Biosphere2 was an experiment to seal humans and plants i to a dome and not open it for some time.

Fungus and other pests destroyed some important plants and the eco system collapsed.

It had been built in the middle of a desert but urban expansion means the site is reasonably near housing now.

There were a bunch of photos of the dusty derelict interiors floating around a few years ago.

I kind of wish people would try again, just becuase.

I thought the biggest problem was the concrete. That is, soil microbes produced excess CO2, which would have been okay because the plants should have been able to photosynthesize it to O2, but instead the excess carbon dioxide reacted with the concrete, thus reducing the O2 levels.

Ah, here's a summary of the various things that went wrong, including details about the concrete: http://biology.kenyon.edu/slonc/bio3/2000projects/carroll_d_... .

It doesn't mention fungus, but does talk about other ecosystem problems (the pollinating insects died out, the morning glories took over, etc.).

Evidently it's not derelict anymore... the University of Arizon has owned it since 2011. Lookin' pretty cool!

https://en.wikipedia.org/wiki/Biosphere_2

If you're ever in Tucson, you should go for a tour. It's a fascinating place, and they've repurposed the facility to do a lot of worthwhile and interesting science.