Rossi Gabriella, Beni Claudio
Consiglio per la Ricerca in Agricoltura e L'analisi Dell'economia Agraria, Centro di Ricerca Agricoltura e Ambiente (CREA-AA), via della Navicella 4, 00184 Roma, Italy.
Plants (Basel). 2018 Mar 2;7(1):16. doi: 10.3390/plants7010016.
The organic fraction of sewage sludge administered to agricultural soil can contribute to slowing down the loss of soil's organic carbon and, in some cases, can improve the physical and mechanical properties of the soil. One of the main constraints to the agricultural use of sewage sludge is its heavy metals content. In the long term, agricultural administration of sewage sludge to soil could enhance the concentration of soil heavy metals (as total and bioavailable fractions). The aim of this research was to evaluate the effects of medium-term fertilization with diversely processed sewage sludge on the soil's organic carbon content and humification-mineralization processes, on the physical-mechanical properties of soil and their influence on the pool of potentially bioavailable heavy metals, in order to assess their effectiveness as soil organic amendments. After eight years of sludge administration; an increase in the concentrations of bioavailable form was evidenced in all the heavy metals analyzed; independently of the type of sludge administered. The form of sludge administration (liquid, dehydrated, composted) has differently influenced the soil humification-mineralization processes and the physical-mechanical properties of soil. The prolonged amendment with composted sewage sludge contributed to keeping the soil humification-mineralization process in equilibrium and to improving the physical and mechanical qualities of the treated soil.
施用于农业土壤的污水污泥中的有机成分有助于减缓土壤有机碳的流失，在某些情况下，还能改善土壤的物理和机械性能。污水污泥农业利用的主要限制因素之一是其重金属含量。从长期来看，向土壤中施用污水污泥进行农业处理可能会提高土壤重金属的浓度（包括总量和生物可利用部分）。本研究的目的是评估中期施用不同处理的污水污泥对土壤有机碳含量、腐殖化-矿化过程、土壤物理机械性能及其对潜在生物可利用重金属库的影响，以评估其作为土壤有机改良剂的有效性。在施用污泥八年之后；在所有分析的重金属中，生物可利用形态的浓度均有所增加；与所施用污泥的类型无关。污泥的施用形式（液体、脱水、堆肥）对土壤腐殖化-矿化过程和土壤物理机械性能产生了不同的影响。长期施用堆肥污水污泥有助于保持土壤腐殖化-矿化过程的平衡，并改善处理后土壤的物理和机械性质。
