Hello everyone. I have been studying Architecture the past 3 years and have recently come across this problem myself. I am sorry to say I think concrete is a disgusting man made construction material that has taken over the earth. There is far far too much of it in the world and if people keep carrying on the way they do then it will not take long for them to replace all the natural beauties of the world with unnatural concrete. Defend the stuff as much as you like, it is still always going to be unnatural. it can never replace the earths oxygen system (billions of trees it cut down to create space), nor the earthy soil that is hidden away underneath it. What if i told you that for the entire existence of the concrete ( a very long time) it lets of fumes which damage the environment but the human eye cannot see this. And as for the billions of concrete foundations in the soil, this definitely does contaminate the soil with unnatural processes, which then contaminates the worms etc, which then contaminates the chickens and birds and so on..
What everybody needs to do to overcome the situation and all the lies we have been fed to us over the past 200 years. is learn about the earths natural beauty. Hemp. it has over 50,000 positive uses and is the best thing the world. it has been used since the beginning of mankind, and even tho i have no hard evidence, due to all the lies and hiding of the truth, I strongly believe it was used to pour liquid stone and create the pyramids. I have to go now. but please, the whole world, need to address the problem we are all involved in and come together as one so we can tackle it together and go natural