Question 4
(a) State one use of each of specimens K and L in the construction of fish ponds[ 2 marks ]
(b) Name four other items that are required in the construction of fish ponds. [ 4 marks ]
(c) State two ways of maintaining specimen K. [ 2 marks ]
(d) Describe two methods of applying specimen M in fish ponds. [ 4 marks ]
(e) State three effects of applying excess quantity of specimen M to fish ponds. [ 3 marks ]
Observation
This question was well attempted by the candidates. Most of the candidates were able to
state the uses of specimen K (Mattock) and specimen L (Shovel) in the construction of
fish ponds, name other items required for construction of fish ponds as well as state the
ways of maintaining specimen K (Mattock) as required in 4(a), (b) and (c). However,
majority of them were unable to describe the methods of applying specimen M (Poultry
manure) to fish ponds as required in 4(d).
Finally, majority of the candidates were unable to state the effects of applying excess
quantity of specimen M (Poultry manure) to fish ponds as required in 4(e).
The expected answers were:
4 (d) Methods of applying specimen M (Poultry manure) to fish ponds
Broadcasting
- It could be spread and mixed with bottom soil or thrown over pond water
surface.
- It is done before or after impoundment.
- Appropriate quantity is determined.
Bag/Sac method
- Manure is put in muslin/jute sac/bag and suspended in pond water (not
nylon).
- Nutrients move from bag into water
- It is done after impoundment or during rearing
- Bag is removed after use
Spot/side placement
- The manure is place at a particular spot in the pond.
- Nutrient leach out and dilute with water gradually.
(e) Effects of applying excess quantity of specimen M (Poultry Manure) to fish ponds
- Causes excessive algal bloom
- Could kill micro-organisms
- High pH of water
- High ammonia content of water
- Pollution of water makes environment unfit for fish.
- Soil becomes silted / high siltation
- Excessive algae/silt clogs fish gills
- Reduction of dissolved oxygen in water.
- High turbidity of water
- Causes disease outbreak in water.