Planting legumes and grass between rows of corn appears to be an optimal, pollution-free way to rejuvenate nutrient depleted soil.
(Methods used as-of-date to address the issue involve burying fertilizer + waiting years to reap benefits, or, most commonly, annually spraying fertilizer over the land and watching the nutrients pollute rivers + oceans.)
https://phys.org/news/2025-01-crops-mulch-boost-soil-health.html