Winning Measures

Healthy soil, sustainable water management, and effective nutrient management are all central objectives in the effort to prevent eutrophication. The 12 measures identified here stand apart not only for their ability to effectively curb nutrient runoff but for the environmental co-benefits they yield – such as biodiversity protection and climate change mitigation.

Measures for healthy soil

Soil erosion and degradation are common challenges on farms across Europe. When fertile topsoil is lacking, the risk of nutrient loading to nearby water bodies increases. Healthy soil has a porous structure, rich organic matter, good water retention, high biological activity, and enables more fruitful harvests.

1. Maintain year-round plant cover – On agricultural land, the highest erosion rates occur in crop systems where the soil is left bare for extended periods. Maintaining year-round plant cover protects the soil against erosion and reduces runoff of phosphorus bound to soil particles. It also helps to maintain organic matter in the soil and improves soil structure and microbiological activity.

2. Protect soil structure – Compaction adversely affects the air capacity, permeability, and water retention of the soil. It reduces root development and biological activity and leads to decreased crop yields. Diversifying crop rotation, using lighter machinery, and working the soil in dry conditions can help prevent compaction.

3. Use catch crops or intercrops – Catch crops and intercrops are used to bind nutrients that have not been used by the main crops and are released from the soil after harvest. Sown together with the main crop or after the harvest, they are left to be buried in the soil, or to serve as plant cover over the winter. This can help maintain organic matter in the soil, and reduce nitrogen leakage by absorbing nitrogen and then releasing it for the benefit of the next crops.

4. Add organic matter to the soil – More organic matter in the soil contributes to improved soil health and production capacity. It also helps to mitigate climate change by fixing carbon in the soil. Growing catch crops or intercrops, and mechanically adding dry cattle manure or compost are ways to incorporate more organic matter in the soil.

5. Maintain buffer zones – Buffer zones of perennial vegetation along major ditches, riversides, and lakes help to reduce erosion and the transport of nutrients and plant protection products to water bodies. These are especially useful on fields prone to erosion or flooding. Maintaining grasslands and other vegetation in riparian zones also enhances biodiversity.

MEASURES FOR SUSTAINABLE WATER MANAGEMENT

Excess water in agricultural areas raises the risk of nutrient runoff, while water shortage can have a devastating effect on crop yields. Measures that control water movement can help retain water and capture nutrients, forming areas for flood water and storage for irrigation. These measures also support climate adaptation by preventing large fluctuations between water excess and dry periods.

6. Construct wetlands – Constructed wetlands can reduce nutrient runoff from the surrounding fields in its catchment by absorbing nutrients and storing them in biomass and sediments. However, effective nutrient retention is only possible if they are well dimensioned and well-managed, and if organic matter is regularly removed to avoid accumulation. Wetlands may also prevent flooding during heavy rain, store irrigation water and provide biodiversity benefits such as breeding habitats for birds.

7. Manage water – Effective water management helps ensure good yields, nutrient balance, and water protection. Measures such as controlled subsurface drainage, two-stage ditches, flood meadows, natural stream beds, and irrigation water storage help solids settle on the banks of ditches or streams and slow down water flow at high peaks to prevent over-flooding. Vegetation enhances this effect while also reducing erosion along banks.

MEASURES FOR MANAGING NUTRIENTS

Employing measures that monitor the amount, timing, and methods of fertilisation are key to reducing nutrient losses and improving nutrient use efficiency.

8. Practice balanced fertilisation – Balanced fertilisation is the key to good plant growth and the efficient use of farm resources. Soil analysis provides information on what is needed. Fertilisation should be planned according to plant needs, yield potential, and the phosphorus status of the soil on the field. Nutrient balance calculations can help farmers estimate how efficient their nutrient use is during growth seasons. Over several years, such data provides a valuable overview of fertilisation plans so key improvements can be made.

9. Apply fertilisers at the correct time – When fertilisers are applied at the wrong time or in the wrong conditions, the risk of nutrient loss greatly increases. Manure and biogas digestate, similar to mineral fertilisers, should be applied to the fields during spring and early summer when growing crops directly take up nutrients. Adequate storage and spreading capacity are important factors that
allow for this.

10. Use careful manure application techniques – When manure is spread there is a risk of nitrogen and phosphorous loss to the water and air. These emissions contribute to the eutrophication of water bodies, acidification, and can also harm human health. This risk can be minimized through the use of incorporation, injection, or slurry acidification techniques. Manure spreading with incorporation or earthing equipment reduces the risk of nutrient leaching to surface waters by moving nutrients away from the water flowing on the soil surface.

11. Use manure in plant production – The use of manure or manure-derived fertiliser products on plant production farms has the potential of substituting mineral fertilisers. Furthermore, it can increase and improve the organic matter content in agricultural soils for carbon storage capacity.

12. Practice precision farming – Uniform fertilisation can lead to part of the field getting too much fertiliser, and another part too little. Precision agriculture equipment and techniques minimize resource use and the risk of over-application. By looking at data from different parts of the field, management activities can be adapted to local conditions. This type of site-specific farming has a great potential to increase nutrient use efficiency and reduce environmental impacts.