Food forests should be considered when space is limited. When you need, or want to grow a lot of shit in a limited space, or want a somewhat more efficient system.
Thoughts:
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Spacing and species selection are important considerations. You don't want things too close together due to intra and Interspecies competition for light and nutrients. Regardless of what you plant, you got to make sure you have enough NPK for all your crops. Secondary and micronutrients need to be considered too. You have to really understand your plant requirements and pick ones that go well together to be as successful as you can. It can work if you just plant random crap; I'm just talking if you really want to go hard, look at nutrient supply and demands.
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I wouldn't consider any sort of agriculture carbon capturing. You're not building soil organic carbon unless your C inputs outweigh your output, and even then organic C readily breaks down, and some is lost. Don't get me wrong, organic amendments are great, but generally are used to replenish outputs (neutral, rather than positive).
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Most benefit will come from weed control (mulch) and water retention. The soil microbiome is kind of an after thought in that it takes a long time to establish what was there before we decided to plant/disturb the soil
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Don't be mortified of tilling. Some is good, esp. if you're incorporating crop residues.