Water Application Methods - Practices of Irrigation and On-farm Water Management - page 54

in water bills. The systems are vulnerable to blockage by organic matter, either in the
water supply or algal growth in the pipes themselves. Chemicals and filtering sys-
tems can be used to minimize these problems. In a wide spaced orchard, supplying
large trees with sufficient water can pose problems with a drip system, particularly
in the 4 weeks prior to harvest.
The advantages of drip irrigation are as follows:

• Highly efficient system

•

Saves water

•

Limited water sources can be used

•

Correct volume of water can be applied in the root zone

• The system can be automated and well adapted to chemigation and fertigation

• Reduces nutrient leaching, labor requirement, and operating cost

• Other field operations such as harvesting and spraying can be done while

irrigating

• Each plant of the field receives nearly the same amount of water

• Lower pressures are required to operate systems resulting in a reduction in energy

for pumping

The disadvantages/limitations of the drip system are as follows:

• High initial cost

• Technical skill is required to maintain and operate the system

• The closer the spacing, the higher the system cost per hectare

• Damage to drip tape may occur

• Cannot wet the soil volume quickly (to recover from moisture deficit) as other

systems

• Facilitates shallow root zone

• Needs clean water

2.3.6 Other Forms of Irrigation

Besides the above-mentioned methods, other categories of water application meth-
ods include the following:

• Hand watering

• Capillary irrigation

• Localized irrigation

• Trickle irrigation

• Micro-irrigation

• Subsurface irrigation

Hand Watering

The hand watering method is probably the most basic or earliest type of irrigation
method. Water is applied to the plant root zone (close to or directly at the root area)