A systematic analysis and review of the impacts of afforestation on soil quality indicators as modified by climate zone, forest type and age

This global systematic analysis and review investigate the impacts of previous land use system, climate zone, forest type age on soil organic carbon (SOC), total nitrogen (TN), phosphorus (TP) stock, bulk density (BD) pH at layers 0–20, 20–60 60–100 cm, following afforestation. Data came from 91 publications SOC, TN TP stock changes, covering different countries zones. Overall, afforestation significantly increased SOC by 46%, 52% 20% cm depths, respectively. It also shallower stocks 28% 22% 0–20 respectively, but had no overall TP. Previous system largest influence with greater accumulations barren compared to cropland grassland. Climate zone influenced for moist cool than other Broadleaf forests were better coniferous increasing investigated profile (0–100 cm). Afforestation <20 years accumulated only surface (0–20 cm), whilst >20 100 depth. Changes positively correlated depths down under all groups, demonstrating that an increase could offset progressive N limitation, maintains accumulation as age. decreased in topsoil cm) <20-year-old did not change >20-year-old forest, suggesting it may become a limiting factor sequestration Following afforestation, BD alongside significant increases depth, relationship