Soils that contain a lot of clay have small pores and usually drain very slowly. These soils can become waterlogged if there is a lot of rain. Structure Soil texture and pore space influence the structure of a soil. Soil structure is determined by the clumping together of individual soil particles and is a result of physical, chemical and, often, biological processes which occur within the soil. Burrowing animals help to break up and aerate soil.
Human activities can also affect soil structure.
When dried, most of the pore spaces are filled with small soil particles. Frequent movement of vehicles over a dry soil will also eventually compact the soil and decrease the amount of pore space present. Soils without much pore space are dense. They have very little room for soil oxygen, absorb less water, and are more difficult for burrowing animals and roots to get through. Plants do not grow as well in compacted soil.