Publikationsfonds der Universität Hohenheim

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A computer vision approach for quantifying leaf shape of maize (Zea mays L.) and simulating its impact on light interception
(2025) Otto, Dina; Munz, Sebastian; Memic, Emir; Hartung, Jens; Graeff-Hönninger, Simone
The precise determination of leaf shape is crucial for the quantification of morphological variations between individual leaf ranks and cultivars and simulating their impact on light interception in functional-structural plant models (FSPMs). Standard manual measurements on destructively collected leaves are time-intensive and prone to errors, particularly in maize ( Zea mays L.), which has large, undulating leaves that are difficult to flatten. To overcome these limitations, this study presents a new camera method developed as an image-based computer vision approach method for maize leaf shape analysis. A field experiment was conducted with seven commonly used silage maize cultivars at the experimental station Heidfeldhof, University of Hohenheim, Germany, in 2022. To determine the dimensions of fully developed leaves per rank and cultivar, three destructive measurements were conducted until flowering. The new camera method employs a GoPro Hero8 Black camera, integrated within an LI-3100C Area Meter, to capture high-resolution videos (1920 × 1080 pixels, 60 fps). A semi-automated software facilitates object detection, contour extraction, and leaf width determination, including calibration for accuracy. Validation was performed using pixel-counting and contrast analysis, comparing results against standard manual measurements to assess accuracy and reliability. Leaf width functions were fitted to quantify leaf shape parameters. Statistical analysis comparing cultivars and leaf ranks identified significant differences in leaf shape parameters (p < 0.01) for term alpha and term a . Simulations within a FSPM demonstrated that variations in leaf shape can alter light interception by up to 7%, emphasizing the need for precise parameterization in crop growth models. The new camera method provides a basis for future studies investigating rank-dependent leaf shape effects, which can offer an accurate representation of the canopy in FSPMs and improve agricultural decision-making.
A sensitive bioassay to measure NOD1/2 ligands in human serum reveals differential postprandial NOD2 activation
(2025) Biber, Lucy; Schart, Nadine; Bosy-Westphal, Anja; Kufer, Thomas A.
Food intake is associated with the occurrence of components and metabolites from the gut microbiota in the bloodstream. Using a widely utilised cell-based assay to measure bacterial peptidoglycan via pattern-recognition receptor activation, we found that the performance of this assay is significantly influenced by the presence of other serum components. To address this challenge, an alternative luciferase-based reporter assay protocol was established to accurately measure NOD1 and NOD2 activation by serum samples with high sensitivity. Utilising postprandial human serum samples, we tested this assay and showed that the concentration of NOD2-activating ligands differed in the postprandial phase. Together, we provide a protocol to measure NOD1/2 activation by human serum samples and highlight a role for NOD2 in the postprandial response.
Adapting wheat production to global warming in West Asia: facultative wheat outperforms winter and spring wheat at conventional nitrogen levels
(2025) Yousefi, Afsaneh; Koocheki, Alireza; Mahallati, Mehdi Nassiri; Khorramdel, Soroor; Trenz, Jonas; Malakshahi Kurdestani, Ali; Ludewig, Uwe; Maywald, Niels Julian
Global warming and weather anomalies pose significant threats to cereal production in West Asia. Winter wheat, which requires vernalization to trigger reproductive growth, is particularly vulnerable to heat, while spring wheat faces limitations due to short and hot vegetation periods. Facultative wheat, which does not require vernalization and can be planted in either fall or spring, offers potential flexibility and resilience to fluctuating temperatures. This study aimed to evaluate the development and grain yield of facultative, spring, and winter wheat varieties under different nitrogen fertilization rates in current climate conditions. Facultative wheat, grown as either facultative winter (FWW) or facultative spring (FSW), along with winter (WW) and spring wheat (SW) varieties, was cultivated over two consecutive seasons (2020–2022) at Ferdowsi University of Mashhad, Iran. Developmental stages were monitored, and grain yield, protein, and nutrient concentrations were measured at four nitrogen levels (0, 100, 200, and 300 kg N ha −1 ) in both shoots and grains. Crop modeling under the RCP 8.5 climate scenario supported the experiments and projections. Facultative wheat sown in autumn exhibited a shorter tillering stage and a longer early reproductive stage compared to winter wheat. While nitrogen fertilization delayed development, it significantly increased yield. Facultative wheat achieved higher grain yields at conventional nitrogen levels (100–200 kg N ha −1 ). Additionally, increasing nitrogen fertilization improved grain protein and nutrient concentrations (N, P, and K). Crop modeling indicated that facultative varieties sown in winter could offer greater yield stability and might benefit from a more consistent phenological development. Overall, facultative wheat performed better at conventional nitrogen levels, highlighting its potential in a changing climate in West Asia. Optimizing sowing dates and nitrogen fertilization could help mitigate some of the negative effects of rising temperatures, enhancing wheat resilience and productivity.
