Environmental- soil

• What is soil?

  It is an unconsolidated mineral or material on the surface of the earth resulting from and influenced by time, parent material, climate, organisms and topography.
• why is soil important?

  it is:

  The medium of crop production

  Producer and absorber of gases

  Snapshot of geologic, climatic, biological and human history

  waste decomposer

  source material for construction

  home to organisms

  filter of water and waste

  essential natural resource
• What is soil made of?

  soil is made of air, water, minerals and organic matter
• What are the different types of soil in Malta?

  Terra Rossa soil

  Xerorendzinas soil

  carbonate raw soil
• what is Terra-Rossa soil?

  It is a red type of soil. its parent material is mainly upper-coralline limestone, lower-coralline limestone and globigerina limestone. It has low humus content. it is shallow and stony.
• What is Xerorendzinas soil?

  It is rich in stone and chalk content, its parent material is globigerina limestone. it is low in humus content.
• What is carbonate raw soil?

  It is white in colour, its parent material is Blue clay. it is a young type of soil and contains little humus with the addition of lime and manure. It is good for farming
• What is parent material?

  The source from where the soil originates.
• what is climate?

  The sun, rain and wind determine soil formation
• what are Organisms to soil?

  Plants, animals and humans influence soil formation. The decomposition of plants and animals determine the organic content of the soil.
• What is topography?

  It means the shape of the land. Soils found at the top of a hill are usually less wet than those at the bottom, after rainfall. Soils facing the sun are dryer than those that do not.
• what are the layers of the soil profile?

  O horizon, A horizon, B horizon, C horizon, R horizon
• what does the layer O contain?

  contains humus. it is a dark type of soil due to the rich organic content
• what does the horizon A contain?

  It is called top soil and it is important for plant growth
• what does the horizon B contain?

  It is called subsoil and is rich in minerals.
• What does the horizon C contain?

  Contains weathered rock
• What doe horizon R contain?

  Layer of bedrock which is a very hard rock
• what is found deeper in the soil profile?

  Less organic matter

  less roots

  more weathered material

  more stone
• What is the difference between a soil profile and a soil horizon?

  Soil profile: vertical sequence of soil layers. Soil horizon: individual layer within a soil profile.
• what is soil erosion?

  The process of the removal and transportation of soil by wind or water.
• What is soil conservation?

  The practice of preventing soil erosion and degradation.
• What methods of farming causes soil erosion?

  up and down ploughing

  soil exhaustion

  rubble wall collapse

  overgrazing

  deforestation

  urbanisation
• what methods of farming cause soil conservation?


  Crop rotation, contour plowing, terracing, controlled grazing, afforestation
• what is up and down ploughing?

  This happens when the farmer ploughs up and down the slope leaving channels which soil is easily carried down due to gravity.
• when does soil exhaustion occur?

  This happens when the farmer grows crops in the same area without giving time for the soil to take enough nutrients reducing its fertility.
• what is rubble wall collapse?

  when rubble walls collapse the soil behind it can be easily carried away
• what is overgrazing?

  Excessive grazing of livestock on a particular area of land, leading to the depletion of vegetation and soil degradation.
• what is deforestation?

  when the trees are chopped down their roots will not bind the soil together and therefore, the soil can be easily eroded
• what is urbanisation?

  The building of houses and buildings result in the clearing of soil and land
• what is contour ploughing?

  this happens when the farmer ploughs across the slope making it difficult for soil to be carried downwards
• what crop-rotation?

  Its a planned activity where the farmer divides his land into four and grown the same type of crops in the same subplots and rotates them each year so the soil gets enough nutrients
• what is terracing?

  Terracing is a method of shaping and leveling land into steps
• what is controlled grazing?

  the farmer controls where and how much grazing happens in an area
• what is afforestation?

  when trees are planted the roots will bind the soil together