I'm a bigger proponent for agroforestry than other methods. Being that monocultures are the biggest catalyst of desertification, agroforestry, when implemented in industrial agricultural settings, has a higher dimensionality/impact.
I did not scientifically measure this, but anecdotes are a good place to start for grant applications, so I'll mention it anyway.
I'm trying to turn a compacted field back into a tiny woodland. It's still mostly horizontal at this point, but it's full of pillbugs and spiders and earthworms and the birds seem to love foraging in it. An hour ago I looked out the window and saw a finch pulling a spider off the side of my house, and it reminded me that one of the supposed tenets of polycultures is that you build up the food web and the food web will take care of the pests. Then it reminded me that I don't recall seeing this many birds the previous year.
I've temporarily drawn in the bird population from the surrounding area, by providing a richer hunting ground (more carrying capacity). Next year there will be a few more baby birds surviving to adulthood, then they'll be competing aggressively for all the other invertebrates in the area, dropping more fruit seeds everywhere they perch, which means more bugs and fruit and so on.
