Why Does Nature Reduce Stress?

There is plenty of empirical evidence that exposure to natural environments can cut down on subjective reports of stress. Chronic stress and the cascades that it creates in the body are known to have a number of bad consequences for health. So i would also wonder if just simple stress reduction were not a pretty large contributor toward improved health, comes from time and nature. Why is it that nature reduces stress? This is probably a harder question to answer, but there have been attempts. But at least there are some interesting ideas out there, even though they may remain unproven, yes.