Farm Environment, Sustainability and Natural Resource Management
Domain focus
Farm environment, sustainability and natural resource management tests nutrient cycling, emissions, water quality, biodiversity and how farming systems can reduce harm while remaining productive.
Core rules
- Nitrogen and phosphorus move through soil, water and air; losses cause eutrophication, ammonia emission and greenhouse gases.
- Methane comes mainly from enteric fermentation and slurry storage; nitrous oxide comes from nitrogen fertiliser and manure management.
- Buffer zones, correct application timing, soil testing and avoiding wet or frozen ground reduce runoff risk.
- Biodiversity measures include hedgerows, field margins, watercourses, woodland and reduced disturbance.
- Sustainability balances economic viability, environmental protection and social acceptability; it is not zero-input farming.
Worked example
A field receives 100 kg N/ha. Crop uptake is 70 kg N/ha, ammonia volatilisation 10 kg N/ha, leaching 5 kg N/ha and denitrification 10 kg N/ha. Residual N = 100 − (70 + 10 + 5 + 10) = 5 kg N/ha. The reasoning uses a simple mass balance. In practice, the residual may be immobilised in soil organic matter or lost later, so the balance identifies risk; it does not prove a specific loss pathway without measurement.
Traps
Do not confuse methane with nitrous oxide sources. Do not assume all applied nutrients are taken up by the crop. Do not spread slurry near watercourses or in poor conditions. Avoid claiming a system is sustainable just because it is organic or low-input.