If a water body becomes overly enriched with minerals and nutrients the excessive growth of algae can be induced. This process may result in oxygen depletion of the water body. Nitrate leaching is often the reason for eutrophication.

Surplus nitrogen from organic or mineral fertilizer can leach as nitrate (NO3) into the groundwater (potential drinking water) or be released as greenhouse gas (N2O) and ammonia (NH3) into the atmosphere and contribute to climate warming. Nitrate is microbially converted into nitrite (NO2) which may harm the human cell oxygen supply especially in babies. In the environment, a surplus of nitrogen can cause eutrophication of water bodies, lead to acidification of soils and disrupt the ecological balance.

Nitrogen fertilizer related environmental problems and mitigation measures are discussed on global, European and country level. Several European member states are above the set emission targets and are considering nitrogen stabilizer as an effective mitigation measure.  

The stabilization of nitrogen in agricultural soils is a key element. With its innovative urease and nitrification inhibitors, BASF offers solutions to improve nitrogen use efficiency by limiting nitrogen losses. Urease and Nitrification inhibitors are powerful and easy-to-implement tools to actively reduce NO3-, NH3- and N2O-emissions.


Eutrophication in AgBalance

In AgBalance the Nitrogen-emissions into the three different compartments (air, soil and water) are reflected and their potential to cause damages to the environment is calculated.

For both marine as well as freshwater eutrophication the proliferation rate of algae and their respective potential to damage the aquatic system is calculated using the EUTREND model of Struijs et al. (2009)1 .

Terrestrial eutrophication is assessed with the model of Accumulated Exceedance (Seppälä, Posch, Johansson, & Hettelingh, 2006)2. The model calculates the potential of a substance to cause terrestrial eutrophication in its equivalent to mols of nitrogen (N).

Different sources of nitrogen are taken into account when using AgBalance to calculate the eutrophication potential like fertilizers, natural emissions coming from field and soil as well as nitrogen emissions from water (e.g. irrigation).

For more details on how the eutrophication potential is calculated check the pdf with the technical documentation.

Environmental Impact Assessment

Technical documentation

1 Struijs, J., Beusen, A., van Jaarsveld, H., & Huijbregts, M. (2009). Aquatic Eutrophication. Chapter 6 of ReCiPE 2008: A life cycle impact assessment method which comprises harmonised category indicators at the midpoint and the endpoint level. Den Haag: Ministerie van Volkshuisvesting, Ruimtelijke Ordening en Milieubeheer

2 Seppälä, J., Posch, M., Johansson, M., & Hettelingh, J.-P. (2006). Country-dependent Characterisation Factors for Acidification and Terrestrial Eutrophication Based on Accumulated Exceedance as an Impact Category Indicator. International Journal of Life Cycle Assessment, 11(6), 403-416.