Newest publications
Interannual radial growth response of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) to severe droughts: an analysis along a gradient of soil properties and rooting characteristics
(2024) Spangenberg, Göran; Zimmermann, Reiner; Küppers, Manfred; Schäffer, Jürgen; Hein, Sebastian
Key message: We analyzed stem growth responses of Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) to severe drought in 2003/04 and 2018. The results showed high drought tolerance in sandy, loamy, and most silty soils, with limitations on clayey soils. This study indicates the susceptibility of Douglas-firs with shallow root systems to extreme drought and the importance of deep rooting for high drought resilience.
Context: Although Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) is considered a more drought-tolerant substitute for Norway spruce ( Picea abies (L.) Karst.) in Europe, there is considerable uncertainty about the drought tolerance of Douglas-fir under climate change, specifically concerning soil properties.
Aims: This study aimed to assess the influence of soil texture, plant-available water capacity, and rooting characteristics on the interannual stem growth response of Douglas-fir when exposed to severe drought.
Methods: Along a soil texture gradient from sand to clay, we selected seven closely spaced sites at elevations of approximately 500 m a.s.l. in southern Germany. Mixed-effects models were used to analyze the effects of soil physical and rooting characteristics on growth response indices (resistance, recovery, resilience) related to the severe to extreme droughts in 2003/04 and 2018.
Results: Douglas-fir showed high drought tolerance in sandy, loamy, and most silty soils. However, the results suggest a higher drought stress risk on clayey soils, as well as at specific silty sites with shallow root systems. A higher effective rooting depth increased the resilience of Douglas-fir during the extreme drought in 2018.
Conclusion: Douglas-fir demonstrated its drought tolerance in most soil textures. In addition, this study supports the need for combined above- and below-ground investigations on factors influencing drought tolerance and the importance of rooting for drought resilience.
Semi-natural habitats and their contribution to crop productivity through pollination and pest control: a systematic review
(2025) Alarcon-Segura, V.; Grass, I.; Feuerbacher, A.; Gonzales-Chavez, A.; Mupepele, A. -C.
Context: Semi-natural habitats (SNHs) play a vital role in delivering key ecosystem services, such as crop pollination and biological pest control, which are essential to support agricultural productivity. However, the evidence of the economic benefits of SNHs is scattered, and their impacts on productivity in agricultural landscapes are not well understood, limiting their adoption and integration into farming practices and agricultural policies.
Objectives: In this study, we qualitatively assess the benefits of SNHs for pollination and biological pest control, as well as their translation into economic outcomes. Our objective is to determine whether the spatial scale of the study and the type of metrics used influence the relationship between SNHs and productivity.
Methods: We conducted a systematic review and identified 68 peer-reviewed studies from which we extracted 355 relationships that evaluated the effects of SNHs on productivity. For each relationship, we identified the spatial scale (local or landscape) and the metrics used to measure productivity, pollination or pest control. We conducted a qualitative analysis of the relationships and categorized them as positive, negative, or no evidence for a relationship based on the results reported in the primary studies.
Results: We found that SNHs typically enhance pollination and pest control, with 70% of studies reporting a benefit for diversity of pollinators, flower visitation rates and pest predation. However, the link between SNHs and ecosystem services did not consistently translate into increased productivity. Increase in pollination supply translated into higher productivity when indirect metrics (e.g., flower visitation rate) were measured. In contrast, pest control benefits were largely confined to reductions in pest pressure, with limited evidence of increases in productivity. Importantly, the economic benefits and costs of reallocating land for SNHs remain underexplored, with only 15% of relationships addressing these aspects.
Conclusions: Understanding ecosystem service provision and productivity is challenged by the variability in measures used, mismatches in scale across studies that limit the comparability, and a limited availability of economic data. Advancing this field will require the development of standardized measures that effectively connect biodiversity enhancements with economic outcomes, facilitating quantitative analysis to improve policymaking and the integration of SNHs into sustainable agricultural practices.
