Soil and vegetation

How soil is made up

Soil is a thin layer of loose material on the earth’s surface. It is vital for all land based life on earth- it is a vital natural resource.

Mineral Particles 45%

Small parts of rocks that have been broken down. Some particles are soluble which means that they dissolve in water.

5% Plant Remains

Dead leaves, plants, grass etc break down into a substance called Humus. This is a very fertile and helps to keep the soil together.

Water 25%

Water helps to dissolve the soluble minerals so that plants can absorb the nutrients.

Air 25%

Air is found in between the spaces of the particles. It also provides the plants with vital Oxygen and Nitrogen.


Many small creatures live in the soil, some we can see but many more that we can’t. They help to break down the plant remains to form the HUMUS.


How soil is made up

Common Soil Terms


This is what the broken down plant vegetation is known as. It is a dark, jelly like substance and is very good for the soil. The process is known as Humification.



This is when plant nutrients are washed down through the soil by heavy rain. After heavy leaching the nutrients gather at a place deep in the soil known as the hardpan. Farmers plough their fields to bring the nutrients up to the surface again.



Soil Types

Main soil types include-

  • Brown Soil (Most common soil in Ireland)
  • Podzols
  • Gley
  • Peaty Soil

Brown Soil

This soil is formed from broken down Deciduous leaves. This soil is very fertile because it contains a lot of Humus. Found in areas with moderate (Not too heavy) rainfall so leaching isn’t severe.


Brown Soil

Brown Soil profile

Brown Soil profile


This soil is formed under Coniferous forests. The soil is low in Humus and not very fertile. It is found mainly on the west coast where there is a lot of rainfall and so there is heavy Leaching.

podzolsPodzol soils

Podzol profile

Podzol profile