Well the soil classification is usually done on the basis of particle sizes and composition of soil.
<span>Clay </span>usually consists of particles less than 0.075 mm in size. It is a sticky soil and shows great changes in volume with variation in its water contact. It also shows considerable strength when air dried.
<span>Silt </span>has larger particles than clay and are mainly inorganic in nature. The particle size is less than 0.075mm and exhibits slightly plastic or non plastic behaviour.
Humus is soil consisting of dead and decaying organic matter. It is mainly organic in content but some inorganic particles may be mixed in it. The top soil in a tropical forest may be considered as humus.
Answer:
Plantae, Archaebacteria, Eubacteria, and potentially fungi. I say potentially because I am not 100% certain if all organisms falling under the category of fungi contain cell walls.
