Page 44 - Introduction to Agriculture by: Aqleem Abbas

Introduction to Agriculture Notes prepared by: Aqleem Abbas

It records or calculate amount of rain fall.

Irrigation methods.

Irrigation, artificial watering of land to sustain plant growth. Irrigation is practiced in all parts of
the world where rainfall does not provide enough ground moisture. In areas of irregular rainfall,
irrigation is used during dry spells to ensure harvests and to increase crop yields. Irrigation has
greatly expanded the amount of arable land and the production of food throughout the world. In
1800 about 8.1 million hectares (about 20 million acres) were under irrigation, a figure that rose
to 41 million hectares (99 million acres) in 1900, to 105 million hectares (260 million acres) in
1950, and to more than 273 million hectares (675 million acres) today. Irrigated land represents
about 18 percent of all land under cultivation but often produces over twice the yield of non
irrigated fields. Irrigation, however, can waterlog soil, or increase a soil's salinity (salt level) to
the point where crops are damaged or destroyed. This problem is now jeopardizing about one-
third of the world's irrigated land.

1. Surface irrigation
2. Sub surface irrigation
3. Sprinkle irrigation
4. Drip irrigation or trickle irrigation

Surface irrigation

In surface irrigation water is applied on the surface of soil.
Kinds of surface irrigation

1. Basin irrigation
2. Furrow irrigation
3. Border irrigation

Basin irrigation

In basin irrigation water is applied to the entire field for example supply of water to whole field.

e.g. barseem, shaftal, wheat.

Furrow irrigation

In furrow irrigation water Is applied to the plant rows in the small water channels. E.g. cabbage, maize
and tomato

Border irrigation

In border irrigation water is applied to the crops or field in small strips e.g. shafta. Agroforestary trees.