Correction: Biochar affects compressive strength of Portland cement composites: a meta-analysis.

This document is a correction notice for an article titled "Biochar affects compressive strength of Portland cement composites: a meta-analysis." The correction states that the positions of certain figures in the original article were incorrectly reversed. The corrected figures show the effect sizes of biochar addition on the compressive strength of Portland cement composites at different time intervals, as influenced by various factors. The original article has been updated to reflect these corrections. [Extracted from the article]