Increasing crop yields

• Overpopulation increases the demand for food. increasing crop yield (the amount of crops available for sale) helps supply this demand
• Inorganic fertilisers provide minerals for plant growth, for example potassium nitrate and ammonium nitrate
• Excessive use of inorganic fertilisers can cause eutrophication
• Plants absorb nitrogen for growth
• When the plants die the nitrogen is released to the soil (nitrogen cycle)
• Farming removes plants so nitrogen isn’t released to the soil
• Crops are used as cattle feed. (Fodder) most nitrogen is used by the cow
• When the cow is slaughtered the nitrogen passes to the consumer
• Some nitrogen is released back into the soil through faeces
• Manure (faeces mixed with straw/organic fertiliser) improves soil structure (making it less compact)
• Manure contains microbes that break down organic matter, releasing nutrients like phosphorus and potassium
• Nitrate leaching occurs when excess nitrates dissolve in water and drain away from the field
• Excessive use of chemical fertilisers can lead to eutrophication - excessive growth of algae which depletes oxygen levels in lakes and rivers
• Organic farming uses natural methods such as composting and crop rotation instead of synthetic chemicals