SOIL EROSIONGroup Members:● Candice Scott 11W● Octavia Lee 11W● Christina Ivey 11N

What is soil erosion?● Soil erosion refers to the removal of

topsoil faster than the soil forming process can replace it, due to natural, animal and human activity.

● The chief cause of soil erosion is human mismanagement.

Soil erosion is influenced by:● the texture and structure of the soil● the degree and intensity of the rainfall● the velocity of the wind● the degree of mankind’s interference

with the vegetation● the nature of tillage or crop cultivation● the degree of the slope of the land

Types of soil erosion● Sheet ErosionThis is the removal of a thin uniform layer of soil by water especially on sloping fields. This is caused by sheet flood or sheet wash.

Types of soil erosion● GullyingGullying is produced by the action of water on the soil which creates a deep gash or rill on the landscape, eventually forming gullies or channels. It results from intense runoff. It is concentrated on bare, steep slopes on clayey soils, especially if these are underlain by softer materials. Smaller channels are known as rill erosion.

Types of soil erosion● Wind ErosionWind erosion predominates when the land is bare, the particles become loosened are gradually blown away. the soil is removed by a process known as deflation. Wind erosion is more prevalent on flat surfaces and water erosion on on sloping surfaces.

Case Study: JAMAICA: Christiana, ManchesterCauses● Soil erosion has been caused by

overcropping and improper soil management. As a result of this the soil in the area is impoverished and farmers have a very hard time cultivating crops

Case Study: JAMAICA: Christiana, Manchester

● Soil erosion was quickened by farmers who cleared the hillsides of trees which resulted in gully erosion.

● Poor farmers planted ground provisions without fertiliser applications year after year. This led to deterioration of the soil quality and soil structure making it more susceptible to erosion. They then moved on to other plots to do the same.

● Additionally, in the cultivation of these ground provisions, a disproportionately large portion of the land is tilled and laid bare leaving it exposed to the elements.

Case Study: JAMAICA: Christiana, ManchesterMitigation efforts● The Christiana Area Land Authority

(CALA) was formed to help farmers cultivate crops on a more scientific basis and this correct the underlying causes of soil erosion. It was meant to raise the social and economic conditions of the farmers with a view to providings crops for export through responsible land farming.

Case Study: JAMAICA: Christiana, Manchester● Farmers were given larger plots of land and

advised on crop cultivation. This led to increased crop rotation, strip cropping, and contour ploughing.

● There was also an increase in the use of fertilisers and manure. Yields increased, farms were not abandoned and soil erosion was kept in check.

● An afforestation program for binding the soil and providing lumber was also set into motion. Large areas of badly affected land were reafforested.