The adoption potential of extended lactation as a strategy to reduce excess calf numbers in dairy farming
(2024) Gresham, Josephine; Reiber, Christoph; Chagunda, Mizeck G. G.
Dairy production relies predominantly on a few, selectively bred, high-yielding dairy breeds, resulting in a surplus of low-value male offspring. This situation leads to a conflict between a growing demand for milk and low appreciation for dairy calves. Extending lactation could reduce the number of calves born. This study aimed to assess the current use of extended lactation in dairy production in Southern Germany, identify the perceived potential, and determine the biological potential extended lactation has to reduce calf numbers. A survey from 2020 with 310 farmers was analysed. A total of 145 (46.8%) farmers used extended lactation. The use of extended lactation on farms correlated significantly with breed, milk yield, interest in continuing or implementing the use of extended lactation, and the indicated feasibility of extended lactation. The perceived potential was assessed by 39.8% of farmers as “high” to “very high”. A total of 17 (12.8%) farmers currently not using extended lactation were identified as potential adopters. Together with existing adopters, this could result in 52.3% of farms using extended lactation, which could biologically reduce calf numbers by 7.3% or 14.1% p.a., when extended by three or six months, respectively. This adoption potential shows that extended lactation can reduce calf numbers considerably, addressing both ethical and economic concerns in dairy farming and benefiting farmers as well as society.
The affective, cognitive, and behavioral echo of cumulative series reception aka binge-watching: A qualitative study
(2025) Eberhard-Bölz, Sarah
When analyzing the cumulative reception of TV series, often called binge-watching (i.e., watching several episodes of one TV series back-to-back), there has been a strong focus on potentially harmful consequences in the literature, such as insomnia, anxiety, depression symptoms, and particularly addiction. However, only a few extant studies have considered potential nonharmful or even beneficial consequences from binge-watching. The present study addresses this gap in the binge-watching literature and calls for future studies that address the gap between the two contrasting perspectives on binge-watching, i.e., whether it is a harmful or beneficial behavior. In the present study, 24 semi-structured, diary-based interviews were conducted with young adults, yielding a wide spectrum of thoughts, affects, and behaviors that outlasted the exposure situation. The qualitative content analysis revealed long-term effects, such as transferred positive and negative moods, delayed sleep, feelings of inspiration or motivation, and urges to research or communicate about the TV series. A key finding was that binge-watching also triggered affective states such as heightened arousal or grieving, which could last up to several hours or days. The described media effects' potential persistence demonstrates the importance of considering the time aspect in future research because the longer the effects last, the longer they potentially impact one's everyday live.
