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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2025

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Abstract

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Abstract

Soil bulk density (BD) is a macroscopic indicator frequently used to infer the soils’ pore system, a fundamental attribute of terrestrial environments that significantly affects processes such as infiltration, water retention and plant root development. Additionally, BD is essential for assessing the storage of various materials in soils and sediments, including carbon and nutrients. High bulk density, often a consequence of soil compaction, represents a form of soil degradation that diminishes the soil’s functional capacity. Therefore, effective management of soil BD is crucial for improving agricultural yields, safeguarding ecosystem services, preventing degradation, and preserving the overall integrity of the Earth’s system. This review synthesizes recent research on the packing behavior of granular materials to clarify the emergent property of soil BD. The findings yield an empirical model that links packing fraction to the shape and size ratio of particles. The results demonstrate that the model accurately captures the frequently observed exponential decrease in soil BD with increasing soil organic matter (SOM) content. While it is widely recognized that particle density influences BD, the analysis indicates that grain shape exerts a considerable effect, followed by the particle size ratio in granular media. The insights from this study aim to transform the perception of BD from a static notion to one that acknowledges how changes in the morphology of soil constituents, driven by factors such as root growth and decomposition, can result in variations in BD. As a result, BD may become increasingly sensitive to feedback from climate and land use changes as the geometry of SOM evolves.

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Empirical field data and simulation models are often used separately to monitor and analyse the dynamics of insect pest populations over time. Greater insight may be achieved when field data are used directly to parametrize population dynamic models. In this paper, we use a differential evolution algorithm to integrate mechanistic physiological-based population models and monitoring data to estimate the population density and the physiological age of the first cohort at the start of the field monitoring. We introduce an ad hoc temperature-driven life-cycle model of Bemisia tabaci in conjunction with field monitoring data. The likely date of local whitefly invasion is estimated, with a subsequent improvement of the model’s predictive accuracy. The method allows computation of the likely date of the first field incursion by the pest and demonstrates that the initial physiological age somewhat neglected in prior studies can improve the accuracy of model simulations. Given the increasing availability of monitoring data and models describing terrestrial arthropods, the integration of monitoring data and simulation models to improve model prediction and pioneer invasion date estimate will lead to better decision-making in pest management.

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Abstract

Digestate, a key byproduct of anaerobic digestion (AD), holds residual methane potential (RMP) that must be stabilized or recovered to prevent greenhouse gas emissions after field use. Thermal hydrolysis (TH), typically a pretreatment for AD, improves biogas production. This study assesses RMP in digestates from food waste (FW) and sewage sludge (SS) biogas plants, treated with TH at 160 and 190 °C. For the liquid fraction, FW digestate at 160 °C yielded 1.5 times more methane than untreated digestate, while SS digestate showed a threefold increase. The solid fraction of FW digestate at 160 °C had 1.4 times higher methane yield than untreated, but SS digestate produced less methane after TH. Adding sulfuric acid after TH increased phosphate release but reduced methane production in both digestates. Overall, TH as a post-treatment enhanced organic content release into the liquid fraction, enhancing methane yield, while acid addition improved phosphorus solubility, thereby enhancing digestate's nutrient value.