城市污泥产品林地施用效果与风险评价

为探究城市污泥产品的林地施用效果,以北京排水集团生产的城市污泥产品(有机营养土、生物碳土、复合生物碳土)为研究对象,在北京市大兴区建立了城市污泥产品林地施用示范区.通过现场施用,研究3种城市污泥产品在不同施肥方式、不同施肥量下对林地环境及毛白杨生长的影响.结果表明,土壤的酸碱度与施肥前相比有小幅度的上升,最终稳定在7....

Application effect and risk assessment of urban sludge products in forest land

To explore the application effect of urban sludge products in forest land. In this study, three kinds municipal sludge products (i.e., organic nutrient soil, biochar soil, and compound biochar soil) produced from Beijing Drainage Group were selected as research objects, and demonstration area for their application in forest was established in Daxing District, Beijing to evaluate the land application effect of those municipal sludge products in forest. The effects of three kinds of municipal sludge products on forest environment and Populus tomentosa growth under different fertilization methods and amounts were investigated via the field experiments. It was found that the pH value of soil increased slightly and finally stabilized at about 7.1 after fertilization. The conductivity of acid-base soil increased with the increase of fertilization ratio, whose highest value was over 1400 μS·cm−1, but there was no salinity risk. After applying municipal sludge products, the contents of all kinds of nutrients in the soil increased significantly and played a dominant role in promoting the growth of plants. The results also showed that the effect of 3 kg·m−2 of application of composite biochar soil was the best. The application of sludge products could promote the growth of plants, improve the fertility of soil and lead to the slightly increase of heavy metals contents in the soil, but all of them met the relevant requirements of the soil quality standard in soil pollution risk control standard for agricultural land and were in a low risk state during the whole monitoring period.