Observe the experimental set-ups A and B in which 120ml of water was made to drain through each of the different soils contained in the funnels. Use the exp...

Answer Details

Read the volume of water collected in each measuring cylinder. Let the volume collected under set-up A be x ml and the volume collected under set-up B be y ml. In each set-up 120 ml of water was poured through the soil.

(a) Volume of water collected

• Set-up A = x ml
• Set-up B = y ml

(b) Volume of water retained

Water retained = water added − water collected.

• Set-up A: \(120 - x\) ml
• Set-up B: \(120 - y\) ml

(c)(i) Percentage of water that percolated

• Set-up A: \(\dfrac{x}{120} \times \dfrac{100}{1}\%\)
• Set-up B: \(\dfrac{y}{120} \times \dfrac{100}{1}\%\)

(c)(ii) Percentage of water retained

• Set-up A: \(\dfrac{120 - x}{120} \times \dfrac{100}{1}\%\)
• Set-up B: \(\dfrac{120 - y}{120} \times \dfrac{100}{1}\%\)

(d) Better soil for crop production

The soil in set-up A is better for crop production. Reasons:

• It contains organic matter, which binds the soil particles and improves the soil structure.
• The organic matter is a source of nutrients for plant growth, and the rate of leaching of nutrients is lower in A than in B.
• It retains water better than B while still having moderate air space, so moisture is available to plant roots for a longer time.