Organic amendments influence soil properties, soil microbial diversity, and winter barley traits in a five-year field trial with contaminated soils at a former wood preservation site

Background: Soil contamination with metal(loid)s and organic pollutants creates environmental and health concerns, driving the need for sustainable remediation strategies. Organic amendments can mitigate contamination effects, enhancing soil quality, and potentially increasing biomass production; however, their long-term influence remains an open question. In a five-year field experiment at a former wood-preservation site, this study evaluates the effects of five organic amendments—fresh pig manure (PM), biodigested pig manure (PD), compost (C), compost pellets (Pt), and green waste compost (G)—on Cu-contaminated soils. Here, we evaluated their impacts on physico-chemical soil properties, metal bioavailability, microbial community structure, plant growth and soil fertility. Results: All amendments led to an overall soil improvement, including enhanced physico-chemical properties, increased enzyme activities. The amendments promoted the concentration of soil 16S bacterial genes and impr...