AI-assisted tractor control for secondary tillage
(2025) Boysen, Jonas; Bökle, Sebastian; Stein, Anthony
Modern agricultural machinery requires skilled operators to optimally configure their complex machines, while autonomous machines without operators must already optimize their configuration themselves to achieve optimal performance. During secondary tillage multiple performance measures need to be monitored and maximized: Seedbed quality, area output and fuel consumption. The seedbed quality can be measured with the soil surface roughness coefficient which can be computed with 3D-cameras attached to the machine. For our work, such cameras are mounted in the front and back of a Claas Arion 660 tractor with an attached power harrow seeding combination. The soil-machine response model of our prior work is utilized to model the soil-machine interaction for the training of a reinforcement learning agent and the application of a decision-time planning agent to assist in controlling the working speed of the machine. The control agents are tested in real-world field trials and compared to good professional practice. The decision-time planning agent achieves comparable results to a gold-standard while reaching significantly higher performance in terms of area output (29.1%) and more efficient fuel consumption (8.4%) than a baseline while the reinforcement learning agent performed worse during the field trials. The seedbed quality and field emergence are not showing significant differences between the variants. Further analysis shows that model training and selection for the reinforcement agent could have led to performance loss and models that are performing better in simulation have been trained after the field trials. Furthermore, we analyze the models when tested under the field conditions in the field trials (out-of-distribution) that are different from the field conditions during training data collection. The out-of-distribution testing leads to a reduced performance in terms of rRMSE of the decision-time planning agent and to some extend reward of the reinforcement learning agent compared to in-distribution testing.
Animal welfare in non-anthropocentric cost-benefit analysis and social welfare functions: a critical review to guide practical application
(2025) Dusel, Sara; Wieck, Christine
Cost-benefit analysis and social welfare functions are two closely related methods to evaluate policy impacts. In this critical review, we present the state of knowledge on how to include the animals’ (non-anthropocentric) perspective in these policy evaluations. For this, we synthesize material from the scientific and grey literature and develop a checklist that guides through the process of non-anthropocentric cost-benefit analysis and social welfare functions. Step-by-step, the checklist gives an overview of the alternative options and normative assumptions in the literature and points to remaining research gaps.
Antiviral defense systems in the rumen microbiome
(2025) Sáenz, Johan S.; Rios-Galicia, Bibiana; Seifert, Jana
The continuous interaction between phages and their respective hosts has resulted in the evolution of multiple bacterial immune mechanisms. However, the diversity and prevalence of antiviral defense systems in complex communities are still unknown. We therefore investigated the diversity and abundance of viral defense systems in 3,038 high-quality bacterial and archaeal genomes from the rumen. In total, 14,241 defense systems and 31,948 antiviral-related genes were identified. Those genes represented 114 unique system types grouped into 49 families. We observed a high prevalence of defense systems in the genomes. However, the number of defense systems, defense system families, and system density varied widely from genome to genome. Additionally, the number of defense system per genome correlated positively with the number of defense system families and the genome size. Restriction modification, Abi, and cas system families were the most common, but many rare systems were present in only 1% of the genomes. Antiviral defense systems are prevalent and diverse in the rumen, but only a few are dominant, indicating that most systems are rarely present. However, the collection of systems throughout the rumen may represent a pool of mechanisms that can be shared by different members of the community and modulate the phage–host interaction.
Associations and patterns in lifestyle and body weight among university students over one year into the Covid-19 pandemic: A cluster analysis
(2025) Bschaden, Andreas; Ströbele-Benschop, Nanette
In March 2020, the first wave of SARS-CoV-2 infections led to far-reaching measures worldwide to slow the spread of the virus. University students were particularly affected by the COVID-19 pandemic due to the shift to distance learning. Research found an increase in body weight among a significant proportion of students, as well as unfavourable changes in food consumption and physical activity in the first months of the pandemic. The present study aimed to examine changes in food consumption, physical activity, and body weight more than one year into the COVID-19 pandemic. A cross-sectional online survey was conducted among students at a German university in July/August 2021 (n = 951). Changes in food consumption, physical activity, and self-reported body weight since the beginning of the pandemic were assessed in comparison to pre-pandemic levels. Weight gain was reported by 38 % of students, weight loss by 30 %. Changes in sweet and savoury snacks consumption were positively, and changes in sporting frequency and fruit consumption were negatively associated with weight change. A cluster analysis revealed five groups of student clusters, two of which were able to benefit from the changes in their daily lives with increased physical activity and vegetable consumption. Negative consequences, such as reduced physical activity or increased sweet and savoury snack consumption, were found in two groups. One group appeared to be unaffected. The study helps to understand how the pandemic affected students differently. A closer look is needed to identify the reasons for these varied consequences and to develop strategies to assist those who are struggling to better cope with such situations.
