Fertilisers
Biology: IB Diploma Higher Level, topic 8.1.6
Fertilisers
Fertilisers replace nutrients lost from the soil during harvesting and removing livestock to help maximise yields in agriculture.
Agricultural impacts on soil
- Agriculture leads to depleted levels of nutrients in the soil (e.g. nitrogen and phosphates).
- This is because when crops are removed for harvest, they are not decomposed and the nutrients are not returned to the soil for reuse.
- Removing livestock for slaughter also decreases nutrient levels because they are not replaced by decomposition.
Using fertilisers
- Fertilisers can be used to replace the nutrients (e.g nitrogen and phosphate) lost through agriculture.
- Increasing nutrient levels by fertilisers allows farming to continue without negative impacts on the crop or livestock quality.
Types of Fertilisers
There are two types of fertiliser:
Artificial fertilisers
- Artificial fertilisers (e.g. ammonium nitrate) are inorganic.
- Artificial fertilisers are produced specifically for replacing nutrients.
Natural fertilisers
- Natural fertilisers (e.g. composted food waste, manure) are organic.
- Natural fertilisers are taken from organic matter and used to replace nutrients.
Test yourself on Fertilisers
Which of the following statements about fertilisers are true?
Which of these is NOT a use of fertilisers?
What are the two types of fertiliser?
Which of the following statements about types of fertiliser are true?
Which of these is NOT a feature of natural fertilisers?