Ok, so, I had this idea If you were to grow your own food and live on land as an overseer responsible for maintaining that land, then how much should you leave wild. I am coming from the premise that by allowing natural processes (like insect pollination, fungal and bacterial support, wild animals and undomesticated flora) to go untouched or nurtured your food supply will continue indefinitely. I am not alone in this philosophy by any means. Well, just by intuition, I guessed 80%. Actually, I initially thought to take a full quarter of the lands for my needs. I back-peddled from that because there is some lingering human greediness in me that I am lucky enough to be aware of. So, 80% untouched and 20% for my home, domestic animals and crops. Is this realistic? Lets see.
There are about 7.5 billion people on earth right now, give or take a few hundred million. The total land area of earth is about 57.5 million square miles according to quora.com. So, that makes about 130 people per sq. mile. There is 640 acres in a square mile. That makes .2 people per acre, or 5 acres per person on earth. That's not bad, considering how urbanized most of us are. Going with my intuition I started with here, that would be every person would get one acre to live on and grow food and leave 4 acres untouched.So, a family of five would get five acres to live on, grow food and develop for human use while leaving twenty acres.for wild plants and animals. Not to say they couldn't interact with that twenty acres, just don't interfere with it. A small town of 10,000 would leave 50,000 acres alone, for every city of a million we leave 5 million acres of natural habitat and so on Is that viable? According to this guyin the article below it is๐.
http://www.farmlandlp.com/2012/01/one-acre-feeds-a-person/
It may come to pass. Lots of factors in changing peoples minds