In 10 seconds? Cover crops have been protecting the soil for millennia and recent research confirms they can play a role in keeping carbon emissions in check, whilst reducing the need for fertilizer use.
Is there a measurable impact? Yes. By adopting cover crops and cutting back on soil erosion, the amount of carbon stored in the soil can increase by 21%, while inorganic nitrogen and phosphorous content can be boosted by 46% and 11%. The latter two are the main components of industrial fertilizers. If farmers have to use less, they save money. Land degradation associated with soil erosion estimated at 15 tons per hectare per year can cost farmers in the USA upwards of 500 billion dollars per year in fertilizer to sustain soil productivity.