Mapping regional agricultural nitrogen fluxes for water and climate protection policy (RELAS II)

Background and Objective

In 2018, the European Court of Justice convicted the Federal Republic of Germany for failing to implement the Nitrates Directive (Case C-543/16). Many areas in Germany have nitrate levels in groundwater above the legal threshold of 50 mg/l. The requirements for fertiliser management in agriculture were tightened in 2020 by the amendment of the Fertiliser Ordinance. In order to identify the need for corrective measures in nitrate-polluted areas at an early stage and to prevent negative developments in areas that are not yet contaminated, a comprehensive monitoring system is to be set up in Germany that will enable statements to be made at short intervals on the effectiveness of the measures taken: monitoring of the Fertiliser Application Ordinance (in short: impact monitoring).

In the predecessor project RELAS, we began to set up the impact monitoring system. To this end, we established a comprehensive database that is fed with agricultural administration data, among other things. On the other hand, the AGRUM Germany model network, in which we are involved with the Regionalised Agricultural and Environmental Information System for Germany (RAUMIS), has been further developed for use in impact monitoring. Based on the nutrient inputs into water bodies modelled with AGRUM, the medium to long-term impact of reduction measures can be estimated.

In the RELAS II project, we are continuing the work from RELAS. We are focusing on further expanding the database so that we can represent the temporal progression of nitrogen and phosphorus nutrient pollution using time series. We are also further developing the AGRUM model network with the aim of mapping nutrient flows even more precisely, for example by explicitly taking organic farming into account.

Target Group

Policy makers (European Commission, Federal Government, Länder), agricultural and water management authorities, farm managers, environmental organisations, farmers' associations, interested members of the public.

Approach

Like its predecessor, the RELAS project, RELAS II is also coordinated by the Thünen Institute of Rural Studies. It is divided into the following sub-tasks:

1. Continuation and expansion of the database
2. Continuation of nutrient flux modelling using the AGRUM model network and methodological improvements, including explicit consideration of organic farming in nutrient balancing (Thünen Institute) and the residence times of leachate in groundwater cover layers (project partners).
3. Provision of results to the public, input for the annual report to the European Commission.

The large amount of input and output data is collated and managed in the central database at the Thünen Institute. To ensure the continuity of monitoring, routines are being developed that allow for recurring data evaluations, analyses and input for reports from the Federal Republic of Germany to the European Commission, providing both authorities and the public with detailed environmental information on the nutrient situation.

Data and Methods

Where possible, data from the following sources is acquired, processed and collated as a basis for the data:

IACS (Integrated Administration and Control System), HIT database, test farm statistics, animal disease fund, data from the administrative enforcement of the Fertiliser Application Ordinance, the Farm Manure Transport Ordinance, the Sewage Sludge Ordinance and the Bio-waste Ordinance.