de las Heras Jorge, Mañas Pilar, Labrador Juana
Centro Regional de Estudios del Agua, Universidad de Castilla-La Mancha, Albacete, Spain.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2005;40(2):437-51. doi: 10.1081/ese-200045646.
Sewage sludge production has significantly increased during the last years in European Union (EU) countries, being primarily used for agricultural purposes. In this study, digested sewage sludge was applied to greenhouse soil over a three-year period (2001--2003), with three sludge treatments in the first two years (2, 4, and 6 kg m(-2)) and three more applications using a greater quantity in the last year (6, 8, and 10 kg m(-2)). The effects of sewage sludge application on soil and on a leafy crop (Lactuca sativa L.) were studied. Mineral elements, organic matter, pH, and heavy metals were measured in soil and plant tissues. Pathogen and indicator microorganism dynamics in soil were also determined after each sludge application. Results showed that sewage sludge applications increased organic matter, P, and N Ca content in soil. Furthermore, Zn, Pb, Ni, and Cu content increased in soils, primarily after high doses of sludge. The highest yield value was obtained in the second-year harvest, since the last sludge application did not increase yield. Fecal coliform numbers decreased significantly one month after sludge application. However, total coliforms, Clostridium sulphite-reducers and Salmonella, were present in soils three months after sludge application.
在过去几年中，欧盟国家的污水污泥产量显著增加，主要用于农业目的。在本研究中，消化后的污水污泥在三年期间（2001 - 2003年）施用于温室土壤，前两年有三种污泥处理量（2、4和6 kg m(-2)），最后一年又进行了三次施用量更大的处理（6、8和10 kg m(-2)）。研究了污水污泥施用对土壤和叶菜类作物（生菜）的影响。测定了土壤和植物组织中的矿质元素、有机质、pH值和重金属含量。每次污泥施用后还测定了土壤中病原体和指示微生物的动态变化。结果表明，污水污泥的施用增加了土壤中的有机质、磷、氮和钙含量。此外，土壤中的锌、铅、镍和铜含量增加，主要是在高剂量污泥施用之后。第二年收获时产量最高，因为最后一次污泥施用并未提高产量。污泥施用一个月后，粪大肠菌群数量显著减少。然而，污泥施用三个月后，土壤中仍存在总大肠菌群、亚硫酸盐还原梭菌和沙门氏菌。
