Overuse of fertilisers in Spanish agriculture is creating serious environmental problems. Experts are warning in the newspaper El País that 70% of fertilisers used on crops are lost to the air, groundwater, and surface water. This waste is not only inefficient but also harmful to the environment.
The excessive use of nitrogen-based fertilisers, essential for crop growth, leads to contamination of rivers, lakes, and groundwater, causing algal blooms that can kill fish and disrupt ecosystems.
According to Estela Romero, a scientist from the Centre for Ecological Research and Forestry Applications (CREAF), the overuse of fertilisers is a “colossal waste.” Nitrogen from fertilisers seeps into the soil and water systems, leading to contamination. In extreme cases, like in the Mar Menor, fertiliser runoff has caused massive fish die-offs due to oxygen depletion. Additionally, the high levels of nitrates in fertilisers also impact the soil’s microorganisms and contribute to greenhouse gas emissions.
One of the most concerning issues is nitrate contamination in drinking water. When nitrate levels exceed 50 milligrams per litre, the water becomes unsafe to drink. In 2022, over 171 municipalities in Spain had water supplies exceeding this level, affecting 214,000 people, according to a report by Ecologists in Action.
Reducing fertiliser use: A challenge
Farmers are aware of the negative impact of excessive fertiliser use, but they face challenges in reducing their reliance on it. José Manuel Delgado, an agricultural expert, notes that farmers are required to follow specific fertiliser plans, especially in areas marked as sensitive to nitrate pollution. Good agricultural practices, included in the EU’s Common Agricultural Policy (CAP), aim to reduce this impact, but achieving real change remains a challenge.
Alberto Sanz Cobeña, professor at the Polytechnic University of Madrid, stresses the importance of applying fertilisers according to crop needs. Anything that the plants don’t absorb ends up in the environment. Farmers are now using tools, such as a fertiliser calculator, to determine the right amount needed for their crops, helping to minimise waste.
Looking forward: Sustainable solutions
The European Union is pushing for a 50% reduction in fertiliser waste by 2030, while maintaining crop yields. This goal includes reducing overall fertiliser use by 20%. However, achieving this will require significant changes in farming practices and support for farmers transitioning to organic methods. Shifting from traditional to organic farming is difficult and may initially lead to lower yields, but experts argue that with proper guidance and support, it’s possible.
In the long term, solutions like using urban wastewater for irrigation or planting vegetation in irrigation channels to trap nitrogen are being explored. These natural solutions, combined with agroecological practices, offer a path to reducing fertiliser waste while protecting both ecosystems and human health.