Summary
This global meta-analysis of paired empirical observations demonstrates that converting annual cropland to perennial crops increases soil organic carbon by approximately 20% in the top 30 cm over a 20-year period (6.0 ± 4.6 Mg/ha gain), with a smaller 10% net gain across the full 100 cm profile. Conversely, conversion of natural pasture to perennial crops resulted in SOC losses, whilst forest-to-perennial conversion showed mixed effects with SOC gains at 0–30 cm but substantial losses at depth. The authors present an empirical model identifying temperature, crop age, and soil properties as key drivers of SOC dynamics, and conclude that evidence supports the FAO's perennialization strategy as a climate mitigation pathway.
UK applicability
The findings are globally derived and likely applicable to UK conditions, particularly for temperate regions. However, the UK's predominant use of improved grassland pastures rather than natural pasture, and its cooler climate relative to many study locations, may moderate the magnitude of SOC gains observed; UK policymakers should consider these results in evaluating perennial crop establishment as part of climate and soil health strategies.
Key measures
Soil organic carbon stocks (Mg/ha) at 0–30 cm and 0–100 cm soil depths; temporal changes in SOC over 20-year periods; empirical model parameters relating SOC change to temperature, crop age, soil bulk density, clay content, and soil depth
Outcomes reported
The study quantified changes in soil organic carbon (SOC) stocks resulting from conversion between annual crops, natural pasture, forests, and perennial crops, and modelled temporal SOC dynamics as a function of time, land use, and site characteristics across a global harmonised dataset of paired observations.
Topic tags
Dig deeper with Pulse AI.
Pulse AI has read the whole catalogue. Ask about this record, its theme, or how the findings apply to UK farming and policy — every answer cites the underlying studies.