I recently had a conversation with a friend comparing this desert to the desert of Las Vegas. Las Vegas, they said, was all sand, buildings and plastic "grass." Coming to Ruwais, then, it was refreshing to find more trees and grass than they had expected.
There is an extensive gardening and landscaping effort throughout each city I've visited in Abu Dhabi. Miles and miles of Palm trees line the highways watered by even more miles of black hoses that utilize desalinated water from the gulf and give gardeners from places like Bangladesh and jobs.
I have read some complaints about the amount of energy and water that is used to produce these green places in the desert and I'm not sure how to solve that problem, but every time I see these green places, I appreciate them. I'm not sure there's a way to measure, but I would bet it helps people stay sane and continue living here longer.