Modern arable and diverse ley farming systems can increase soil organic matter faster than global targets

• Published in: Renewable agriculture and food systems Vol. 39
• Main Authors: Gantlett, Richard, Bishop, Jacob, Jones, Hannah E., Lukac, Martin
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 18.09.2024
• Subjects: Accumulation; Agricultural practices; Agriculture; Arable land; Biodiversity; Biomass; Carbon content; Carbon cycle; Carbon sequestration; Climate change; Climate change mitigation; Crop production; Crop residues; Crop rotation; Experiments; Farming; Farming systems; Farms; Food conversion; Food production; Land use; Legumes; Nutrient cycles; Organic carbon; Organic farming; Organic matter; Organic soils; Pasture; Plant growth; Research Paper; Rotating matter; Soil fertility; Soil improvement; Soil nutrients; Soil organic matter; Soils; Winter; crop residue retention; minimum tillage; diverse species ley; soil organic matter; carbon sequestration; crop rotation
• ISSN: 1742-1705; 1742-1713
• DOI: 10.1017/S1742170524000103

Agriculture can be pivotal in mitigating climate change through soil carbon sequestration. Land conversion to pasture has been identified as the most effective method to achieve this. Yet, it creates a perceived trade-off between increasing soil carbon and maintaining arable food crop production. In this on-farm study, we assessed the potential of incorporating a 2-year diverse ley (consisting of 23 species of legumes, herbs, and grasses) within a 7-year arable crop rotation for soil organic matter accumulation. We established upper and lower boundaries of soil organic matter accumulation by comparing this approach to positive (permanent ley, akin to conversion to permanent pasture) and negative (bare soil) references. Our findings in the 2-year diverse ley treatment show greater soil organic matter accumulation in plots with lower baseline levels, suggesting a potential plateau of carbon sequestration under this management practice. In contrast, the positive reference consistently showed a steady rate of organic matter accumulation regardless of baseline levels. Moreover, we observed a concurrent increase in labile carbon content in the 2-year ley treatment and positive reference, indicating improved soil nutrient cycling and ecological processes that facilitate soil carbon sequestration. Our results demonstrate that incorporating a 2-year diverse ley within arable rotations surpasses the COP21 global target of a 0.4% annual increase in soil organic carbon. These findings, derived from a working farm's practical and economic constraints, provide compelling evidence that productive arable agriculture can contribute to climate change mitigation efforts.