To Study Soil Samples From Two Different Sites and Analyse Their Different Properties Such as Texture, and Moisture Content

Importance of Soil Sampling

Soil is an essential natural resource that provides a foundation for plant growth and is a critical component of many ecosystems. However, soil properties can vary greatly depending on the location and environmental factors. The texture and moisture content of soil, for instance, are two fundamental characteristics that play a vital role in determining soil quality and its ability to support plant growth.

The objective of this experiment is to analyze soil samples from two different sites and investigate the differences in their properties, specifically their texture and moisture content. By examining the physical and chemical characteristics of the soils, we can gain a deeper understanding of the ecological conditions at each site and the potential impact on plant growth and other soil-dependent organisms.

Through this experiment, we hope to learn more about how variations in soil properties can impact ecosystem health and inform soil management practices that promote sustainability and the preservation of our natural resources.

Table of Contents

• Aim

• Apparatus

• Theory 

• Procedures

• Observations

• Precautions

• Lab manual questions

• Practical based questions

Aim

To analyse different soil textures, moisture content, pH, water holding capacity and based on this the type of plant that grows in different soils.

Apparatus

1. Tile

2. Beaker

3. Funnel

4. Burner

5. Dropper

6. Crucibles

7. Petri Dish

8. Glass Rods

9.Test Tubes

10. Wire Gauze

11. Filter Paper

12. Distilled Water

13. Mortar and Pestle

14. pH Paper Booklet

15. Measuring Cylinder

16. Universal pH Indicator Solution

17.Tin Box with a Perforated Bottom

18. Weighing Scale or Electronic Balance

Theory

Soil is the top weathered layer of the Earth's crust that has been influenced by plants and animals. A soil profile is formed by a vertical section through this zone; in each soil profile, there are usually several distinguishable layers or horizons that allow different types of soil to be identified. Mineral particles, organic matter, water, and air are all present in all soils. The combinations of these determine the texture, structure, porosity, chemistry, and colour of the soil.The components of a soil, as well as their proportions, can help us determine its productivity and the best use for that soil. To describe and differentiate soil types, several soil properties that can be easily tested or examined are used.

Procedure: To Study the pH of Soil Samples Taken from Different Sites:

1. Collect all soil samples in different beakers.

2. Pour some water into them and stir them.

3. With the use of a funnel and filter paper, filter this soil solution and pour them into different test tubes.

4. Use a dropper and pour a few drops of universal indicator. 

5. Observe and note the changes occurring that will detect the pH of the soil. 

Observation

The colour of the soil solution in the test tube changes when the universal pH indicator is applied. The pH colour chart can be used to monitor these colour changes. The pH of roadside soil is 7, while the pH of garden soil is 6. Most plants thrive on soil with a pH between 6.0 and 7.0.

Procedure: To Study Ttextures of Different Soil

1. Collect 50  gm of soil.

2. Insert the soil sample that has been obtained into a measuring cylinder that is clean and dry.

3. Now add a small amount of water to the same measuring cylinder and thoroughly shake.

4. Wait for the particles to settle down by leaving the equipment alone for a few minutes.

5. Watch how the measuring cylinder changes after a while.

6. In the measuring cylinder, the dirt particles will begin to stack up.

7. Keep track of these layers' thickness.

Observation

Draw the corresponding percentage of the soil components using a soil textural triangle (silt, clay & sand). The lines that cross as a result indicate the type of soil.

Procedure: To Study Moisture Content of Different Soil Samples

1. Take at least two (or more) soil samples for comparison.

2. Collect the samples in crucibles. 

3. Place them in a weighing machine and weigh them.

4. PLace it over a bunsen burner for the water to evaporate.

5. Now weigh the crucibles again to measure the dry weight. 

Observation

The sample with the bigger difference between the starting and final weights has a higher moisture content. Lower numbers indicate a relatively low moisture content.

Procedure: To Study Water Holding Capacity of Different Soil Samples.

1. Collect soil samples and transfer these into mortar and pestle.

2. Grind these until turned into fine powder.

3. Weigh the entire contents of the tin box.

4. Now, add the powdered soil into the tin box.

5. Use the glass rod to press and tap the box, so that the soil is uniformly layered.

6. Now, the weight of the tin box is measured and to be recorded.

7. Next, take two glass rods and place them parallel to each other. Ensure that the distance between the two is not long.

8. Position the tin on the two glass rods in such a way that the bottom is in contact with the water.

9. The complete setup should be left undisturbed until the water seeps through the upper surface of the soil.

10.Now, remove the tin and allow all the water to flow out from the bottom.

11.Wait until no more water percolates from the tin.

12. Now wipe the bottom dry and use the weighing machine to note down the weight.

13. Calculate the two different readings to know the water holding capacity of the given soil samples.

Observation

The ratio of the amount of water contained by the soil sample to its dry weight yields information about the soil's ability to hold water.

