Environmental Studies(ES)

ENVIRONMENTAL STUDIES

Lesson 7: Land resources

Factors affecting erosion

There are mainly three factors that will be affecting erosion

• Natural factors:
  
  
  1. Heavy rains on weak soil: Rain drops loosen soil particles and water transports them down hill.
     
  2. Vegetation depleted by drought: Rain drops are free to hit the soil, causing erosion during rainfall. Winds blow away the fine particles during droughts.
  3. Steep slopes: Gravity pulls harder: water flows faster, soil creeps, slips or slumps downhill.
     
     
  Sudden climate change:
  
  
  1. Rain fall: Erosion increases unexpectedly rapidly as rainstorms become more severe.
     
  2. Drought: Water dries up and the soil becomes a play ball of winds. A sudden rain causes enormous damage.
     
  3. Changing winds: Areas previously sheltered, become exposed.
     
     
• Human-induced factors:
  

1. Change of land: The land loses its cover, then its soil biota, porosity and moisture.
   
2. Intensive farming: The plough, excessive fertilizer and irrigation damage the land, often permanently.
   
3. Housing development: Soil is barred; massive earthworks to landscape the subdivision; soil is on the loose.
   
4. Road construction: Roads are cut; massive earth works, leaving scars behind. Not enough attention is paid to rainwater flow and maintenance of road sides.