Christian Sponagel

European wine growers face major market and consequently economic challenges. Currently, the European Union undertakes efforts to stabilize the market by financial support to reduce wine or wine growing capacity. Policiy interventions aiming at vineyard reduction in light of preserving cultural landscapes are subject of intense debate. However, there is a lack of evidence-based decision-making frameworks. Therefore, we are using a discrete choice experiment to investigate the conditions under which wine-growing farmers in Germany would participate in governmentfunded grubbing up programs, i. e. the clearing of land accompanied by the permanent or temporary withdrawal from winegrowing. Our results show that preferences are highly heterogeneous and depend not only on the magnitude of financial compensation, but also on the farms' structural conditions. For instance, part-time farms, farms that cultivate other agricultural crops besides wine and farms with land in protected areas could be prioritised, as they expressed a significantly higher willingness to participate in the relevant schemes. Specifically, they expect lower financial compensation. Extrapolating the sampled population results shows that introducing a grubbing up premium of 2,500 €/ha/year, with farms claiming subsidies for 1-3 hectares each, could amount to 30 € million per year in Rhineland-Palatinate alone. The design of policy schemes is a key for the instrument's efficiency and governmental expenditures. For example, a targeted approach for vineyards in environmental protected areas will reduce capacity but with limited financial resources. The analyses provide relevant information for winegrowing policies in Germany but also for other European countries and regions, inviting to replicate the framework for other country-specific or other crop studies. It also highlights the broader implications of grubbing up schemes for the future utilisation of agricultural land and the development of rural landscapes in regions that are largely shaped by wine production today.

Agricultural droughts in many humid regions such as Southern Germany are projected to become more frequent and severe, leading to a substantial rise in irrigation demand to secure crop production. As a result, irrigation is becoming an increasingly important factor in agricultural production, and operational and regulatory decision-makers are relying more on data on site-specific yield responses to severe drought, especially as spatial soil heterogeneity leads to pronounced yield variability. Statistical crop yield models are commonly used to predict yield responses to drought; however, their calibration is often based on aggregated yield data, which can bias predictions of site-specific yield responses. Reported aggregated yield data for drought years are difficult to interpret because it is unclear whether crops were irrigated and to what extent. The aim of this study is to introduce a methodological approach to forecast agro-economic impacts of increasing drought frequency, using site-specific soil properties, meteorological data and yield observations from past drought years to assess potential impacts of future consecutive drought events. High drought frequencies are represented by repeatedly applying the severe drought conditions of 2003 over time. The process-based hydrological model RoGeR was coupled with a linear mixed-effects model, combining simulated soil moisture data with spatially corresponding observed yield data from post-registration variety trials (Landessortenversuche) in the German state of Baden-Württemberg. Yield data from the variety trials are characterized by standardized management practices, particularly with respect to irrigation. We demonstrate the proposed approach in a case study in Southern Germany by forecasting yields under rainfed and irrigation scenarios as well as irrigation volumes for major arable crops and representative soils for the period 2000–2024. The results showed that both yield losses and irrigation-induced yield gains during drought vary significantly between crops and across sites and are associated with substantial differences in irrigation volumes and the number of irrigation events, which in turn affect the profitability of irrigation investments. The findings confirm that site-specific modelling of yield effects is essential for evaluating the profitability of irrigation investments. Our approach provides the necessary data basis and can be applied across spatial scales.

