WATER

WATER RETENTION LANDSCAPES

Many of our modern land use management methods result in removing water from the land. Our urban environments are predominantly made of hard surfaces - roads, paved areas, roofs - and prevent the water from infiltrating into the ground. Water run-off from these surfaces is typically drained via a storm water reticulation system and it is quickly discharged into rivers or oceans. Modern agricultural methods often require tilling of the soil. Bare soils increase water run-off and often this water run-off is drained away from the fields to prevent damage to crops. Urban environments and many hectares of agricultural land are effectively draining and drying out the land by moving water quickly towards rivers and oceans, not allowing water to infiltrate into the ground to nurture soils and recharge aquifers.

Water retention techniques aim to slow the movement of water and allow the water to infiltrate into the soil. Water retention techniques result in improved soil hydrology and aquifer recharge. In addition, these techniques allow for soil biodiversity to thrive and diversify. This in turn results in more carbon being store in soils, creating a sponge effect. Soils with high carbon content infiltrate and retain more water than soils with less organic mater. 

At Wild Banana Design, we are certified professional water restoration practitioners specialised in water retention infrastructure. The certification process was achieved after rigorous specialist training by the global platform Water Stories led by Zach Weiss. Zach was the first person to earn the Holzer Practitioner certification directly by the acclaimed Sepp Holzer after a two year apprenticeship. 

Visit our services page for more information about our services, our process and our methodology.

THE WATER CYCLE

The water cycle is often summarised as water vapour rising from the oceans, also called atmospheric rivers, forming clouds that eventually cause precipitation. Once on land water run-off - water that does not infiltrate into the soil - ends up in streams and rivers and eventually returns back to the ocean. This picture although not entirely incorrect is an over simplification of the water cycle and leaves aside a few important factors. 

Transpiration

The first one is that a great contribution to the water cycle - water vapour in the air - is provided by vegetation transpiration. Transpiration is the release of water vapour by plants and trees through their leaves as part of their internal water circulation process. It is estimated that as an average only 39% of the precipitation received on land comes from the oceans. The majority, 61% derives from the land (Schneider et al. 2017). And more than half of this land derived atmospheric moisture comes from transpiration by plants (Jasechko et al. 2013; Sutanto et al. 2014; Wei et al. 2017).

Cloud and rain formation

The second important factor is that for clouds to form, condensation of water vapour particles in the air is required. Clouds are in fact a grouping of millions of water droplets. For the condensation of water particles to occur, a nuclei particle is required - cloud formation nuclei. There are a few nuclei particles known to condensate water vapour into clouds but one the most common and effective ones are organic volatile compounds released by plants. Once the cloud is formed, another nuclei particle - ice nucleating particle - is required to turn the millions of water droplets into rain drops. Some of the most common nucleating particles for rain formation are bacteria and fungi spores present on plant leaves. These microorganisms reach the clouds via water vapour particles as a result of vegetation transpiration.

What can we do to revive the water cycle?

The answer is simple but it requires a change in our mindset. In order to revive our water cycle, vegetation and soils must have a leading role. We should aim to increase vegetated biomass and the carbon content of the soils - we need spongy soils capable of infiltrating and retaining water for vegetation and other biodiversity to thrive.

References

The above information is extracted from leading scientific research on climate and the role of biology on rainfall. If you are interested in learning more about this the following are some reputable scientist that have done extensive research on this subject:

Cindy Morris - Senior Researcher and Scientist - Director of the Plant Pathology Research Unit at the French Department for Agriculture.

Millán Millán - Senior atmospheric scientist - Director of the Centre for Environmental Studies in the Mediterranean (CEAM) and one of the main environmental assessors for the European Union.

Walter Jehne - Soil microbiologist, climate scientist and researcher - Founder of Healthy Soils Australia and panelist at the United Nations Food and Agriculture Organisation conference in Paris - 2017.