Home » Agricultural Science » Agricultural Science Theory (a) Define the term soil. [2 marks] (b)(i) List the four components of soil. [2…

Agricultural Science Theory (a) Define the term soil. [2 marks] (b)(i) List the four components of soil. [2…

(a) Define the term soil. [2 marks]

(b)(i) List the four components of soil. [2 marks] (ii) State the percentage of each component by volume. [2 marks]

(c) Describe the process involved in making compost using the pit method under the following headings: (i) materials; [2 marks](i ) preparation; [6 marks] (iii) storage [2 marks] 

Explanation

(a) Definition of soil: Soil can be defined as unconsolidated weathered materials found in the uppermost layer of the earth surface on which plants grow.

(b)(i) Components of Soil Mineral matter/inorganic matter, Water, Air, Organic matter/living organisms (ii) Percentage of soil components by volume

– Mineral matter = 45% ± 5

– Water = 25% ± 2

– Air = 25% ± 2

– Organic matter/living organisms = 5% ± 2

(c) Description of the process involved in makingcompost using the pit method:

(i)Materials: Straw/grass/weeds/saw dust/lawn clippings, Bamboo/ sticks/straws. Ash, Biodegradable household refuse/ crop residues. Human waste/Animal dung/Farm wastes, Water, Urine, Old compost, Lime/Phosphorus fertilizer/Sulphate of Ammonia, Tester/dip tick

(ii) Preparation

– Dig pit to a convenient size

– Put big pebbles or stones or short poles/elephant grass at the bottom of the pit.

– Fill the pit with lawn clippings, leaves, weeds and other vegetable matter, most of which must be chopped up and mixed properly. 

-Spread evenly on top urine, wood ash and animal dung, then sprinkle water

– Repeat the process until the level of the top of the pit is reached

-After one layer has been laid, sprinkle it lightly with lime and add handfuls of soil

– Repeat the sequence above to a convenient height – Insert the tester to test for decomposition. 

(iii)Storage –

-Protect from rainfall to prevent loss of nutrients/store under shed

– Protect from direct ray of sun which may destroy the microbes and bake the material.