The Indus Plain.

• The River Indus and it's tributaries drain the Indus Plain throughout most of Punjab. This is known as the Indus Plain.
• The narrow strip of land on either side of the river is known as the active flood plain
• The active flood plain is inundated almost every year.
• The Old flood plains cover the area between the alluvial terraces and the active flood plain. These are only flooded when there is heavy monsoon rainfall. The Old flood plain is covered with old alluvium which was deposited in the past.
• The surface of the alluvial terraces is flat and has a south west slope. These terraces are considered ideal for agriculture with the help of irrigation.
• Some alluvial terraces are the Sandal Bar in the Rachna doab, the Ganji Bar in the Bari Doab, the Nili bar in the Bari Doab and the Kirana Bar in the Chat Doab.
• The Bahawalpur plain is also an alluvial terrace.
• Alluvial terraces are areas of higher ground between rivers formed by erosion of old alluvium.
• A Doab is the land between 2 rivers at their confluence. When the river enters a mature valley, a number of topographical features are formed due to erosion and deposition.
• Some topographical features of a Doab are the levers, active flood plain, old flood plain, scarp and alluvial terrace.
• The high population density of Doab areas is due to some topographical features like:
• The active flood plain is flooded nearly every year, making it ideal land for crops that require a lot of water such as rice and sugarcane.
• Meander flood plains and cover flood plains are good locations for arable farming in fertile areas, while poorer soils can be used for human settlements.
• There is a well developed link canal irrigation system in Doab areas, leading to a continuous supply of water throughout the year.
• The bar uplands are safe from flooding, making them ideal locations for farming and human settlements, transport links, industrial estates, storage of agricultural raw materials and markets.
• The Doab between the Indus and Jehlum is the Sindh Sagar doab
• The Doab between the Jehlum and Chenab is the Chaj Doab
• The Doab between the Chenab and Ravi is the Rachna doab.
• The Doab between the Ravi and Sutlej is the Bari doab
• Ravines are small rivers
• Alluvial fans are multiple ravines.
• The area around and between Alluvial fans are Piedmont Plains.