Sand does not hold water because there is no organic matter to hold water and because the spaces between particles is large. Approximately 50 percent of the soil is made of pore space . Of course when it rains or during a drought these percentages change drastically. Show how weather patterns affect the air and water percentages. Water and air in the soil is very important to the plants and animals that live in this ecosystem.
Water carries the nutrients to the plants.
Both water and air are necessary for life and growth processes of plants and animals. Plants and animals breathe. Plants consume carbon dioxide through their roots and animals take in the oxygen.