water table, water logging, salinity

• Water Table:

  Level of ground water is called water table. It is very easy to obtain ground water in foothills of mountains and difficult in desert areas.
• Water logging:

  The rise of the water table to the surface level is called water logging and the appearance of salty patches is called salinity.

  Water available all year.

  Crops given more water than they use.

  Water table rises to surface level.

  Fertilizers add to salts in water.

  Salts left behind / form a hard crust on surface.

  Soil becomes infertile / toxic.
• Salinity:

  Evaporation of water.

  Salt in irrigation water.

  Salts brought to surface.

  Unlined canals leak.
• Measures (to overcome the problem of waterlogging and salinity)

  1. Lining the canals.

  2. Planting the trees in affected areas.

  3. Installing the tubewells.

  4. Education to improve farming methods.

  5. Flushing out of salts by water from tubewells surface drains.

  The tubewells pump out water at high speed and keep the water level down. If the pumped water is fresh, it could be used for irrigation, e.g. in Punjab province. If pumped water is saline it would be drained into river or lake, e.g. in sindh which is drained into Manchar Lake.
• Q.1. Explain why waterlogging and salinity of soils causes problems to farmers.

  Ans. Reduces cultivable area / makes land un-usable.

  Reduces yield / damage crops.

  Reduces income / profit.

  Expensive to reclaim land.
• Q.2. Describe the appearance of the area S in photograph B

  Ans. Bare / no vegetation.

  Cracks / cracked mud.

  Pools of water.

  Saline water.

  White / mustard color.

  Edged with black / grey.
• Q.3 Name the project set up to control salinity.

  Ans Salinity Control and Reclamation Project (SCARP).