The value of green space

Seems that our parks can actually help reduce stress and support our physical and mental health.  An article, Green space as a buffer between stressful life and health, references research done in the Netherlands on the buffering effect that green space has for people undergoing stress.  I know that a simple walk around the park can sure help me relax, especially when the park is green, not cold and white as it is now.

I wonder if cold white space adds to our stress levels? Perhaps only when were driving in traffic?