Precautions

1. Make sure the apparatus to be used is dry and clean.

2.Recording of weights must be done correctly.

3. The soil samples should be of the same weight.

4. Take samples of soil from different locations.

5. Make sure to label the test tubes and other apparatus correctly. 

Lab Manual Questions

1. How deep should the soil be dug for analysis?

Answer: The soil should be dug 30 cm deep. It's this region of the soil which contains the main nutrients that are absorbed by the plants and makes it easy to detect its characteristics. 

2. How would you define soil structure?

Answer: The gathering of soil particles into a structure is called a soil structure. The way that individual soil granules (particles) join together to create aggregates controls it. It consists of the spacing between soil particles and how they are arranged. It has a significant impact on biological, agricultural, and construction activities and depends on the soil's origin.

3. How would you define soil profile?

Answer: Several soil horizons comprise a soil profile. These soil horizons are nothing more than horizontal strata parallel to the soil's surface that may be distinguished from one another by a unique set of characteristics brought about by the soil-forming processes over time.

4. How does soil texture affect soil drainage?

Answer: Clay particles are extremely small. They pack and clump tightly as they dry when wet. Allow to dry and harden. They do not absorb water when packed like this.

Sand is the polar opposite. Particles that are large. Water flows right through.

Viva Questions

1. Mention layers of soil from top to bottom.

Ans. O horizon, A horizon, E horizon, B horizon, C horizon, R horizon

2. Define soil profile. 

Ans. The vertical stretch of soil from the ground surface down to where it meets the underlying rock is known as the soil profile.

3. What is the study of soil called?

Ans. The study of morphology of soil is called pedology.

4. Which indicator is used for analysis of pH of soil?

Ans. Two types of indicators are used depending on the basis of the ph of soil. For soil of pH between 5.0 to 6.2, Chlorophenol red is used and for soil of pH 6.0 to 7.2, Bromothymol blue is used. 

5. What tools or equipment are required to study properties of soil?

Ans. Some soil analytical equipment include push probes, hammer probes, bucket augers, etc.

6. What is the classification of soil based on its physical properties?

Ans. Alluvial soil, black soil, red soil, and yellow soil, desert soil, laterite soil, forest soil, and mountainous soil are the many types of soil that can be categorised based on how they were formed, their colour, and their physical and chemical characteristics.

7. What is the practical use of soil analysis?

Ans. Improved soil quality depends on the important information provided by soil analysis. A farmer may quickly modify fertilisation to meet the needs of the soil and the crop by keeping track of the precise amount of soil nutrients.

8. How does the texture of the soil affect water retention?

Ans. When compared to soils with larger sand particles, soils with smaller particles (silt and clay) have a larger surface area, and a soil with a larger surface area may hold more water. In other words, fine soil, which has a high proportion of silt and clay particles, has a greater capacity to hold water.

Practical Based Questions

Question 1. Which soil has the maximum water holding capacity?

1. Sandy Soil

2. Loamy Soil

3. Clay Soil

4. Red Soil

Answer- (C) Clay Soil

Question 2. Which soil has the minimum water holding capacity?

1. Sandy Soil

2. Loamy Soil

3. Clay Soil

4. Red Soil

Answer- (A) Sandy Soil

Question 3. Which is the soil surface which gets frozen due to cold?

1. Vermafrost 

2. Permafrost

3. Iceberg

4. Arctic berg

Answer-(B) Permafrost 

Question 4. Deep cracks are formed in hot weather due to which type of soil?

1. Yellow soil

2. Laterite soil

3. Black soil

4. Alluvial soil

Answer- (C) Black soil

Question 5. Factor(s) which affect the soil

1. Climate

2. Temperature

3. Humidity

4. All the above

Answer- (D) All the above 

Question 6. Which soil horizon consists of minerals?

1. A

2. B

3. C

4. All the above

Answer- (B) B 

Question 7. Which of the following is constituted by rock particles and humus?

1. Soil

2. Weathering

3. Humus

4. Gravel

Answer- (D) Gravel

Question 8. Which soil is best suited for cotton?

1. Black soil

2. Red soil

3. Laterite soil

4. Loamy soil

Answer- (A) Black soil

Conclusion

1. The proportion in which the soil separates to form the mineral component of the soil is defined by soil texture. 

2. Sand, clay, and silt are the three types of separates.

3. Soil permeability is a broad term that refers to the soil's ability to transmit water. 

4. It is partly determined by texture, with sandy soils having higher permeability than clay soils, and it can be altered through soil management.

5. The most important effect of soil pH is on ion solubility, which affects microbial and plant growth. 

6.Most crops benefit from a pH range of 6.0 to 6.8 because it corresponds to optimal solubility of the most important plant nutrients.