8 CLASS - BIOLOGY - FA 4 - LAB ACTIVITY

 

8 CLASS - BIOLOGY - FA 4 - LAB ACTIVITY

Aim:

To study the effect of deforestation on soil erosion and water absorption.

Materials Required: Two shallow trays or plastic boxes, Garden soil, Small plants/grass (for one tray), Water mug or bottle, Measuring cup

Procedure:

 

Two trays were taken and filled with equal amounts of soil.

In the first tray, small plants were grown to represent a forested area.

The second tray was kept without plants to represent a deforested area.

Equal amounts of water were slowly poured into both trays.

The flow of water and soil erosion were carefully observed.

The amount of water absorbed and soil washed away was noted.


Observation:

The tray with plants absorbed more water.

Very little soil was washed away from the tray with plants.

In the tray without plants, water flowed quickly and carried soil along with it.

The soil surface in the deforested tray became uneven.

 

Results and Discussion:

 

The experiment showed that soil without plants was easily eroded by water. Plants helped to hold the soil firmly with their roots and reduced water runoff. This proves that deforestation leads to soil erosion and loss of fertile soil.

 

Inference:

 

Deforestation increases soil erosion and reduces water absorption in soil, which can lead to floods, droughts, and desertification.

 

Precautions:

 

Equal quantity of soil and water was used in both trays.

 

Water was poured slowly to avoid disturbance.

 

Conclusion:

 

Forests play an important role in protecting soil and maintaining water balance. Cutting trees causes serious environmental problems.