Jakubus et al., in the journal Sustainability, explored the potential of using sewage sludge-derived compost (SSC) and biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More (SSB) as organic soil amendments for improving soil health. The study focused on analyzing the effects of these amendments on soil carbon compounds, nitrogen, and sulfur levels. The research highlighted the benefits of utilizing sewage sludge in line with carbon farming and nature-based solution strategies.  

The study involved a detailed analysis of quantitative and qualitative changes in soil carbon compounds, such as total carbon (TC), total organic carbon (TOC), humic substances (CHS), labile carbon (LC), and water-extractable organic carbon (WEOC), resulting from the application of SSC and SSB. The research also assessed the variability in total and available forms of nitrogen and sulfur, which are important biogenic components linked to the organic matter of the amendments.  

The experiment was conducted under greenhouse conditions using terra rosa soil amended with SSC or SSB at different application rates (25%, 50%, 75%, and 100% by mass). The results showed that the application of both SSC and SSB led to a significant increase in the levels of the tested parameters compared to the control soil. In general, the application of SSC was more favorable than SSB, as evidenced by higher TOC, total nitrogen, and total sulfur levels. However, the content of available sulfur was significantly higher in the soil fertilized with biochar.  

The study also found that SSC contributed more to humic acid carbon and labile carbon, while SSB had a greater effect on fulvic acid carbon levels. The research results highlighted the validity of processing sewage sludge into compost or biochar for agricultural and reclamation purposes.  

SOURCE: Jakubus, M., Cerne, M., ˇ Palˇci ́c, I., Paskovi ́c, I., Ban, S. G., & Ban, D. (2025). The Application of Sewage Sludge-Derived Compost or Biochar as a Nature-Based Solution (NBS) for Healthier Soil. Sustainability, 17, 1630. https://doi.org/10.3390/su17041630