Bioaccessibility and anti-inflammatory activity in Caco-2 cells of phytochemicals from industrial by-products of coffee (Coffea arabica L.)
(2025) Jiménez-Gutiérrez, Milena; Zielinski, Christian; Esquivel, Patricia; Frank, Jan; Irías-Mata, Andrea; Jiménez-Aspee, Felipe
Coffee by-products are rich in nutrients and bioactive compounds in free soluble form and bound to cell wall components. These compounds undergo chemical changes during gastrointestinal digestion, affecting their bioaccessibility and bioactivity. This study is the first to investigate coffee by-products from industrial wet processing to evaluate the impact of simulated gastrointestinal digestion on their phytochemical composition and subsequent anti-inflammatory activity in Caco-2 cells. Digestion significantly reduced the stability and solubility of main compounds; however, digested bioaccessible by-products still exhibited anti-inflammatory properties, reducing IL-6, IL-8, and TNF-α levels. Correlation analysis identified rutin, quercetin-3-glycoside, caffeine and 5-caffeoylquinic acid as strongly linked to cytokine suppression, suggesting key roles and possible synergies. These results highlight the potential of coffee by-products as functional ingredients targeting intestinal inflammation. Future work should confirm in vivo efficacy, optimize extraction at scale, and address regulatory requirements to support industrial application and promote circular economy benefits.
Bioprocess exploitation of microaerobic auto-induction using the example of rhamnolipid biosynthesis in Pseudomonas putida KT2440
(2025) Grether, Jakob; Dittmann, Holger; Willems, Leon; Schmiegelt, Tabea; Benatto Perino, Elvio Henrique; Hubel, Philipp; Lilge, Lars; Hausmann, Rudolf
Background: In biomanufacturing of surface-active agents, such as rhamnolipids, excessive foaming is a significant obstacle for the development of high-performing bioprocesses. The exploitation of the inherent tolerance of Pseudomonas putida KT2440, an obligate aerobic bacterium, to microaerobic conditions has received little attention so far. Here low-oxygen inducible promoters were characterized in biosensor strains and exploited for process control under reduction of foam formation by low aeration and stirring rates during biosynthesis of rhamnolipids. Results: In this study, homologous promoters of P. putida inducible under oxygen limitation were identified by non-targeted proteomic analyses and characterized by fluorometric methods. Proteomics indicated a remodeling of the respiratory chain and the regulation of stress-related proteins under oxygen limitation. Of the three promoters tested in fluorescent biosensor assays, the promoter of the oxygen-sensitive cbb3-type cytochrome c oxidase gene showed high oxygen-dependent controllability. It was used to control the gene expression of a heterologous di-rhamnolipid synthesis operon in an auto-inducing microaerobic two-phase bioprocess. By limiting the oxygen supply via low aeration and stirring rates, the bioprocess was clearly divided into a growth and a production phase, and sources of foam formation were reduced. Accordingly, rhamnolipid synthesis did not have to be controlled externally, as the oxygen-sensitive promoter was autonomously activated as soon as the oxygen level reached microaerobic conditions. A critical threshold of about 20% oxygen saturation was determined. Conclusions: Utilizing the inherent tolerance of P. putida to microaerobic conditions in combination with the application of homologous, low-oxygen inducible promoters is a novel and efficient strategy to control bioprocesses. Fermentation under microaerobic conditions enabled the induction of rhamnolipid production by low oxygen levels, while foam formation was limited by low aeration and stirring rates.
Can market fragmentation explain the limited success of political attempts to promote grain legume cultivation in Germany?
