Pollution of ground-and surface waters with nitrates from agricultural sources poses a risk to drinking water quality and has negative impacts on the environment. At the national scale, the gross nitrogen budget (GNB) is accepted as an indicator of pollution caused by nitrates. There is, however, little common EU-wide knowledge on the budget application and its comparability at the farm level for the detection of ground-and surface water pollution caused by nitrates and the monitoring of mitigation measures. Therefore, a survey was carried out among experts of various European countries in order to assess the practice and application of fertilization planning and nitrogen budgeting at the farm level and the differences between countries within Europe. While fertilization planning is practiced in all of the fourteen countries analyzed in this paper, according to current legislation, nitrogen budgets have to be calculated only in Switzerland, Germany and Romania. The survey revealed that methods of fertilization planning and nitrogen budgeting at the farm level are not unified throughout Europe. In most of the cases where budgets are used regularly (Germany, Romania, Switzerland), standard values for the chemical composition of feed, organic fertilizers, animal and plant products are used. The example of the Dutch Annual Nutrient Cycling Assessment (ANCA) tool (and partly of the Suisse Balance) shows that it is only by using farm-specific “real” data that budgeting can be successfully applied to optimize nutrient flows and increase N efficiencies at the farm level. However, this approach is more elaborate and requires centralized data processing under consideration of data protection concerns. This paper concludes that there is no unified indicator for nutrient management and water quality at the farm level. A comparison of regionally calculated nitrogen budgets across European countries needs to be interpreted carefully, as methods as well as data and emission factors vary across countries. For the implementation of EU nitrogen-related policies—notably, the Nitrates Directive—nutrient budgeting is currently ruled out as an entry point for legal requirements. In contrast, nutrient budgets are highlighted as an environment indicator by the OECD and EU institutions.

The hot summer of 2018 posed many challenges with regard to water shortages and yield losses, especially for agricultural production. These agricultural impacts might further pose consequent threats for the environment. In this paper, we deduce the impact of droughts on agricultural land management and on water quality owing to nitrate pollution. Using national statistics, we calculate a Germany-wide soil surface nitrogen budget for 2018 and deduce the additional N surplus owing to the dry weather conditions. Using a model farm approach, we compare fertilization practices and legal restrictions for arable and pig breeding farms. The results show that, nationwide, at least 464 kt of nitrogen were not transferred to plant biomass in 2018, which equals an additional average nitrogen surplus of 30 kg/ha. The surplus would even have amounted to 43 kg/ha, if farmers had continued their fertilization practice from preceding years, but German farmers applied 161 kt less nitrogen in 2018 than in the year before, presumably as a result of the new implications of the Nitrates Directive, and, especially on grassland, owing to the drought. As nitrogen surplus is regarded as an “agri-drinking water indicator” (ADWI), an increase of the surplus entails water pollution with nitrates. The examples of the model farms show that fertilization regimes with high shares of organic fertilizers produce higher nitrogen surpluses. Owing to the elevated concentrations on residual nitrogen in soils, the fertilization needs of crops in spring 2019 were less pronounced than in preceding years. Thus, the quantity of the continuously produced manure in livestock farms puts additional pressure on existing storage capacities. This may particularly be the case in the hot-spot regions of animal breeding in the north-west of Germany, where manure production, biogas plants, and manure imports are accumulating. The paper concludes that water shortages under climate change not only impact agricultural production and yields, but also place further challenges and threats to nutrient management and the environment. The paper discusses preventive and emergency management options for agriculture to support farmers in extremely dry and hot conditions.