Pattern labelling of business communication data
(2022) Kaya, Muhammed-Fatih
Systematic pattern recognition as well as the corresponding description of determined patterns entail numerous challenges in the application context of high-dimensional communication data. These can cause increased effort, especially with regard to machine-based processing concerning the determination of regularities in underlying datasets. Due to the increased expansion of dimensions in multidimensional data spaces, determined patterns are no longer interpretable by humans. Taking these challenges into account, this paper investigates to what extent pre-defined communication patterns can be interpreted for the application area of high-dimensional business communication data. An analytical perspective is considered by taking into account a holistic research approach and by subsequently applying selected Machine Learning methods from Association Rule Discovery, Topic Modelling and Decision Trees with regard to the overall goal of semi-automated pattern labelling. The results show that meaningful descriptions can be derived for the interpretation of pre-defined patterns.
Investigation of the effects of T-2 toxin in chicken-derived three-dimensional hepatic cell cultures
(2024) Vörösházi, Júlia; Mackei, Máté; Sebők, Csilla; Tráj, Patrik; Márton, Rege Anna; Horváth, Dávid Géza; Huber, Korinna; Neogrády, Zsuzsanna; Mátis, Gábor
Despite being one of the most common contaminants of poultry feed, the molecular effects of T-2 toxin on the liver of the exposed animals are still not fully elucidated. To gain more accurate understanding, the effects of T-2 toxin were investigated in the present study in chicken-derived three-dimensional (3D) primary hepatic cell cultures. 3D spheroids were treated with three concentrations (100, 500, 1000 nM) of T-2 toxin for 24 h. Cellular metabolic activity declined in all treated groups as reflected by the Cell Counting Kit-8 assay, while extracellular lactate dehydrogenase activity was increased after 500 nM T-2 toxin exposure. The levels of oxidative stress markers malondialdehyde and protein carbonyl were reduced by the toxin, suggesting effective antioxidant compensatory mechanisms of the liver. Concerning the pro-inflammatory cytokines, IL-6 concentration was decreased, while IL-8 concentration was increased by 100 nM T-2 toxin exposure, indicating the multifaceted immunomodulatory action of the toxin. Further, the metabolic profile of hepatic spheroids was also modulated, confirming the altered lipid and amino acid metabolism of toxin-exposed liver cells. Based on these results, T-2 toxin affected cell viability, hepatocellular metabolism and inflammatory response, likely carried out its toxic effects by affecting the oxidative homeostasis of the cells.
Genome of the early spider-orchid Ophrys sphegodes provides insights into sexual deception and pollinator adaptation
(2024) Russo, Alessia; Alessandrini, Mattia; El Baidouri, Moaine; Frei, Daniel; Galise, Teresa Rosa; Gaidusch, Lara; Oertel, Hannah F.; Garcia Morales, Sara E.; Potente, Giacomo; Tian, Qin; Smetanin, Dmitry; Bertrand, Joris A. M.; Onstein, Renske E.; Panaud, Olivier; Frey, Jürg E.; Cozzolino, Salvatore; Wicker, Thomas; Xu, Shuqing; Grossniklaus, Ueli; Schlüter, Philipp M.
Pollinator-driven evolution of floral traits is thought to be a major driver of angiosperm speciation and diversification. Ophrys orchids mimic female insects to lure male pollinators into pseudocopulation. This strategy, called sexual deception, is species-specific, thereby providing strong premating reproductive isolation. Identifying the genomic architecture underlying pollinator adaptation and speciation may shed light on the mechanisms of angiosperm diversification. Here, we report the 5.2 Gb chromosome-scale genome sequence of Ophrys sphegodes . We find evidence for transposable element expansion that preceded the radiation of the O. sphegodes group, and for gene duplication having contributed to the evolution of chemical mimicry. We report a highly differentiated genomic candidate region for pollinator-mediated evolution on chromosome 2. The Ophrys genome will prove useful for investigations into the repeated evolution of sexual deception, pollinator adaptation and the genomic architectures that facilitate evolutionary radiations.