Newest publications
DIY Insektenscheuche 2.0
Konzept und Umsetzung im Projekt InsectMow
(2025) Frank, Jonas
Kurzanleitung zum Bau der Insektenscheuche aus dem Projekt InsectMow. Zweite, aktualisierte und ergänzte Version
Technical evaluation of a solar-biomass flatbed dryer for maize cobs drying in Rwanda
(2023) Ntwali, Janvier; Romuli, Sebastian; Bonzi, Joévin Wiomou; Müller, Joachim
The persistent problem of postharvest losses in the maize value chain poses an arduous challenge for smallholder farmers in Rwanda, ultimately reducing their market bargaining power. As a consequence, there is an exacerbated disparity in revenues that makes farmers, predominantly female farmers, more vulnerable. The existing drying facilities are based on ambient air drying with a long drying time and the alternative mechanical dryers use mostly fossil fuels which is not a sustainable solution. A solar-biomass hybrid flatbed dryer for maize cobs drying was designed and constructed in the high-altitude volcanic zone of Rwanda. The objective was to provide farmers with an affordable and sustainable drying system with a high drying rate compared to the existing method. In this study, we present the results of the technical evaluation of the dryer to rate its capacity to dry maize cobs to the recommended moisture content. Energy balance was assessed by temperature sensors, airflow distribution was measured with a vane anemometer and the solar radiation from weather station were compared to the solar system data recorded through a datalogging charge controller. Maize was dried in three batches and the moisture content was measure with oven method. Results showed a uniform distribution of airflow on the dryer perforated flow. The burner consumed on average 6 kg of empty cobs per hour and the burner efficiency was 59.4 %. The solar system provided a maximum daily yield of 2.6 kWh, and the battery was able to maintain the system during days of low solar energy availability. Maize cobs were dried from an average moisture content of 23.0 % to 13.7 % in an average period of 90.6 hours. This drying time was significantly lower compared to the already existing system which uses more than 6 weeks. The results prove that the solar-Biomass hybrid flatbed dryer was appropriate for drying maize cobs to the recommended moisture content and thus reduce the risk of postharvest losses in maize value chain in Rwanda. The dryer might be further improved by combining the burner with a solar heating system to further reduce the biomass mass consumption.
Testing agronomic treatments to improve the establishment of novel miscanthus hybrids on marginal land
(2025) Lewin, Eva; Clifton-Brown, John; Jensen, Elaine; Lewandowski, Iris; Krzyżak, Jacek; Pogrzeba, Marta; Hartung, Jens; Wolfmüller, Cedric; Kiesel, Andreas; Lewin, Eva; Department Biobased Resources in the Bioeconomy, University of Hohenheim, 70599 Stuttgart, Germany; Clifton-Brown, John; Department of Agronomy and Plant Breeding, Justus Libeig University Giessen, 35392 Giessen, Germany; Jensen, Elaine; Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth SY23 3EE, UK; Lewandowski, Iris; Department Biobased Resources in the Bioeconomy, University of Hohenheim, 70599 Stuttgart, Germany; Krzyżak, Jacek; Institute for Ecology of Industrial Areas, 40-844 Katowice, Poland; Pogrzeba, Marta; Institute for Ecology of Industrial Areas, 40-844 Katowice, Poland; Hartung, Jens; Sustainable Agriculture and Energy Systems Department, University of Applied Science Weihenstephan-Triesdorf, 91746 Freising, Germany; Wolfmüller, Cedric; Department Biobased Resources in the Bioeconomy, University of Hohenheim, 70599 Stuttgart, Germany; Kiesel, Andreas; Department Biobased Resources in the Bioeconomy, University of Hohenheim, 70599 Stuttgart, Germany; Fujii, Yoshiharu
Miscanthus is considered a promising candidate for the cultivation of marginal land. This land poses unique challenges, and experiments have shown that the “establishment phase” is of paramount importance to the long-term yield performance of miscanthus. This experiment analyzes novel miscanthus hybrids and how their establishment on marginal land can be improved through agronomic interventions. Experiments took place at two sites in Germany: at Ihinger Hof, with a very shallow soil profile and high stone content, and at Reichwalde, where the soil was repurposed river sediment with low organic matter, high stone content, and a compacted lower horizon. These marginal conditions functioned as test cases for the improvement of miscanthus establishment agronomy. Four hybrids ( Miscanthus x giganteus , Gnt10, Gnt43, and Syn55) and agronomic treatments such as plastic mulch