Subsurface irrigation – Root Feast System

Root feast – Root feast is a system which allows continuous feasting of water to tap root of the tree.

Objective

1. To study and design root feast system
2. Comparative study of root feast against drip irrigation with respect to evaporation , costing and maintenance

Components

1. PVC pipe
2. Bottle
3. Tube
4. Wick
5. Tree

For making the root feast system we have referred the data of Ashok Mathur Sir. He conducted their experiment of sub surface irrigation at pune in year 2019.

Process

1. Dig 18 inches hole deep and 4 inches wide in soil.
2. Place the PVC pipe in the center of hole.
3. Add 4 inches of soil at the bottom of the hole.
4. Place the open end of wick on the top of soil.
5. Plant the tree inside the pipe.
6. Add another 2 to 3 inches of soil over the roots of tree.
7. Fill the space between the hole and PVC pipe with soil till pipe is firm.

Rough Sketch of Root Feast system.

3 – 5 – 2022

Process

1. Firstly we have dig the hole in soil of about 45 cm deep and 5 inches wide in the soil
2. Then we have cut the PVC pipe (4 inches) into the pieces of 40 cm.

3. After that the soil filled at the the bottom of the PVC pipe.

4. Then we have placed the PVC at the center of the hole which was dig in the soil.

5. After that we filled the PVC pipe upto 15 cm by the combination of soil and compost.

6. Then we placed the root of tree and endpoint of wick which was connected to the bottle containing water on the top of soil which was placed in PVC pipe.

7. Further we filled the PVC pipe with soil upto the top of PVC pipe.

After setting all the setup the water from bottle was not going from the wick to the roots of tress by capillary method. Their was bubble coming in the bottle.

After discussing with Dixit Sir and Prasad sir we decided that the capillary action through wick does not take place until wick exposed to atmospheric pressure. Therefore we decided that to make the hole on the bottom of bottle and cut the bottle little on the top surface of bottle.

Changes made in the system

In first design the water from bottle is coming by gravitational force not by capillary method so we made the hole at bottom of bottle and made a cut on the top of the bottle.

9 – 5 – 2022

Then we drill the hole on the bottom of bottle and placed one end of wick in the bottle and another end on top of soil.

Readings of water applied with wick to tress

Day 1

Bottle 1 = 800 – 620 = 180ml

Bottle 2 = 800 – 460 = 340 ml

Bottle 3 = 800 – 540 = 260 ml

Bottle 4 = 800 – 690 = 110 ml

Bottle 5 = 800 – 710 = 90 ml

Day 2

Bottle 1 = 800 – 630 = 170ml

Bottle 2 = 800 – 560 = 240 ml

Bottle 3 = 800 – 570 = 230 ml

Bottle 4 = 800 – 670 = 130 ml

Bottle 5 = 800 – 670 = 130 ml

Day 3

Bottle 1 = 800 – 620 = 180ml

Bottle 2 = 800 – 510 = 290 ml

Bottle 3 = 800 – 580 = 220 ml

Bottle 4 = 800 – 650 = 150 ml

Bottle 5 = 800 – 610 = 190 ml

Day 4

Bottle 1 = 800 – 660 = 140ml

Bottle 2 = 800 – 420 = 380 ml

Bottle 3 = 800 – 440 = 360 ml

Bottle 4 = 800 – 510 = 290 ml

Bottle 5 = 800 – 660 = 140 ml

Day 5

Bottle 1 = 800 – 640 = 180ml

Bottle 2 = 800 – 530 = 270 ml

Bottle 3 = 800 – 560 = 240 ml

Bottle 4 = 800 – 670 = 130 ml

Bottle 5 = 800 – 700 = 100 ml

The water application rate from the bottle was less as water requirement of tamarind tree.

16 – 5 – 2022

Then after discussion we decided that the tube coming from bottle is less in diameter therefore the water coming from wick is blocking.

17 – 5 – 2022

Changes Made – In above system the diameter of hose pipe wad increased therefore the distance between inner surface of pipe and wick will increased and the water will freely flow from the wick because their will be maximum distance between the wick and inner surface of pipe.

Firstly we calculated the flow rate from the system outside it was 18 ml to 20 ml.

After installing the system the flow rate was again less as compare to experiment installed outside.

Then we calculated the water requirement of tamarind it was about 1.2 lites per day.

Therefore we connect 2 bottles to the system and filled 800 ml of water in bottle.

21 – 5 – 2022

After discussing with Dixit Sir and Prasad sir we concluded that we the area in the soil where the wick deliver the water gets saturated and after that the wick stop delivering the water from the bottle

23 – 4 – 2022

Then we installed the new design of root feast system.

Changes Made – In the above system we connected the T joint to the last end of hose pipe and two end of wicks was taken down from the two ends of Tee joint, from which two wick will deliver water at one time simultaneously

Costing

1. Drip irrigation – Drip irrigation system apply water near root zone in form of drops.

Components –

1. Drip line
2. PVC pipe
3. Dripper
4. Filter
5. Pump
6. End cap
7. Handle valve
8. Elbow joints
9. Tee joint

2. Root feast system

Components –

1. Bottle
2. PVC pipe
3. Hose pipe
4. Wick

Root feast system requires a labour for filling the water in water when the bottle gets empty.

Evaporation

1. Drip irrigation

According to the research paper if a dripper discharge 4 litres in 30 min the wetted width of it is 28.80 cm

The discharge of our root feast system is 0.5 lites

If a dripper discharges 0.5 lites for 30 min it’s wetted area will be 3.6 cm

Area – 3.14 × 3.6 × 3.6 = 40.69 cm square

Therefore according to pan evaporation

11.903 = 13.12 lit

40. 69 = ?

13.12 × 40.69 /11.903 = 0.044 litres

. = 44.85 ml/day/plant

If the drip irrigation is installed for 50 plants = 44.85 × 50 = 2.24 litres.

Maintenance

1. Drip irrigation

1. Check the working of the filters, leakage of pipe and fittings.
2. Check the lateral end caps and leakage through flush valve of submain.

2. Root feast system

1. The bottle gets squeezed after 4 to 5 week, so we want to change the bottle.
2. Wick gets thik when it remain in water for long time

Result

1. Tee joint system is suitable in all design of root feast system
2. Costing, Evaporation and maintenance is low of root feast system as compared to drip irrigation.

Concluding Note –