Drained peatlands account for around four per cent of global anthropogenic greenhouse gas (GHG) emissions. The EU is the second largest emitter worldwide, with Germany having the highest emissions within the EU. Protecting peatlands in the EU, and in Germany in particular, is therefore a key priority in terms of climate policy. In Germany, agriculture is the dominant land use in terms of drained peatlands, and rewetting them can therefore pose particular challenges and be associated with substantial economic impacts on farms in highly productive regions. We have therefore focused on the GHG reduction potential and farm economic impacts of a large-scale rewetting of agricultural peatlands in Upper Swabia (districts of Biberach, Bodenseekreis, Ravensburg and Sigmaringen), a region in Baden-Württemberg characterized by intensive dairy farming on the border with Bavaria and Austria. A key feature of the analysis was the highly spatially resolved integrated economic and hydrological modelling approach, which we believe to be unique in the southern German context. This enabled us to consider the interplay between local factors such as the spatial configuration and location of peatlands, site-specific hydrological conditions, and plot-specific land use on a regional scale. Methodologically the geodata-based economic model PALUD was coupled with the hydrological model RoGeR. Based on site-specific groundwater levels modeled with RoGeR in a scenario with drainage (reference) and without drainage to raise the groundwater level (peatland rewetting scenario), the achievable GHG reduction through rewetting was calculated and transferred to PALUD. Depending on a model-derived payment for each avoided t CO2eq on the peatland areas, the results showed that with payments between 100 and 200 € per t CO2eq, between approximately 50% and nearly 100% of the maximum GHG reduction potential of approx. 282,333 t CO2eq a-1 on the peatland areas could be realized. While the economic impact at sector level was relatively low, the model results showed considerable effects on individual farms under the assumptions made. For instance, approximately 9% of farms with land on organic soils lost over 30% of their gross margin when around 50% of the considered peatland area was rewetted. The economic effects on individual farms depended highly on the proportion of land on peatlands. Moderate GHG abatement costs can thus lead to substantial income losses for individual farms and pose a significant obstacle to large-scale peatland rewetting. A forward-looking strategic land management could be essential, such as creating land pools to reserve exchange land for affected farms. Further research is also needed on economically viable land-use concepts for rewetted peatlands, as well as on their socioeconomic impacts. Our analyses provide a solid foundation for decision-making in agricultural and environmental policy in Baden-Württemberg, as well as in other regions with intensive dairy farming and peatlands.

The Common Agricultural Policy (CAP) has increasingly integrated environmental and climate protection into its objectives, which may indirectly support cultural ecosystem services (CES) and human health. However, the role of CES has received little attention in studies examining impacts of the CAP. Using the Stuttgart Region in Germany, representative of many comparable polycentric metropolitan regions on Europe with a high demand for CES, this study provides an ex-post assessment of how CAP measures contribute to CES, such as landscape aesthetics and recreation. Changes in the spatial distribution of CAP measures recorded by the Integrated Administration and Control System (IACS) data in the years 2020 to 2024 are analysed, allowing comparison between the previous CAP funding period (before 2023) and the current one (from 2023 onwards). The analysis focuses on measures with recreational and aesthetic potential due to their spatial configuration, structural characteristics and visually appealing flowering aspects. Results reveal increasing concentrations of measures on agricultural land at greater distances from settlements, except for fallow land. Flower strips, fallow land, and structural elements are generally located in areas with a low aesthetic and recreational value. The new CAP funding period shows increased shares of extensive grassland and fallow land and decreased shares of structural elements and flower strips in the dataset investigated. Overall, results suggest limited temporal progress in the spatial allocation of biodiversity promoting agricultural measures from an aesthetic and recreational perspective. The findings highlight the need for targeted policy action in areas of high CES-demand.

Conserving biodiversity, especially in agricultural landscapes, is a major societal challenge. Broad scientific evidence exists on the impacts of single drivers on biodiversity, such as the intensification of agriculture. However, halting biodiversity decline requires a systemic understanding of the interactions between multiple drivers, which has hardly been achieved so far. Selecting Germany as a case study, the goal of our analysis is (i) to understand how various socio‐economic drivers of biodiversity in agricultural landscapes interact at the national scale, (ii) to identify plausible pathways that most likely will lead to an improvement of biodiversity in agricultural landscapes and (iii) to discuss guiding principles for policy‐making based on the pathways. We applied the expert‐based Cross‐Impact‐Balance (CIB) methodology to the German agri‐food system (target year 2030). Seven descriptors that represent the most relevant socio‐economic drivers of biodiversity (here, we focus on species richness) in agricultural landscapes in Germany were defined. In three workshops with different groups of experts, we assessed all the interactions and impacts between these descriptors. From the workshops, seven overlapping scenarios were identified and aggregated into four main future pathways for enhancing biodiversity in agricultural landscapes. These pathways are: (1) ‘Innovation and stricter legislation’, (2) ‘Major change in protein production and CAP shift’, (3) ‘Major change in protein production and national legislation’ and (4) ‘Major social changes compensate for a lack of innovation in food production’. Socio‐economic drivers interact to varying degrees. Societal values have a strong active influence on the system, e. g. agricultural policy, whereas the orientation and objectives of agriculture, e. g. focus on public goods, are rather passively determined. Conserving biodiversity thus depends upon the evolution of societal values, European and national nature conservation and agricultural policies, innovations in plant and protein production as well as on global commodity markets. A key message for policymakers is that there are generally different, complementary options for achieving the objective of improving biodiversity. This is important when specific drivers such as the CAP cannot be steered in a particular desired direction. Read the free Plain Language Summary for this article on the Journal blog.