Intensive animal production, vast amounts of biogas plants, and the spreading of manure and digestates, exerts strong pressure on water quality in the German federal state of Lower Saxony. Catch and cover crop (c&c) cultivation is seen as one measure to inhibit nitrate leaching into soils, and to prevent water pollution with nitrates. A document analysis was carried out, covering the time span of 1992 to 2020, and the findings were combined with available quantitative data of the same period, and with GIS analysis. From 1994 to the year 2020, the acreage of subsidized c&cs increased from ca. 10,000 ha to ca. 380,000 ha. In addition, there was an acreage of unsubsidized c&cs of about 100,000 ha declining to 50,000 ha. In comparison, the acreage of arable land remained at approximately 1,880,000 ha. We found that c&cs did not contribute substantially to water protection for the following reasons: the design of the measure, control of farmer’s actions, and the antagonistic trend due to the increase in animal numbers and biogas plants. The development of c&cs over time and space reveals that frame conditions and management requirements of cultivating c&cs need to be well designed to be effective and efficient (with regard to N reduction and reduction of costs). It is vital to coordinate all programs and schemes in one region. From our evaluation, we conclude that a measure such as c&c cultivation, which is simple to introduce and easy to control, should be implemented over winter as a mandatory measure in order to achieve a greater uptake. Additionally, result-based measures could complement this scheme, as there is a strong link between subsidy level and the success of the measure.

Carbon farming has become an increasingly prominent concept in European climate and agricultural policy, particularly in the context of efforts to strengthen carbon removals from the land sector. In parallel, the European Union adopted the Carbon Removals and Carbon Farming Regulation (CRCF) in 2024, adding a new certification-based governance layer to an already dense landscape of public agricultural support instruments and diverse private initiatives. This article examines how this evolving policy field is perceived by national experts across eight EU Member States. Drawing on expert survey data collected in 2023, we analyse expert perceptions of carbon farming relevance, the potential and barriers of different practices, the status of monitoring, reporting and verification, and expectations regarding private initiatives. The results indicate that carbon-farming-related practices are currently supported mainly through existing CAP instruments rather than through coherent stand-alone carbon-farming strategies, and that inventory visibility of these measures remains limited and highly heterogeneous across countries. We interpret these patterns as indications of policy layering, in which new governance instruments are being added to established agricultural and climate policy architectures, without changing the existing policy structure. The type of layering varies by dimension: while some complementarities between CAP and CRCF incentives for farmers exist, the absence of reliable demand structures for CRCF credits and structural incompatibilities between CRCF certification and national climate accounting systems point towards an inefficient outcome and counter-productive layering, respectively. Unless these challenges are addressed, the CRCF risks remaining a layered instrument without real integration into national policy frameworks and with low climate impact.

Agriculture is a major contributor to greenhouse gas (GHG) emissions. Farm-level GHG accounting tools are used to identify mitigation measures and to monitor, report and verify (MRV) GHG profiles and emission reductions. Here we explore opportunities and limitations of farm-level GHG accounting tools based on a global survey covering the practical application of 23 tools used in 30 projects assessing approximately 40'000 farms, and an extensive literature review. We found that most tools are used by experienced scientists in a consultancy context, often associated with a research program. Most tools are of medium complexity and apply "cradle to farm gate" system boundaries. However, we found considerable heterogeneity in scope and methods, particularly for soil carbon fluxes. Furthermore, the necessity to consider consequential system interactions beyond the farm gate is recognized by most users. Results show that due to complexity and numerous methodological uncertainties, the assessment and interpretation of farm-level emission profiles is time-consuming and requires sophisticated tools and great expertise. Decision-making should be based on a set of indicators, thoroughly considering the goal and context of a project. Even then, a fair benchmarking and compensation system is challenging. Accordingly, accounting tools are rarely used for result-based reward mechanisms suggesting that their relevance for compensation mechanisms or emission trading is limited. Their strength lies more in awareness-raising and consultancy for mitigation actions. However, the estimated potentials at farm level of, on average 10-20 % GHG reduction, and the challenges associated with their MRV indicate that a purely technical approach at the farm level is currently insufficient to achieve the necessary GHG reductions. Our results thus point to the need for further capacity development and structural adjustments at a higher level in the agri-food system.

Editorial: Increasing the Ambition of Climate Change Mitigation in Agriculture Whilst Meeting the Sustainable Development Goals (SDGs) and Food Policy Aims