soil

soil

1. components of soil

   • mineral matter
     • largest component. made of broken down material EG sand/silt. provides soil with nutrients
   • water
     • helps plants to grow. dissolves nutrients+ plants can absorb
   • air
     • found in the spaces between soil particles. Essential for plants to grow. also enable's organisms to survive
   • Humus
     • dark jelly like substance rich in nutrients. formed by remains of dead plants. this is called Humification. helps the soil together and increases fertillity
   • living orgainsms
     • Earthworms and insects burrow through soil allowing air and water to pass through. this helps mix soil. microorganisms break down plants and creatures to form Humus which increases fertlity

2. formation of soil

   • parent rock
     • some rocks slow to break down- granite. some break down faster- limestone. rack affects characteristics of soil- limestone rock nutrients
   • living orgainsms
     • micro organisms such as bacteria and fungi help break down dead vegatation and creatures in soil. this forms Humus
   • vegatation
     • when vegetation dies, it is broken down bacteria and fungi help break down dead vegetation and creatures in soil. this forms Humus.
   • time
   • human activaty
     • can infunece the makeup and quality of soil. ploughing and fertilizing can make soil fertile. the removal of vegetation and overuse of soil can strip of nutrients and make soil less fertile
   • relief
     • the relief or shape of the land has an impact on the soil. highland areas tend to be write. this leads to leaching
   • climate
     • cold areas- freeze thaw action (slow) thin soil. warm areas- chemical (fast) deep soil. wet area- leaching. dry areas- dry

3. soil processes

   • erosion
     • soil is the rmoval of soil by water it is caused by removal of trees, exhastsing the soil and to much grasing
   • leaching
     • leaching happens in wet climates. to much water washes minerals and humus down through the A horizon where roots can't reach it. this causes the A horizon to be less furtile

4. podzols

   • brown soils
     • it is dark brown, once was covered by deciduous forest
   • grey olor. cold and wet areas and is formed by coniferous trees. limited amount of plant litter. heavy rainfall causes leaching and development of hardpans beneath the surface.