Environment Science Lab Soil Planning Lab

Hypothesis:- Due to automobile movement on Sohna Road the texture, ph and the water content of soil maybe different. The soil samples are taken 1 metre, 2 metre and 3 metre from the road. According to me the texture, ph and the water content will be different because the soil that is present 1 metre away from road will be getting most affected because automobile movement will be the highest at 1 metre distance from the road other than 2 metre or 3 metre. The soil will be most affected on 1 meter because of the heat emitted by the vehicles. This will make the soil dry at 1 metre. Vehicles on the road enter the soil present at 1 metre because of no embarkments present on the road. Because of this the soil gets disturbed.

The water content might be low at 1 metre distance from the road because the automobile movement will be high and therefore the texture and ph and water content will be getting changed from time to time. The soil samples taken from 2metre will have different texture and the water content might be more because the soil there is not getting more affected than the soil present at 1 metre. And thus the Soil at 3 metre from road will be having the highest content of water and thus it can be said that the soil in different areas of road at a certain distance will have different soil texture, ph and water content. The pH of the soil will be basic because some vegetation was seen.

Variables:

1) Controlled Variables:

Time of collection of samples

Method of collecting samples

2) Independent variables: Distance from the road

3) Dependent: Amount of pH, soil texture and the water content in each soil present.

Materials required for testing Ph:-

1) 3 Long test tube (145mm) and 3 bung’s

2) Test tube rack.

3) Barium sulphate.

4) BDH universal indicator solution and pH meter

5) Spatula.

6) Distilled water

7) 30cm3 pipette.

8) Measuring tape

9) Tent pegs for marking after every 1 m

Materials required for soil texture:

1) Three 500 cm cube measuring cylinder.

2) Three samples of soil of 100 cm cube each.

3) 300 cm cube water for each measuring cylinder.

Materials required for measuring water content:-

1) Soil sample taken from 1m, 2m, 3m.

2) 3 Crucible.

3) Balance accurate to 0.1 gm.

4) Thermostatically controlled oven.

5) Thermometer reading up to 150degree c.

6) Desiccator.

7) Tongs.

Procedure:

The soil sample was collected from 1m, 2m, 3m distance from Sohna road. Measuring tape was used to mark the distance from the road. After every 1m a peg was used to mark the end point. The topmost layer of soil was taken and was craped by using a shovel. The soil was collected in three different trays and the time of collection was 10 am to 10.20 am in the morning. The soil samples were taken in the morning because the soil has moisture present at that time.

1) For testing the Ph of the soil sample.

1) Add about 1 cm of soil to the first test tube which has the soil sample taken from 1m. Also add 1 cm of barium sulphate, which ensures the flocculation of clay particles that remain in suspension.

2) Do Step 2 for the other 2 soil samples taken from 2m and 3m.

3) Label the test tubes as A for 1m, B for 2m, C for 3m.

4) Add 10 cm3 of distilled water and 5 cm3 of BDH universal indicator solution to all the three test tubes. Seal the test tubes with the Bung. Shake vigorously and allow contents to settle for 5 min.

5) Compare the colour of liquid in the test tube with the colours on the reference colour chart and read off the corresponding Ph.

6) Also compare the colour of all three test tubes.

7) Observe the Ph of all the three soil samples and compare.

Ph of all the three samples from 1m, 2m, 3m being tested

2) For observing the soil texture:

1) Add the soil samples to the measuring cylinder’s and cover with water.

2) Shake the contents vigorously.

3) Allow the mixture to settle out, according to density and surface area of particles, for 48hrs.

4) Measure the volume of the various fractions of soil samples.

3) For measuring the Water content of soil:-

1) Weigh all three Crucible dish while still empty. Record the mass (a).

2) Add a broken-up soil sample to the dish and weigh. Record the mass (b).

3) Do step 2 for 2m and 3m soil also.

4) Place the dishes with the soil sample in the oven at 110oC for 24 hrs.

5) Remove the soil samples from the oven and cool in a desiccator.

6) Weigh the samples when cool and record the mass.

7) Return the sample to the oven at 1100C for a further 24 hrs.

8) Repeat stages 4 and 5 until consistent weighing are recorded (Constant mass). Record the mass (c).

9) Calculate the percentage water content as follows:

When soil is added in measuring cylinder and water is added and it is shaken. The level seen in the measuring cylinder was 400 ml. After 48 hrs the level was 300 ml. This is because the air in between the soil particles is replaced by the water and thus the level decreases. This also shows that the soil is more sandy.

After conducting this we get the constant mass for all three soil samples. For 1meter the constant mass is 126.66, for 2 meter the constant mass is 125.98, for 3 meter the constant mass is 125.89 gm’s. The “4th heating” gives the constant mass of each sample.

Soil Distance from the road

Analysis: The Ph of all the three soil samples doesn’t have much difference between them because the samples taken are from one land but from different distances. The texture of the soil is different in all the three cases. At 1m most number of layers are observed and as the distance increases the number of layers are getting less. But 2 m and 3 m away from sohna road shows the same number of layers but with different thickness of each layer of soil. Maybe silt soil was observed in the first layer because of the fine particle size. The water content is different for all the three cases. The water content is decreasing as the distance from Sohna road of soil sample taken is increasing. This is because the soil which is near to the road had more number of layers then the soil which was away from the road. Seeing the soil texture the soil taken from 1m distance from the road had silt soil which is very fine. This shows that the ability of soil 1m away from the road had more capacity of holding moisture. The samples taken from 2m and 3m from road had only 2 layers and no layer of silt soil was present, thus these layers didn’t have capacity of holding moisture. So the water content is decreasing as the distance was increasing away from the road.

Conclusion: My analysis does not support the hypothesis. The pH is almost the same at every level. The ph is basic as mentioned in the hypothesis. The soil texture hypothesis is proved right as the texture of the soil is different in all cases. The water content of soil is high at close distance and very low at distance from sohna road . The soil sample near to the road has more ability to hold moisture because of the fine soil particles as compared to the coarse sandy soil which has better aeration but poor water holding capacity.

Errors and Improvements:-

1) The pH of the soil samples taken is not appropriate. Only one reading of each soil sample has been taken which is not appropriate.

2) At least five reading of each soil sample could have been taken.

3) The Temperature in those 3 areas from where the soil sample was taken could have been measured.

4) The Time taken to conduct the experiment should not have been much because of the air would dry the loose soil and thus appropriate readings will not come.

5) Light intensity could have been measured on all the three places from where the soil sample was taken because light is directly proportional to heat.

6) In the experiment to check for texture after 48 hrs the soil was not shaken well and the soil profile was not in a straight line so the readings were difficult to take.