Agriculture Questions and Answers - Form 3 Mid Term 2 Exams 2023

INSTRUCTIONS

• Answer all questions (50 Marks)

1. Define the term soil erosion (1mk)
2. Give four natural factors that encourage soil erosion (4mks)
3. Outline the steps followed in the development of a gully (4mks)
4. State four types of landslides (2mks)
5. Give four effects of soil erosion (4mks)
6. How does mulching help in soil and water conservation (3mks)
7. Highlight four structural measures used in soil and water conservation (4mks)
8. Outline four functions of trees in soil and soil conservation (4mks)
9. Name any three methods that may be used in water harvesting (3mks)
10. Explain Five cultural measures used in soil and water conservation (5mks)
11. The diagram below illustrates a micro-catchment. Study it and answer the questions that follow.
    
    1. Identify the type of micro-catchment above (1mk)
    2. State one use of the above structure (1mk)
    3. Apart from this type ,state two other types of micro-catchments (2mks)
12. Give four pieces of information contained in a land title deed (4mks)
13. Give four advantages of land consolidation (4mks)
14. Give four disadvantages of hedges(live fence) as opposed to other fences (4mks) 

MARKING SCHEME

1. Define the term soil erosion (1mk)
   • This is the process by which soil is detached, removed and carried from one place to another where it may not be useful.
2. Give four natural factors that encourage soil erosion   (4mks)
   • Steep slope
   • Light soil /sandy soil
   • High amount of rainfall
   • Barenness
   • High rainfall intensity
   • Strong slopes
   • Shallow soils
3. Outline the steps followed in the development of  a gully (4mks)
   • Movement of water from a water shed
   • Channel erosion caused by flowing of water
   • Widening of the channel
   • Scouring of the floor of the channel
4. State four types of landslides  (2mks)
   • Slump/slip
   • Debris slide
   • Debris fall
   • Rock fall
   • Rock slide
5. Give the effects of soil erosion      (4mks)
   • Remove the top soil thus lowering the soil fertility
   • Destroys soil structure and washes away he soil microorganisms
   • Causes siltation in dams and rivers
   • Sedimentation affects fishing
   • Destroys underground pipes and roads
6. How does mulching help in soil and water conservation  (3mks)
   • Prevent splash erosion
   • Reduce speed of runoff
   • Reduce evaporation
   • Increase organic matter and water retention
   • Increase water infiltration
7. Highlight four structural measures used in soil and water conservation (4mks)
   • Trash/stone lines
   • Bunds
   • Cut off drains/diversion ditches
   • Terraces
   • Gabions/porous dams
   • Dams and reservoirs
8. Outline four functions of trees in soil and soil conservation       (4mks)
   • Prevent the soil from splash erosion by reducing the force of raindrops
   • Provide shade and reduce loss of water through evaporation
   • Act as wind breakers thus reducing wind erosion
   • Roots bind soil particles together reducing its liability to erosion
   • Reduce speed of runoff thus minimizing its erosive force
   • Their leaves decay and form humus which increases water infiltration
9. Name any three methods that may be used in water harvesting (3mks)
   • Weirs and dams
   • Ponds
   • Roof catchment
   • Wells
   • Rock catchment
   • Micro catchment
   • Retention ditches/level terraces
10. Explain Five cultural measures used in soil and water conservation (5mks)
    • Grass strips/ filter strips
      • minimize speed of runoff water
      • traps soil reducing erosive forc
    • Cover crops-reduce impact of raindrops/splash
    • Contour farming-creates ridges of earth which hold water thus reducing runoff and prevent rill erosion
    • Grassed waterways-reduce speed of running water and traps soil
    • Mulching- Reduces speed of runoff and reduce impact of raindrops
    • Afforestation or reafforestation-Trees act as windbreaks, reduce impact of raindrop
    • Strip cropping-Reduces speed of runoff, traps soil particles from runoff
11. The diagram below illustrates a micro-catchment. Study it and answer the questions that follow.
    1. Identify the type of micro-catchment above  (1mk)
       • V-shaped/Triangular
    2. State one use of the above structure  (1mk)
       • Used to conserve water for plants during dry seasons /drought
    3. Apart from this type ,state two other types of micro-catchments (2mks)
       • Semi circular bunds
       • Trapezoidal bunds
       • Contour bunds/furrows/contour ridges
       • Planting bits
12. Give four pieces of information contained in a land title deed   (4mks)
    • Land parcel number
    • Size of the land
    • Name of the owner
    • Date of registration
    • Seal of the registrar
    • Condition if any
    • Place of issue
    • Signature of the issuing officer
13. Give four advantages of land consolidation   (4mks)
    • Proper supervision of land
    • Saves time and transport costs
    • Ease of accessing agricultural extension service
    • Proper planning and adoption of crop rotation programme
    • Soil conservation and land improvement
    • Construction of permanent structures
    • Title deed is used to secure loan
    • Weed, pests, and disease control is enhanced
14. Give four disadvantages of hedges as opposed to other fences (4mks)
    • Takes too long to grow
    • Occupy wide space hence not suitable for paddocking
    • Can be hiding places for thieves and rodents
    • Thorny species can injure humans and livestock
    • Laborious in trimming
    • Irregular growth may leave gaps an advantage to thieves