Mole Drainage for Improving Salty Clay Shallow SalineWatertable, Egypt

摘要

An experimental field was conducted at El-Serw Agricultural Research Station, Agricultural Research Center, in the Northeastern Delta to study the effect of mechanical technique component tile drainage with mole drains on improving soil condition andwater table behavior in addition to its draw down rate. The experimental field consisted from drain spacing treatments: (i) No drains, (ii) thirty metre spacing and (iii) sixty metre drain spacing as well as secondary drainage treatments were mole drainsat 1.5 m spacing with 50 cm depth perpendicular on field drains. The mole drain treatments were: (i) no mole, mole and mole with hydraulic connections to tile drain.The treatments of tile drain spacing and mole combined with tile drains are highly effective on reducing soil salinity, Tile drains only or combined with mole lines realized a positive effect on soil desodification. The best treatment to improve soil condition was mole lines with hydraulic connection under 30 m tile drain spacing. The reduction in bulk density values was more pronounced in treatment of mole lines with hydraulic connection.Generally, results indicate that drainage treatments have an attractive effect on lowering the water table, for the most part under narrow spacing between drains combined with mole lines and hydraulic connection. Increasing downward water movement afterirrigation gives the chance for the effective root zone to dry, shrink and form water pathways.