Why is nature so healing to the human soul?

Sitting on the banks of Kosi river and listening to the sound of its rippling flow,watching the leaves fall aimlessly from tree tops and birds gliding high in the sky I revel in the serenity.In the midst of wilderness away from the maddening noise of humanity the internal monologue of the mind subsides.The mind is quite,the egoistic "I" shedding all the self-imposed trappings of the world.One is no longer self absorbed but is deeply aware of being a part of the whole,of belonging and realising that the same core energy is flowing through you as it does through the entire universe.There is no lonliness,discontent or fear.There is the just the calm realisation that your life is about understanding that you are a part of this whole, you will ultimately merge into it and be born from it again.One experiences the meaning of "Just Being".It is meditating with all senses being acutely alive.