| Popis: |
LEVEL and low-gradient border checks for irrigating field crops are used where irrigation water is limited, where periodic leaching of salts is required, and where maximum use of rainfall is desired. Level basin irrigation has been used for centuries, especially for rice irrigation. In northern Italy where rice is one crop in the rotation, level basins are used for irrigation of other farm crops. These systems briefly described by Mead (5) * are still in use today. Petrov (7) described similar systems on natural slopes in the Golodnaya Steppe where land slopes range from 0.05 to 0.25 percent. |
