Potential and constraints of organic soil amendments for long-term carbon storage and soil improvement

Abstract

This dissertation includes four studies on organic soil amendments, with a focus on biochar. Meta-analyses showed that biochar increases soil organic carbon (SOC) more stably over time than manure. Long-term field trials confirmed biochar’s persistence in loamy soils, while losses in sandy soils were likely due to leaching. A study on biochar aging revealed changes in its properties, with co-composted biochar enhancing nitrogen retention. Overall, biochar shows high potential for long-term SOC sequestration and soil improvement, particularly when applied under appropriate site and management conditions.