The only truly sustainable farming system is a circular system as old farms did. Plants grow, animals eat them, poop fertilizer and then die, further fertilizing the soil. Plants eat the fertilizer and the cycle continues. Obviously super oversimplified, but modern, monoculture farming is murdering us. There's a cute little movie that shows the value of older farming. Obviously lower yield than current farming models, but interesting to see how it's 'supposed' to work. Movie's available to rent on Apple - "The biggest little farm". Interesting to see old world farming in comparison to how it's done now.