| Nutrients are lost when crops are harvested | - When crops are harvested, they're removed from the field when they're grown rather than being allowed to die + decompose there
- So mineral ions that they contain, like nitrates, are not returned to the nitrogen or phosphorous cycle
- They're also lost when animals are removed from the land
- When taken elsewhere for slaughter or transported, the nutrients aren't replaced through their remains or waste products |
| Importance of fertilisers | - Adding fertiliser replaces the lost minerals, so more energy from the ecosystem can be used for growth
- Increasing the efficiency of energy transfer |
| Two types of fertilisers | - Natural (organic) fertilisers
- Artificial (inorganic) fertilisers |
| Natural (organic) fertilisers | - Consists of dead + decaying remains of plants + animals as well as animals wastes such as manure, slurry and bone meal |
| Artificial (inorganic) fertilisers | - Mined from rocks + deposits + then converted into different forms + blended together to give appropriate balance of minerals for a particular crop
- Compound containing the three elements, nitrogen, phosphorus, and potassium are almost always present |
| How fertilisers increases productivity | - Where nitrate ions are readily available, plants are likely to develop earlier, grow taller + have a greater leaf area
- This increases the rate of photosynthesis + improves crop productivity
- Nitrogen-containing fertilisers provides us with cheaper food |
| Organic farming | - Farming without herbicides/pesticides/inorganic fertilizer |
| Inorganic farming | - Using ammonium nitrate fertilizers |
| Organic farming/fertilizer | - Less soluble
- Lower concentration of ions
- Less leaching
- Micronutrients
- Harder to apply |
| Inorganic farming/fertilizer | - More soluble
- Higher concentration of ions
- More leaching
- No micronutrients
- Easier to apply |
