Morgan Irons patented “Ecological System Model” is pretty cool — although deceptively simple. U.S. patent No. 9,970,208 — focusing on space agriculture.

Claim 1:

A system for a self-sustaining and resilient human habitation on the Moon and Mars and for food security and climate change mitigation anywhere on Earth, comprising:

a habitation zone where humans are quartered;

an agricultural zone providing 700 square meters of food growing space per human; and

an ecological buffer zone approximately three times the area of the agricultural zone that contains a wild growth of plants and provides the remaining ecological services that Earth life needs to live self-sufficiently and resiliently.