Hm. Difficult question but the Kara people on Ukara Island (Tanzania) have an interesting way of managing their society in the face of limited land and resources.
New study drastically reevaluates the amount of trash in Europe's second largest river: 4,700 tons per year. Meanwhile, Pasig River in the Philippines are at 63,000 tons per year. The Rhine is 50 times longer than The Pasig, and has 15 times the water volume.
On the calefactory, or calefactorium, one of the very few heated rooms in a medieval monastery. It wasn't only to keep monks warm in chilly winters though, it was also used to keep the important munimentum, or muniment chamber dry and warm to save important records and archives from damp and mold.