INDIAN GEOGRAPHY

Detailed explanation-1: -Basin irrigation is the most common form of surface irrigation, particularly in regions with layouts of small fields. If a field is level in all directions, is encompassed by a dyke to prevent runoff, and provides an undirected flow of water onto the field, it is herein called a basin.

Detailed explanation-2: -Check basins are useful when leaching is required to remove salts from the soil profile. The method enables the conservation of rainfall and reduction in soil erosion by retaining a large part of the rain in the basin to be infiltrated gradually, without loss due to surface runoff.

Detailed explanation-3: -Border strip, otherwise known as border check or bay irrigation could be considered as a hybrid of level basin and furrow irrigation. The field is divided into a number of bays or strips, each bay is separated by raised earth check banks (borders).

Detailed explanation-4: -Surface irrigation stands for a large group of irrigation methods in which water is distributed by gravity over the surface of the field (note: surface irrigation does not include spate irrigation). The three most common methods are basin irrigation, border irrigation and furrow irrigation.

Detailed explanation-5: -The check method of irrigation consists in making the area into square or rectangular plots surrounded by levees and irrigating each plot. An expression to estimate the deep percolation losses in such a system has been derived.