How rainforests keep our rivers flowing

Did you know that without the rainforests that cover the tops of our mountains, our creeks and rivers would not flow all year around?

As clouds move through high altitude rainforests, their moisture condenses on the massive surface area of the plants, wetting their leaves, branches, stems and trunks – a process known as ‘cloud stripping.’

The ancient rainforest with a layer of clouds in the distance viewed from Skyrail Rainforest Cableway

The ancient rainforest with a layer of clouds in the distance viewed from Skyrail Rainforest Cableway

Studies comparing the stem flow from cloud stripping with rainfall over the same period have found that plants at high altitude can harvest some 30-40% more moisture from clouds – even when it is not raining.

The Kauri Pine at Skyrail's Red Peak Rainforest Station laden in mist

The Kauri Pine at Skyrail’s Red Peak Rainforest Station laden in mist

These studies have also revealed that cloud forests contribute much more moisture to waterways than lower altitude forests because trees at higher altitudes grow slower and therefore use less of the harvested water. This is due in part to the lower temperatures at higher altitudes and the fact that the clouds block direct sunlight for a large part of the year. As a result, the excess water finds its way into creeks and rivers, hence the year-round flow.

Clouds rolling over the rainforest covered mountains of Tropical North Queensland

Clouds rolling over the rainforest covered mountains of Tropical North Queensland

Looking to the future, predicted temperature increases may cause the cloud base altitude to rise, reducing the area of cloud forests in the Wet Tropics. This, in turn, will impact the flow of waterways, particularly in the dry season. Cloud stripping is a great example of the many important ecosystem services that rainforests provide us with and another reason to appreciate and conserve these truly spectacular environments all across the world. Discover, encounter and immerse yourself in this fascinating ancient environment and experience it for yourself at Skyrail Rainforest Cableway.

Mike Gaia Skyrail Ranger and photographerAll images supplied by Skyrail Rainforest Cableway environment ranger and photographer Mike Gaia