Fertiliser industry, nutrient cycles and responsible use
≈ 50 minFertiliser industry, nutrient cycles and responsible use
The fertiliser industry applies equilibrium, energy, redox and materials chemistry to food production. Nitrogen, phosphorus and potassium are major plant nutrients, often summarised as NPK. Industrial ammonia is a key nitrogen feedstock and is made from nitrogen and hydrogen in the Haber process. Fertilisers can increase crop yield when nutrient availability limits growth, but over-application or runoff can contaminate water. Excess nitrate or phosphate can drive eutrophication: increased algal growth, decomposition and oxygen depletion can harm aquatic organisms. A credible evaluation weighs food security, cost, emissions, water quality, soil condition and affected communities rather than treating fertiliser as simply good or bad.
Work it through
A farm reports low crop growth and applies an NPK fertiliser after soil testing. Good practice matches nutrient dose to crop and soil needs, avoids application before heavy rain and monitors nearby water. If a dam later develops algal blooms and low dissolved oxygen, nutrient runoff is a plausible pathway to investigate, not a conclusion to assert without measurements.
Mastery target
Explain the role and production context of fertilisers, trace a nutrient-runoff mechanism and evaluate a farming decision with benefits, risks, stakeholders and evidence.
What is a likely consequence of excessive nutrient runoff into a dam?
Name the key chemistry term from Fertiliser industry, nutrient cycles and responsible use that best fits the explanation and visual model.
Which evidence best tests whether fertiliser runoff is affecting a stream?
Which statement corrects a common misunderstanding in Fertiliser industry, nutrient cycles and responsible use?