Fractionation of Zn, Cd and Pb in a Tropical Soil After Nine-Year Sewage Sludge Applications * 1

ABSTRACT A long-term field experiment was carried out in the experiment farm of the Sao Paulo State University, Brazil, to evaluate the phytoavailability of Zn, Cd and Pb in a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years, using the sequential extraction and organic matter fractionation methods. During 2005During -2006, maize (Zea mays L.) was used as test plants and the experimental design was in randomized complete blocks with four treatments and five replicates. The treatments consisted of four sewage sludge rates (in a dry basis): 0.0 (control, with mineral fertilization), 45.0, 90.0 and 127.5 t ha −1 , annually for nine years. Before maize sowing, the sewage sludge was manually applied to the soil and incorporated at 10 cm depth. Soil samples (0-20 cm layer) for Zn, Cd and Pb analysis were collected 60 days after sowing. The successive applications of sewage sludge to the soil did not affect heavy metal (Cd and Pb) fractions in the soil, with exception of Zn fractions. The Zn, Cd and Pb distributions in the soil were strongly associated with humin and residual fractions, which are characterized by stable chemical bonds. Zinc, Cd and Pb in the soil showed low phytoavailability after nine-year successive applications of sewage sludge to the soil

Aprovechamiento de la pulpa de umbu (Spondias tuberosa, Arr. Cam.) verde como alternativa para la producción de dulces en masa.

El aprovechamiento del umbu (Spondias tuberosa, Arr. Cam.) verde se presenta como alternativa para reducir las pérdidas pos-cosecha en su estado maduro. El efecto de la adición de pectina y jarabe de glucosa sobre las características físicas, químicas y sensoriales en dulce en masa de umbu verde fueron investigados. Resultados mostraron que la adición de pectina y jarabe de glucosa aumentaron el rendimiento en relación a la pulpa y posibilitaron la produción de un dulce de corte a una menor concentración de sólidos solubles; no hubo diferencia significativa para el pH y promovieron el aumento de la actividad de agua. Los resultados del análisis microbiológico de los dulces se mostraron negativos en cuanto a la presencia de coliformes totales (< 3 NPM/g) en todas las diluciones y el conteo de hongos y levaduras fue menor de 10 ufc (unidades formadoras de colónias)/ml, mostrando que los mismos fueron obtenidos dentro de los patrones de higiene recomendados por la legislación