Soil

1.    In addition to the rock particles, the soil contains,

(i) air and water

(ii) water and plants

(iii) minerals, organic matter, air and water.

(iv) water, air and plants.

2.    The water holding capacity is highest in

(i) sandy soil

(ii) clayey soil

(iii) loamy soil

(iv) mixture of sand and loam.

3.    Match the items in Column I with those in Column II

Column I                            Column II

(i) A home of living organisms   (a) Large particles

(ii) Upper layer of the soil           (b) All kinds of soil

(iii) Sandy soil                                (c) Dark in colour

(iv) Middle layer of the soil         (d) Small particles and packed tight.

(v) Clayey soil                                 (e) Lesser amount of humus.

4.    Explain how soil is formed.

5.    How clayey soil useful for crops?

6.    List the difference between clayey soil and sandy soil.

7.    Sketch the cross section of soil and label the various layers.

8.    Razia conducted an experiment in the field related to the rate of percolation. She observed that it took 40 min. for 200mL of water to percolate through the soil sample. Calculate the rate of percolation.

9.    Explain how soil pollution and soil erosion could be prevented.

10.  Solve the following crossword puzzle with the clues given:

Across

2. Plantation prevents it.

5. Use should be banned to avoid soil pollution.

6. Type of soil used for making pottery.

7. Living organism in the soil.

Down

1. In desert soil erosion occurs through.

3. Clay and loam are suitable for cereals like.

4. This type of soil can hold very little water.

5. Collective name for layers of soil.