Below ground carbon inputs to soil via root biomass and rhizodeposition of field-grown maize and wheat at harvest are independent of net primary productivity

Summary

This field study examined the relationship between above-ground productivity and below-ground carbon inputs in maize and wheat crops, measuring both root biomass and rhizodeposition as pathways for soil carbon accumulation. The key finding, as suggested by the title, is that root-derived carbon inputs were decoupled from net primary productivity—implying that soil carbon stocks may accumulate independently of aboveground yield under varying cropping conditions. This has implications for understanding how farming systems contribute to long-term soil carbon sequestration and soil health across different productivity regimes.

UK applicability

The findings are relevant to UK cereal production, particularly regarding soil carbon management in maize and winter wheat systems. Results suggest that soil carbon accumulation pathways via roots may not be proportional to grain yield, which could inform UK policy on sustainable intensification and soil health targets independent of yield maximisation.

Key measures

Root biomass carbon, rhizodeposition carbon flux, net primary productivity, soil carbon inputs

Outcomes reported

The study measured below-ground carbon inputs to soil via root biomass and rhizodeposition in field-grown maize and wheat at harvest. Results indicate that the magnitude of root-derived carbon inputs to soil remained independent of net primary productivity (above-ground yield).

Topic tags