In designing an allotment to fit in with permaculture principles how does crop rotation work with the 7 levels especially since canopy and sub canopy plants tend to be trees/shrubs.

Should one not rotate crops at all ? Is it that when planting vegetables, the densities are so low and the variety of plants so great that reasons for rotation are eliminated ? ie. The build up of pests, depletion of key nutrients, etc.

Surely it makes sense to move the planting around into some sort of rotation scheme ?

Also when incorporating a no-dig principle, adding mulch/manure/compost, this doesn't work with potatoes and root crops ? So if I have my allotment, some of it growing roots/potatoes the other part no-dig how does that work ?

Am I mixing too many ideas here ?