Answer to Question #228903 in English for Sne

Question

Second year hydrology student class of 2019 carried out a field experiment of different soil groups. Their objective was to test the soils for their texture, structure and consistency. Assume that the THREE samples collected from the field were composed of; Clay loam soils, loam an sand. (a) Describe the procedure(s) you would use to collect the same soil samples in an area of 400 square meters?

(b) Discuss the results they obtained in each sample in terms of texture, structure and consistency.

Answer 1

As hydrology students, we would use the following procedure when collecting different soil samples from an area of 400 square meters.

1. Divide the field into different homogenous units based on visual observation.

2. Remove the surface rubbish at the sampling spot.

3. Drive the auger to a plough depth of 15 cm and draw the soil sample.

4. Collect at least 10 to 15 samples from each sampling unit and place them in a bucket.

5. Mix the samples thoroughly and remove foreign materials like roots, stones, pebbles, and gravel.

6. Reduce the bulk to about half to one kilogram by quartering or compartmentalization.

7. Collect the sample in a clean cloth or polythene bag.

8. Label the bag with information like your name.

(b) Texture indicates the relative content of particles of various sizes, such as sand, loam, and clay in the soil. To get the texture of our three samples of soil, we mixed each sample with water and these were the results after rubbing the different samples between our fingers; one of the samples felt gritty an indication that it was sand soil, another sample had a smooth feel meaning that it was loam soil and the last sample had a sticky feel meaning it was clay soil.

Soil structure refers to the way soil particles group together to form aggregates.

After studying a sample of undisturbed soil in my hand and see how each individual unit of soil lines up, the following were the results; clay loam soils have Prismatic and columnar structures. Clay soil has columnar structures and sand soil has Granular and crumb structures.

Soil consistency is the strength with which soil materials are held together or the resistance of soils to deformation and rupture.

I measured them using wet, moist, and dry soil samples. The following were the results; clay loam soils have a higher LL and PL than non-colloidal clays. Clay soil has high LL and PL and sand soil had no plasticity, and their PL= 0.