A. Relevance and sustainability context
A.1 Policy relevance
The N-surplus of the total N balance of agriculture (“farm-gate nutrient balance”) is an indicator that describes the loss potential of reactive nitrogen in the hydrosphere and atmosphere. It is an official environmental indicator in Germany that covers many environmental dimensions: High N surpluses signalise threats to ecosystems, air quality, climate and water bodies due to emissions of reactive nitrogen into the environment.
The value is used to monitor the sustainability strategy (target: 70 kg N/ha as a 5-year moving average). In the context of the bioeconomy, the total N balance can be used as a core indicator for the resource efficiency of biomass production.
Depending on the regional resolution, the indicator is of interest to environmental and agricultural ministries at federal and state level: Fertiliser legislation, evaluation of operational N efficiency and funding effects, progress monitoring of the target from the Sustainability Strategy.
A.2 Sustainability and / or comparative evaluation options
Today, the indicator is calculated from the national inflows and outflows of nitrogen in agriculture. Existing significant regional differences for the indicator are not visible (currently only visible for field balance – which is part of the total balance).
As an extension, the balances should be regionalised as the regional need for action to improve N balances is of interest (e.g. NUTS2 level).
B. Data availability
B.1 Stage of development
Nitrogen surplus in agriculture is a well-established indicator, which is reported for the German Sustainable Development Strategy.
Furthermore, the indicator is part of annual agricultural statistics (Table 0111260)
(∑Ninput – kg ∑Noutput) / area in [kg N/ha]
B.2 Data sources
https://dns-indikatoren.de/2-1-a/
B.3 Coverage over time and replicability
Every two years, the Federal Statistical Office reports in detail on the development of the achievement of this target.
The time span is from 1990 to today (n-2a).
B.4 Coverage across scales and sectors; compatibility
The indicator represents the agricultural sector and is reported in national resolution.
Regionalization could be generated based on model results (e.g. CAPRI). Due to the suspension of the Nitrogen Balance Ordinance, no extensive farm data is currently available.
C. Considerations for operationalization
C.1 Feasibility: Fit for monitoring
The indicator is considered very robust (methodologically sound, reliable, and fit for bioeconomy monitoring)
C.2 Institutions
The indicator is calculated by the Institute of Crop and Soil Science at the Julius Kühn Institute and the Institute of Landscape Ecology and Resource Management at the University of Giessen.
C.3 Future prospects
Regionalisation based on the existing models and data appears possible at any time. The inclusion of farm data does not seem to be a realistic option currently.
C.4 Costs, considerations and reproducibility
Only limited further costs for regionalisation as annually data and models already exist.
C.5 Potential for automation
Strong potential for automation annually as data and models already exist.
C.6 Presentation options and breakdown / sub-indicator needs
A bar chart is suitable for the national resolution. In the case of regionalisation, a representation as a map would be more suitable; trends could be indicated by additional symbols (e.g. one arrow per district).
C.7 Potential for scenario integration
As the N surpluses can already be modelled today, integration into future scenarios is easy to implement. Example for CAPRI modell:
Agora Agrar (fig. 27, p. 70)
C.8 Interlinkages and alignment with other monitoring activities
The EU bioeconomy-monitoring system does not include the indicator of a farm-gate nutrient balance. https://knowledge4policy.ec.europa.eu/visualisation/eu-bioeconomy-monitoring-system-dashboards_en
Agri-environmental indicators (AEI) track the integration of environmental concerns into the common agricultural policy (CAP) at EU, national, and regional levels. Farm-gate nutrient balance is not part of this indicator set
https://ec.europa.eu/eurostat/web/agriculture/database/agri-environmental-indicators
Further Comments:
Eurostat Definition of Gross Nutrient Balance explicitly as a balance of inputs and outputs to the agricultural soil. Common terms are also soil-surface / field or land balance[1]. Whereas in Germany a Gross Nutrient Balance usually describes a so-called farm-gate nutrient balance.
The EU Farm to Fork Strategy (EC 2020a) and the EU Biodiversity Strategy (EC 2020b) aim to reduce nutrient losses by at least 50 % without compromising soil fertility. In the future, the target will be described by the nitrogen use efficiency (NUE) indicator (N-input / N-output in %). The nitrogen use efficiency (NUE) is derived from the raw data of the Farm Sustainability Data Network[2] (FSDN). The FSDN plays a central role in monitoring, evaluating and shaping the Common Agricultural Policy (CAP) by analysing and modelling the sustainable performance of EU farms. No data is yet available as the new environmental variables were first included in the survey in 2025. A methodological description is provided in the Guidance Document for assessing NUE at farm level by the EU Nitrogen Expert Panel[3].
[1] https://ec.europa.eu/eurostat/cache/metadata/tmp/aei_pr_gnb_esms_4d.htm
[2] The Farm Sustainability Data Network (FSDN) is an EU survey collecting data of around 80 000 farms across the EU, representing 3.7 million farms and 90% of the agricultural production. FSDN builds on the long-standing Farm Accountancy Data Network (FADN) which is managed at the national level and compiled at the EU level.
[3] https://www.eunep.com/wp-content/uploads/2023/11/NUE-Guidance-Document.pdf