Efficient use of irrigation water

Note

Different size jaltriptis can be made to suit your needs.

Plant

Rural women travel long distances for fuel, food, and fodder. This work can pose great hardship, especially in arid and semiarid regions where trees and crops are scarce. Irrigation is an obvious solution, but providing enough water to nurture crops and trees on dry, sandy soils is difficult. There are techniques and tools, however, which can help.

Jaltripti

Growing trees is difficult in arid and semi-arid regions, especially in high percolation sandy soils. A simple device called a Jaltripti can reduce the frequency of waterings and reduce the total amount of water needed, while ensuring a constant regulated supply of moisture to young trees.

Construction

The jaltripti consists of a double-walled earthen pot. It is made by placing one pot inside a larger pot. See box at left.

The base (but not the sides) of the inner pot is coated with paint, cement, or coal tar to keep water from passing through.

Method

- Dig a hole and bury the jaltripti up to the rim of its outer pot.

- Fill the inner pot with good soil.

- Transplant the sapling into the inner pot.

- Fill the space between the two pots with water.

- Cover this circular water reservoir with polythene sheet to reduce evaporation. Do not cover the sapling.

- Fill the jaltripti with water every week or so, depending on the season and the size of the pot.

Pitcher method

The pitcher method makes good use of water. It is best suited to dry areas with light soils, but can be adapted for use anywhere. It is particularly useful for growing melons, gourds, pumpkins, and other trailing plants.

- Dig holes 70 cm wide and 70 cm deep.
- Add 18 kg of composted manure to each hole.
- Add 18 kg of soil to each hole and mix well.
- Bury an earthen pot with the mouth of the pot at ground level in the middle of the bed.
- Fill the pot with water up to the brim.
- Cover the pot.
- Plant four seeds around the pot.
- Refill with water whenever the water level decreases.

Circular gardens

Circular gardens are best suited to drought areas and where land is scarce. They use little water.

Method

- Dig holes 30 cm in diameter and 30 cm deep.
- Build bunds around the rims of the holes.
- Plant seedlings inside the holes.
- Water close to the stem of the plant.

Sprinkler irrigation

This method is used for medium and large farms. It is more efficient on coarse texture soils, such as sand and sandy loams, which have low moisture-holding capacity. It is especially useful on undulating land and sand dunes.

The water is sprayed on the crop at a controlled rate. It can be used for almost all crops and is very popular for cash crops and some orchard crops.

Spray irrigation is advantageous on some soils with salinity problems. It leaches salt effectively, and promotes seedling emergence and growth.

The spray cools the crops during high temperatures and controls frosts during freezing temperatures.

Some sprinkler systems are portable. A system costing Rs 1520,000 to install can irrigate 5-10 ha in one crop season.

Drip irrigation

Drip irrigation involves the slow application of water, drop by drop, to the root-zone of a crop.

Water is used very economically, since losses due to deep percolation and surface evaporation are reduced to the minimum.

This system is suited to arid regions. Growing orchards on saline soil is possible using the drip system.

Sources: Ms. Chitra Mani, Mr C. V. Sheshadri, and CDRT Allahabad