(2025) Mittag, Franziska; Hess, Sebastian
Grain legumes, such as field peas, field beans, sweet lupins and soybeans, are known to increase biodiversity within the appropriate crop rotation and are an important source of import-substituting feed protein. National and regional policy schemes have long tried to support the cultivation of grain legumes. Although many regions in Germany offer favourable conditions for grain legumes, previous subsidy schemes have failed to increase the area under cultivation and farmers report a lack of market incentives. Indeed, the available price data exhibit a substantial share of non-random missing values in weeks when grain legumes were not traded. We analyse these non-price periods using cointegration tests and single-hurdle Tobit models. The results indicate that regional price formation for grain legumes in German regions depends not only on a minimum quantity of the respective legume crop in supply but also on a favourable supra-regional soybean price: Regional grain legume markets are not integrated and show evidence of a fragmented market structure. This may explain why local grain legume value chains have failed to emerge in Germany, despite decades of policy attempts to support these crops.
The chicken gut microbiome in conventional and alternative production systems
(2025) Cheng, Yu-Chieh; Krieger, Margret; Korves, Anna-Maria; Camarinha‑Silva, Amélia
The poultry gut microbiome plays a key role in nutrient digestion, immune function, and overall health. Differences among various farming systems, including conventional, antibiotic-free, free-range, and organic systems, influence microbial composition and function through variations in diet, genetic selection, environmental exposure, and antibiotic use. Conventional systems typically rely on formulated diets and controlled housing conditions, often with routine antimicrobial use. In contrast, organic systems emphasize natural feed ingredients, including roughage, outdoor access, and strict limitations on the use of antibiotics. These divergent practices shape the gut microbiota differently, with organic systems generally associated with greater exposure to environmental microbes and, consequently, greater microbial diversity. However, the implications of this increased diversity for poultry health and performance are complex, as organic systems may also carry a higher risk of pathogen exposure. This review summarizes current findings on the chicken gut microbiome across conventional and alternative production systems (antibiotic-free, free-range, and organic), focusing on microbial diversity, functional potential, and disease resilience. The need for standardized methodologies and consistent nomenclature in microbiome research is also discussed to improve comparability across studies. Understanding how production systems influence the gut microbiota is essential for improving poultry health and productivity while addressing challenges related to antimicrobial resistance and sustainable farming practices.
Chloride application enhances photosynthesis and facilitates nitrate translocation while driving chloride translocation into roots
(2025) Wei, Guanghui; Zhang, Xudong; Franzisky, Bastian L.; Geilfus, Christoph‐Martin; Zörb, Christian
Chloride and nitrate are essential mineral elements for crop growth. Due to their similar physical and electrochemical properties, their uptake and translocation interact antagonistically. This suggests that applying chloride to the leaf canopy during the late grain‐filling stage of cereals might enhance nitrate use efficiency. Hence, it remains uncertain whether foliar‐applied chloride at the late growth stage stimulates nitrate translocation from mature to younger leaves. To explore this possibility, two contrasting faba bean varieties were grown in a climate‐controlled chamber. Nitrate concentrations of approximately 50 and 93 μg mg FW −1 , respectively, were established in leaves by depleting nitrogen in the rooting medium. Based on these two nitrate concentrations in mature leaves, chloride was applied to the leaf canopy. Measurements of biomass, photosynthesis, and nitrate and chloride concentrations in both young and mature leaves revealed that chloride foliar application raised nitrate levels in younger leaves from 7.1 to 9.5 μmol g FW −1 and boosted photosynthesis by approximately 35%. However, one of the two faba bean varieties did not respond significantly to the chloride foliar application. These findings indicate that chloride application facilitates nitrate translocation from mature to younger leaves, potentially improving grain nitrogen supply. As a result, nitrate use efficiency might be increased by chloride application during late growth stages, although this effect is genotype‐dependent.
