Well, it's about weight disbursement. But there are ways to design structures that can hold larger loads. You can dwarf trees to grow fruit & nuts, you can design in natural light & insulate for temperature control. What really needs to be worked on is designing a superior multi-story structure that can be constructed on farmland so the remaining acreage can be reclaimed for wildlife. Just like a skyscraper, it can be designed to hold a lot of weight, be hurricane, flood, & tornado resistant, be thermoregulating. You could even "pipe in" light using refractive design elements. Just some of my thoughts.

@Nunya Yeah, I've thought of all that, too. Using fiber optics to pipe in light. Environmental controls, and water moisture reclamation. Incorporating livestock in order to gain some nutrients. A vertical conveyor system. I don't see any reason why it actually could not be a skyscraper type of building.

@bingst What type of structure do you think would work best & why? Just curious.

@Nunya Probably a skyscraper. Even one with a small number of floors as a pilot project would be informative. Say... 10 floors? I definitely think it should be mostly masonry and steel. In this case, I wouldn't want any kind of materials that would biodegrade, simply due to the high humidty levels, both from plants and animals. I'm not sure about exterior sheathing. Glass might be appropriate on the south face, but it kind of depends upon the location's climate. It might be better in some cases to have highly insulated (and opaque) walls all around, and bring in just the light.

By the way, it's the oxygen and carbon dioxide levels that would benefit from both plants and animals. Kind of a biosphere approach, but more about maintaining proper levels than self-containment. Of course with produce and livestock going out, key nutrients would have to be brought in. Plant biomass after harvest of annuals can be composted and/or digested, depending upon need.

It would be a highly integrated system.

@bingst Any articles you'd like to share on how best to accomplish this? I've come across some interesting ideas myself, but can't help but feel I must be missing something as it makes no sense that this is not being done already in most countries. The only truly efficient example I can find is in Singapore.

@Nunya It's been a very long time since I went looking for any info about it, so no, I don't have any articles on it. I'd have to search anew. Most if not all of the ideas I've talked about I came up with on my own.

@bingst Just curious, are you an architect or engineer?

@Nunya I've done some practical engineering, but no... not in any official way.