Urban as a part of Nature
Human civilisations carve out a huge portion of nature. Trees are cut. Wildlifes and animals are chased away or destroyed.
If we want to be able to live sustainably on this planet. Nature has to be integrated into human civilisations. Every single substance that is used to physically build human civilisation is extracted from the planet and is thus a part of it. Take away the exploitation of the Planet and you will see many businesses collapse on the spot.
In order to be sustainable, urban areas will have to have wildlife and greenery integrated. Trees produce oxygen essential for survival. Deforestation for financial gain is shooting ourselves in the foot. It is suicide.