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Question 1
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- List three characteristics of each of specimens A and B
- List two precautions to be observed when applying each of specimens A and
- List two precautions to be observed when applying each of specimens A and B.
- State which of the specimens is recommended to improve clay soil.
Give two reasons for your answer. [3 marks] |
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This question was fairly attempted by the candidates. In 1 (a), most of the candidates were able to name the class of manure to which specimens A (Poultry droppings) and B (NPK 15-15-15) belong. However, in l(b), majority of the candidates were unable to list the characteristics of specimens A and B. Also, many candidates could not list the precautions to be taken when applying each of specimens A and B as demanded in 1 ( c).
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Characteristics of:
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Specimen A (Poultry droppings) It is bulky
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Rich in micro-organisms
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Contains many plant nutrients/improves soil fertility the nutrients concentration are fairly low
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Capable of binding soil particles together/improves soil structure has a bad smell
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Improves soil temperature
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. It is structure less/amorphous Tends to be neutral in reaction Low availability of nutrients
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Nutrients not easily leached/lasts longer in the soil Reduces soil erosion by improving soil structure Variable nutrient concentration
- Specimen B (N-P-K 15 -15-15) Granular in structure Has pungent smell
- Contains only few mineral nutrients
- The concentrations of these nutrients are very high The nutrients are fixed in definite proportion
- Not bulky in nature
- Does not reduce soil erosion Nutrients are readily available Hygroscopic
- Easily leached; does not last long in the soil
- Precautions to take when applying
- Specimen A (Poultry droppings)
- Should not be applied when fresh to crops on the field Must not be allowed to touch the plants
- Should cure properly before application/fully decomposed before applying Wash hands immediately after application
- Wear protective clothing
- Should be applied when soil is wet
- Specimen B (N-P-K 15 -15-15)
- Do not allow direct contact with the plant Do not apply when the soil is very dry
- When applying manually always wear gloves Wash hands immediately after application Do not apply to alkaline soils
- . Do not eat, drink or smoke when applying the fertilizers Do soil test to know deficient nutrient before applying
- Also in l(d), most of the candidates could not state which of the specimens (A or B) would be recommended to improve clay soil and give reasons.
- The extended answers are specimen A
- Reasons:
- It binds clayey particles together thus opening up/enlarging the pores
- It improves water percolation
- It improves aeration
- It improves soil fertility
- . It improves soil drainage
- It will improve soil temperature in clay soils
- It will enhance the release of locked nutrients and make them more available
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