film, miscanthus mulch, inoculation with mycorrhizal fungi, and fertilization were tested in two years at both sites in 2021 and 2022. Specific weather conditions and the timing of planting were strong determinants of establishment success and no single treatment combination was found that consistently increased the establishment success. Plastic mulch films were found to hinder rather than help establishment in both these locations. Chipped miscanthus mulch caused nitrogen immobilization and stunted plant growth. At Ihinger Hof the novel seed-based miscanthus hybrid Gnt43 produced twice the biomass of other hybrids (7 t ha −1 ) in the first growing season. Gnt10 yielded well in 2021 and showed impressive tolerance to water stress in the summer of 2022. No treatment combination was found that consistently increased the establishment success of miscanthus hybrids across sites and years. Novel genotypes consistently outperformed the standard commercial miscanthus hybrid Miscanthus x giganteus . Gnt10 may be a promising candidate for the cultivation of water-stress-prone marginal lands, due to its isohydric behavior and high yield potential.
The daily relations between workplace anger, coping strategies, work outcomes, and workplace affiliation
(2025) Umbra, Robin; Fasbender, Ulrike
This study examines the daily relations among workplace anger, coping strategies, work outcomes, and employee dispositions using a conceptual framework based on affective events theory and cognitive perspectives on emotions. A sample of 214 full-time employees took part in a two-week study, contributing 1,611 daily observations through an experience sampling approach. Contrary to the assumption that workplace anger always detrimentally relates to work outcomes, the results showed a nonsignificant relation between workplace anger and workplace resource depletion, as well as a positive link between workplace anger and goal achievement. These relations were dependent on the coping strategies used by employees in response to anger-inducing situations, as well as their attitudes toward workplace affiliation. These findings suggest the need to expand affective events theory to include coping strategies as a mediator between affective responses and work outcomes. They also highlight the importance of integrating employee-level factors into organizational research models.
Enhanced crop diversity but not smaller field size benefit bats in agricultural landscapes
(2025) Hiller, Thomas; Gall, Friederike; Grass, Ingo; Hiller, Thomas; Ecology of Tropical Agricultural Systems, University of Hohenheim, Stuttgart, Germany; Gall, Friederike; Ecology of Tropical Agricultural Systems, University of Hohenheim, Stuttgart, Germany; Grass, Ingo; Ecology of Tropical Agricultural Systems, University of Hohenheim, Stuttgart, Germany
Context: Farmland biodiversity continues to decline due to the expansion and intensification of agriculture. Historically, efforts to conserve farmland biodiversity have focused on conserving habitats outside agricultural production areas. More recently, attention has turned to the conservation potential of the cropland matrix, where reducing field size and increasing crop diversity to promote crop heterogeneity can significantly benefit farmland biodiversity. Bats are one group of farmland species that have experienced dramatic declines over recent decades. Objectives: Here we investigated the effects of crop heterogeneity (crop diversity, field size) and landscape structural elements (e.g. length of linear structures, distance to forest, proportion of semi-natural habitat) on the activity of bat functional groups. Results: Increasing crop diversity led to greater bat activity, especially for open space foraging bats. However, contrary expectations, bat activity was not affected by heterogeneity in crop configuration, i.e. field edge density. Furthermore, structural landscape elements, including hedgerows and distance to forest, were important predictors of bat activity, especially for species that hunt in highly cluttered spaces. While crop diversity clearly benefited bat activity, the lack of effect of crop configurational heterogeneity on bat foraging activity may suggest heterogeneityarea trade-offs and intensive pesticide use in small-scale vegetable production. Conclusions: Therefore, in addition to maintaining high levels of crop diversity, promoting hedgerows and tree lines between farmland and woodland may facilitate bat activity across the agricultural landscape matrix. The combination of high crop heterogeneity and structural elements provides favorable hunting grounds for bats and may promote their conservation in agricultural landscapes.