The pore space changes depending on recent weather and the degree of compaction. When it rains, water soaks in and pushes out the air. As the soil dries up, air replaces the spaces that previously were filled with water. Plants are adapted to a particular balance of water and air in a soil. That s why some plants are able to grow in wet areas along streams, and others prefer dry desert soils.
Air is pushed out, and there is less room for water to penetrate well.
Plant roots can t get enough air or water, and the plants may die. If the soil is poorly drained, the pore space stays filled with water for a long period, and plant roots may drown if they are not adapted to saturated conditions. Whenever possible, avoid compacting soils so you can maintain nature s sponge in good condition.