Let's talk about water

“When the well’s dry, we know the worth of water.” Benjamin Franklin

One thing we know for sure, as we regenerate soils we increase both the amount of carbon the soil holds and it's water carrying capacity. Both are vital for a healthy living soil and healthy nutritious plants. The huge diversity of micro-organisms that exist in healthy soils need the water to live in.

Whereas we aim to lock carbon in, water is more transitory, moving from one state or place to another. On operations with plant cover at all times, a vast majority will move from the soil to the plants, some being used in photosynthesis to make glucose, but the vast majority will act as a transport mechanism to take minerals and other plants substances from the roots to the leaves and then will exit the leaves via stomata as water vapour.

This water vapour helps cool down the climate around the plants so keeping temperatures suitable for growth. It also condenses sometime as ground level as mist in the early morning or higher up to form clouds. This moisture then being returned to the soil and the cycle starts again.

However, current traditional farming practices are drying out soils. Low organic matter and a lack of biological processes in many of these soils mean they have poor soil structure. This reduces the amount of water that they can hold and absorb. In Gabe Brown's Book "Dirt to Soil" he quotes that for every 1 % increase in soil carbon, the soil can hold between 17,000 and 20,000 gallons more of freshwater and the same will applies in reverse. On these poorer soils, when it rains you will see significant runoff carrying what should become green water into rivers (blue water) and then off into the sea. This water then being unavailable to plants and unable to refill underground aquifers.

Which when combined with deforestation is reducing the amount of freshwater available to both agriculture and us humans. The UN in 2018 stated that over 2 billion people live in areas that are experiencing water stress and by 2030 700 million people could be displaced by intense water scarcity.

We often talk about food security but I could argue that water security when looked from a global perspective is a much bigger threat. With mass migration, war and poverty all a result of lack of water and degrading soils.

This is why I am so passionate about holistic management and regenerative farming. The work that the Savory Institue is doing with regards to reversing desertification using livestock and managed grazing is building health soils in brittle environments and thus increasing the water holding and absorption capacity of these soils and in some places, there are now streams and ponds which did not exist a few years ago.

Regenerative agriculture and the principles of building soil health through maintaining cover on the surface, a diversity of species, no-till and keeping the crops growing as long a possible each year, keeps the local water cycle working, reduces runoff, holds more water in the ground and keeps the soil and the nutrients in the field and not in the rivers. This water and nutrients being then available to the plants and thus we see more resilient plant yields from health living soils.

By building soil health we also see that it's the ability to absorb rainfall increases significantly as shown below. On regenerative farms, you will see less flooding and less water stress. What you will not see but will be happening will be the refilling of aquifers.

I mentioned earlier forests and the role they play. Whilst reading "Cows save the planet" by Judith D. Schwartz I came across the biotic pump theory. It makes a lot of sense to me. What do you think? The following video explains it.

A report in the National Geographic in 2018 estimated that 75% of soils globally are degraded to some degree. Just think of the potential we have to capture more freshwater on land if we improve soil health through regenerative practices and also reverse deforestation.

A 1 % improvement in soil carbon equals at a minimum of 185 m3 / ha increased water holding capacity. There are 13 billion hectares farmed globally and if we improved soil carbon by just 1 %, then across the degraded land we could hold an additional 1803.7 billion m3. I am sure this would make a dent in sea level rise, water security and climate change.