Agriculture Reference
In-Depth Information
Fig. 2.2 Schematic layout of
a basin irrigation system
Basin
depending on crop and cultural practices. Basins need not be rectangular or straight
sided, and the border dikes may or may not be permanent. This irrigation technique
is also called by a variety of other names such as check-basin irrigation, level-
basin irrigation, level borders, check flooding, check irrigation, dead-level irrigation.
Basins may be of different types: rectangular, ring, and contour.
Basin size is limited by available water stream size, topography, soil factors,
and degree of leveling required. Basin may be quite small or as large as 15 ha or
so. Level basins simplify water management, since the irrigator need only supply
a specified volume of water to the field. With adequate stream size, the water will
spread quickly over the field, minimizing nonuniformities in inundation time. Basin
irrigation is most effective on uniform soils, precisely leveled, when large stream
sizes (relative to basin area) are available. High efficiencies are possible with low
labor requirements.
If it is possible, irrigate each basin individually when irrigating. To maintain
control with basin irrigation, divert the well discharge into the top basin until the
desired application is achieved. The total well discharge is then moved to the second
basin and the first basin cut so it drains into the second basin. This process requires
a certain amount of labor as the water “steps down” the field. This gives better
water control for application amounts and increases the amount of water available
for irrigation.
2.3.2.2 Suitabilities and Limitations of Basin Irrigation Method
Crop
Basin irrigation is suited to irrigate close growing crops (e.g., paddy). Paddy (rice) is
always grown in basins. Many other crops can also be grown in basins: e.g., maize,
sorghum, trees. Those crops that cannot stand a very wet soil for more than 12-24 h
should not be grown in basins.
Basin and border strip irrigations flood the soil surface, and will cause some soils
to form a crust, which may inhibit the sprouting of seeds.
 
 
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