Abstract

Soil carbon sequestration represents a critical component of global carbon cycling and climate change mitigation strategies. This comparative study examines soil organic carbon (SOC) storage and sequestration rates between natural forest ecosystems and managed agroecosystems across temperate regions. We analyzed soil samples from 24 sites (12 natural forests and 12 managed agricultural systems) over a 5-year period, measuring SOC content, microbial biomass, aggregate stability, and carbon flux rates. Results demonstrated that natural forests sequestered significantly more carbon (2.8±0.4 Mg C ha⁻¹ yr⁻¹) compared to conventional agroecosystems (1.2±0.3 Mg C ha⁻¹ yr⁻¹). However, agroecosystems implementing conservation practices achieved intermediate sequestration rates (2.1±0.5 Mg C ha⁻¹ yr⁻¹). Soil organic carbon stocks in the top 30 cm were 65% higher in forest soils (89.4±12.6 Mg C ha⁻¹) than in agricultural soils (54.2±8.9 Mg C ha⁻¹). Microbial biomass carbon was 2.3 times greater in forest soils, indicating enhanced biological activity. These findings suggest that while natural forests provide superior carbon sequestration capacity, sustainable agricultural management practices can substantially improve carbon storage in agroecosystems, contributing to climate change mitigation while maintaining food security.