Question: How much water would be in different types of soil.

Asaf Shnel answered on 10 Nov 2020:

The amount of water in a soil is something that changes constantly depending on how wet the climate is. But the amount of water a soil can hold depends of the proportions of clay silt and sand in that soil and the amount of organic matter too.
You can imagine the soil being composed of solid particles and empty space between the particles. That empty space can be filled with air or water when it rains.
Soils with a lot of sand will have less of that ’empty space’, or pore space as it is called, that can be filled with water. But sandy soils drain fast because the pore spaces are big and let the water flow freely.
On the other hand, soils with a lot of clay particles, which are much more smaller than sand, will have a lot more pore space that can be filled with water when it rains. But because these pores are small the water drains out much slower than a sandy soil.
Organic matter also increases the amount of water the soil can hold by increasing the amount of pore space in the soil.
In general, a sandy soil could have around 39% of pore space from the total volume of soil that could be filled with water, compared to a soil with a lot of clay that can reach around 55% and a peaty soil with a lot of organic matter can even have 80% pore space which can be filled with water when totally wet!!!