Does biochar application improve soil aggregation? A meta-analysis

Biochar as a potential soil amendment has been widely used in agricultural soils for improving soil physical properties. However, the effects of biochar addition on soil aggregation are inconsistent in many individual studies. Therefore, we conducted a meta-analysis of 641 comparisons from 119 published studies to assess the combined effects of biochar application on soil aggregation through biochar attributes, initial soil properties, and experimental conditions. Overall, our results indicate that biochar application significantly improved soil aggregation by 16.4 ± 2.5 %, regardless of biochar/experimental/soil conditions. The response ratio (lnR) of biochar-induced soil aggregation had significant variability across different studies. In the context of biochar attributes, there was a higher favorable influence of wood biochar with higher pyrolysis temperature (> 600…