Classifying early-stage soybean fungal diseases on hyperspectral images using convolutional neural networks
(2025) Hsiao, Chieh Fu; Feyrer, Georg; Stein, Anthony
Using convolutional neural networks (CNNs) to detect plant diseases has proven to reach high accuracy in the classification of infected and non-infected plant images. However, most of the existing researches are based on RGB images due to the availability and the comparably low cost of image collection. The limited spectral information restricts the detectability of plant diseases, especially in the early stage where often symptoms of pathogen infection have not yet become visible. To this end, in this study, hyperspectral imaging (HSI) data are combined with deep learning models to test the classification ability of two soybean fungal diseases: Asian soybean rust (Phakopsora pachyhizi) and soybean stem rust (Sclerotinia scleroriorum). Different CNNs employing 2D, 3D convolution, and hybrid approaches are compared. The influences of the depth of the convolutional layer and the regularization techniques are also discussed. Besides, image augmentation methods are investigated to overcome the problem of data scarcity. The results indicate the 6-convolutional-layer depth hybrid model to have the best capacity in classifying Asian soybean rust in the early-mid to mid-late stage when there are over 2 % visible symptoms but a limited detectability in the early stages when there are below 2 % visible symptoms on leaves. On the other hand, the optimized CNN model shows a limited capability to detect both diseases when there are no visible symptoms observable. Overall, this study suggests a hybrid 2D-3D convolutional model with augmentation and regularization methods has a high potential in the early detection of fungal diseases. This research is expected to contribute to a new cropping system that vastly reduces the chemical-synthesis plant protection products, where a continuous pathogen disease monitoring plays a key to manage the crop stands.
Coffee berry borer control, but not coffee yield, is mediated by non-additive interaction between birds and ants across different cultivation systems
(2026) Cardona Tejada, Damaris A.; Parra, Juan L.; Grass, Ingo; Schurr, Frank M.
Coffee is one of the most traded tropical crops, cultivated in some of the most biodiverse regions on the planet. Coffee production can be seriously reduced by the coffee berry borer (CBB), a specialized beetle that feeds on the endosperm of coffee berries. Given the CBB's economic relevance, coffee-producing countries have developed extensive Integrated Pest Management programs. Nonetheless, most of these programs fail to incorporate CBB control by natural enemies such as birds and ants. While the effects of birds and ants on CBB suppression have been demonstrated to be positive when studied in isolation, their interactive effects have been little studied. To better understand the effects of the trophic interaction between birds and ants on CBB control, we conducted a full-factorial block experiment excluding birds and ants from coffee shrubs. We distributed 49 experimental blocks across three different coffee systems in a Colombian landscape: sun-exposed coffee, coffee-plantain intercropping, and shade coffee. We found birds to be key control agents of CBB: in the presence of ants, bird exclusion increased CBB infestation by 36 %. However, in the absence of ants, birds had little effect on CBB infestation, demonstrating that the effects of birds and ants were non-additive. This suggests that birds control CBB through a trophic cascade mediated by ants. We also found that the effects of exclusions were modified by the cultivation system, with the shade coffee system consistently reducing CBB infestation. Our experiment demonstrates that crop diversification is an effective measure for integrating local enemies into IPM strategies. Nonetheless, we acknowledge that trophic interactions are highly complex and exhibit a context-dependency that can result in the suppression of biological pest control. Therefore, we recommend conducting future analysis on evaluating the effects of predator´s community composition to encourage the development of IPM programs that leverage biodiversity in agroecosystems.
Comparative ungulate diversity and biomass change with human use and drought: implications for community stability and protected area prioritization in African savannas
(2025) Bartzke, Gundula S.; Ogutu, Joseph O.; Piepho, Hans‐Peter; Bedelian, Claire; Rainy, Michael E.; Kruska, Russel L.; Worden, Jeffrey S.; Kimani, Kamau; McCartney, Michael J.; Ng'ang'a, Leah; Kinoti, Jeniffer; Njuguna, Evanson C.; Wilson, Cathleen J.; Lamprey, Richard; Hobbs, Nicholas Thompson; Reid, Robin S.
