How to maintain the organic matter level in soil?

Maximise the annual green cover time: winter cropping and cover crops

Reduce cultivation intensity: low-till, micro-till, no-till

Retain crop residues in the field

Return residues if removed: mainly as manure or compost

Apply organic manures

Include grass leys in the rotation

Build your worm population: reduce cultivations, retain crop residues, avoid carbendazim based plant protection products

Maintain a good soil structure & avoid compaction: better soil structure = more root mass = higher carbon sequestration