazzo and Glória (1987), Sengik et al (1988), Franco et al (2008) and Doelsch et al (2009) Pb can be present in soil due to weathering processes, mining and smelting activities (Kabata-Pendias and Pendias, 2000;Sharma and Dubey, 2005), and also by the agricultural use of phosphate fertilizers, sewage sludge or biosolids (Silveira et al, 2003;Borges and Coutinho, 2004;Oliveira et al, 2005;Campos et al, 2005;Silva et al, 2006;Camilotti et al, 2007;Torri and Lavado, 2008;Galdos et al, 2009).…”

Carbon sequestration and greenhouse gases emissions in soil under sewage sludge residual effects

“…The climate is humid-tropical with rainy summers and dry winters, and is considered to be a Cwa type, according to the Köppen classification system (Alvares et al, 2013). The mean annual temperature and rainfall are 20.5 °C and 1,400 mm, respectively, and 76 % of the precipitation occurs between Oct and Mar (Galdos et al, 2009).…”

“…From the perspective of agricultural sustainability, SS use promotes the recycling of nutrients previously removed from the soil by crops (Elser, 2012), while reducing the use of synthetic fertilizers and their detrimental environmental effects (Childers et al, 2011). Also, SS may help prevent soil erosion (Galdos et al, 2009;Garcia-Orenes et al, 2005), increase enzymatic activity in soils (Singh and Agrawal, 2008) and decrease the incidence and viability of phytopathogenic organisms detrimental to crops (Bonanomi et al, 2010).…”