First , I would like to thank everyone who contributes their knowledge and experience to this site.
A little background to help understand my question: I don't consider myself vegan as such, (meaning it's not an ethical decision but rather a health choice), but I don't consume any animal products except honey so my questions are more directed towards the energy input/output of animals in a closed system as it relates to plant crops only. My main protein sources come from peas, beans ,legumes nuts and seeds ,whole grains, greens. I have some experience with small flocks of chickens and Aquaponics.
Ideas and thoughts :
Growing plant proteins
Animals in systems for manure, pest control, etc. ( without the need for meat, dairy ,eggs .Is it worth it ? )
Green manure
Vermiculture
aquaponics (again, is it worth it for plants only ?)
* and most importantly, all the stuff I have never considered
Thanks so much in advance