A farm's productivity depends on nitrogen, whether it comes from organic or mineral sources. But the nitrogen cycle is leaky by nature, and some nitrogen is always lost. Nitrate-based fertilisers and precision farming are the best weapons against nitrogen loss and lack of efficiency.
Why it's important to control leaching
Leaching occurs when mobile nitrate from the mineral nitrogen pool is washed out of the root zone by heavy rainfall. This is both inefficient and harmful to the environment. High concentrations of nitrates contribute to the eutrophication of watercourses, which can cause algae blooms to develop and deplete oxygen levels in the water.
Causes of nitrate leaching
Large amounts of unused nitrogen in the soil, well-drained soil and heavy rainfall are the main causes of leaching. Reducing the amount of fertiliser alone won’t necessarily reduce residual nitrogen, but it could drastically diminish yield. The only solution is to ensure that nitrogen application is tailored to the needs of the crop.
10 ways to reduce nitrogen leaching
- Determine soil mineral nitrogen content by sampling.
- Use split application to adjust nitrogen availability to meet crop needs.
- Ensure balanced nutrition (P, K, S) to optimize nitrogen uptake.
- Develop a deep and extensive root system to capture available nutrients.
- Apply fertilisers and manure accurately across fields.
- Maintain buffer strips between cropped land and watercourses.
- Maintain green cover as long as possible to absorb excess nitrogen and make sure it is re-established rapidly after ploughing.
- Keep a porous soil structure to avoid surface run-off and sub-surface bypass flow on heavy soils.
- Check guidelines for the application of manure and fertilisers in autumn.
- Use robust, well-proven nitrogen recommendation systems such as Atfarms VRA and N-Tester solutions.
Get the tools you need to control leaching
- Digital precision farming tools, such as N-Tester and N-Sensor algorithm in Atfarm, measure a crops nitrogen demand, so that you can feed exactly the right amount in the right place.
- Your local Yara agronomist will help you establish fertilisation strategies that minimize leaching while optimizing yield on your farm.