Drought and human use may alter ungulate diversity and biomass in contrasting ways. In African savannas, resource‐dependent grazers such as wildebeest (Connochaetes taurinus) and zebra (Equus quagga) may decline or disperse as resources decline, opening space for more drought‐tolerant species such as gazelles (Eudorcas and Nanger) and impala (Aepyceros melampus). This shift can increase species richness, evenness, and overall ungulate diversity. Although higher diversity may stabilize ungulate communities, it may be associated with lower biomass (the total body mass of all individuals in a community), which in turn affects vegetation structure and composition, nutrient cycling, energy flows, and other organisms in savannas. While ungulate biomass often declines during drought or in areas of intense human use, the effects on diversity changes under low‐to‐moderate human use remain less clear. Our fine‐scale censuses in the Maasai Mara National Reserve and adjacent pastoral lands in Kenya showed that ungulate biomass declined more than diversity in the 1999 drought year. In the normal rainfall year of 2002, diversity peaked along the reserve boundary, but species richness leveled off in the drought year. Biomass peaked in the reserve in both census years, and migratory ungulates moved further into the reserve in the drought year, where diversity declined. These findings suggest that core protected areas are crucial for maintaining ungulate biomass, while transition zones from protected and pastoral lands support higher diversity unless drought reduces species richness.
Comparing hops and malt price transmission in the beer value chain: evidence from Germany
(2025) Hess, Sebastian; Bublik, Nikolas
The German beer value chain has received limited attention so far, despite the country’s central role in global beer production. This study investigates the price dynamics of its two key inputs—hops and malt—using monthly price data from 2015 to 2024 based on a unique dataset from a German hops cooperative. While contract farming is common for both raw materials, malt is traded via private firms, whereas hops are marketed almost exclusively through farmer-owned cooperatives. A vector error correction model (VECM) is estimated, incorporating structural break dummies identified through Bai–Perron tests, followed by forecast error variance decomposition (FEVD) and impulse response function (IRF) analysis. The results show that hop prices are largely self-driven and adjust more quickly to deviations from equilibrium than malt or beer prices. While malt and beer exhibit stronger interdependencies, the hop sector displays greater price stability. The findings further reveal that the malting sector responded significantly to the recent energy price crisis in Germany, whereas the hop sector did not.
A concept of a decentral server infrastructure to connect farms, secure data, and increase the resilience of digital farming
(2025) Bökle, Sebastian; Gscheidle, Michael; Weis, Martin; Paraforos, Dimitrios S.; Griepentrog, Hans W.
With the intensified use and integration of digital technologies in agriculture, dependencies and constraints occurred which weakened the adoption and reduced effectiveness of innovative technology due to lacking interoperability and resilience. As awareness of these problems increased concepts have been developed to meet this issue with decentralized IT- infrastructures. With the proposed concept the authors aim to refine these existing infrastructures with concrete suggestions for server infrastructures. Off-the-shelf hardware and open-source software, enable cheap access to digital technologies yet provide sufficient support by choosing open-source tools with big or active communities. With the involvement of the machinery rings the economic advantages scale up because of the interfarm use of expensive technology. The farmservers on the farmside are the edge nodes of a regional network. The local machinery ring is the next node which is supposed to offer remote services for the farmers, who have a trustful partner in the machinery rings. The concept orients on revised requirements enriched by the results of a survey, conducted by the authors, adding the focus on interfarm cooperations. The concept meets the main constraints farmers face in digitalization: Data sovereignty, resilience, interoperability, high costs, and trust.
Connecting resonance theory with social-ecological thinking: Conceptualizing self-world relationships in the context of sustainability transformations
(2025) Brossette, Florian; Bieling, Claudia
Relationships and interactions between humans and their environment play an important role in sustainability transformations. However, their conceptualization remains a big challenge in current social-ecological research. We propose resonance theory by the German sociologist Hartmut Rosa as a fruitful framework to advance social-ecological thinking. Resonance theory investigates the quality of the relationships between self and world and scrutinizes their relevance for transformations. To illustrate the potentials of resonance theory, we use a vignette approach to cases of landscape stewardship initiatives in the Black Forest Biosphere Reserve in Germany. In distinguishing between self and world and highlighting the role of relationships, resonance theory brings ontological and epistemological clarity, while overcoming a strict dichotomy between social and ecological. We find that resonance theory provides a much needed framework to describe how system-wide transformations emerge from interactions and out of relationships at the individual level. We argue that resonance theory contributes to social-ecological systems thinking by adding the notion of uncontrollability in transformations and shifting the debate on agency towards relationships. Synthesis and applications: This paper demonstrates the meaningfulness of relational paradigms for real-world transformations in theory and practice.

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