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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

Environmental research is facing a drastic increase of available high-quality data, not the least due to the eLTER activities. Here simultaneous time series of numerous observables from the atmosphere, soil, streams, lakes and groundwater, etc., and comprising both abiotic and biotic variables will be made available from hundreds of sites. On the one hand quality control of these large data sets becomes a major challenge. On the other hand, though, it opens up completely new options for science as long as some key problems are solved:· How to differentiate between different effects?· How to deal with the filter effects of environmental systems?· How to identify unexpected relationships that a model would not depict?However, environmental sciences still lack a toolbox of approved integrated exploratory data analysis approaches to tackle these challenges in a systematic way. Here we suggest a combination of different methods that proved very efficient both in terms of data quality control and of exploratory data analysis for large sets of time series. Examples will be presented from the AgroScapeLab Quillow (LTER site DE-07-UM, Germany) and the Hurdal ICOS and ICP Forest Level II site (Norway). The Hurdal site is planned to be established as an elTER site as well.Any change of boundary conditions, of input fluxes, emerging invasive species etc. (termed “signal propagation” for short) in environmental systems is subject to filtering effects. A key feature thereof is low-pass filtering. Here we suggest the new Cumulative Periodogram Convexity (CPC) index to quantify the effect size for comparison of various time series. Principal Component Analysis of time series (termed Empirical Orthogonal Function approach in climatology) is suggested as another decisive step. Loadings on single components can be used for assessing the size of single effects on observed time series. Visualization of the communalities and of similarities between different observables and sites in a combination of Self-Organizing Maps and Sammon Mapping allows a rapid survey of some tens to hundreds of time series at a glance, e.g., for quality control. Additional consideration of the CPC index proved a powerful tool for identification of the respective key drivers and of the pathways of signal propagation through environmental systems, comprising both biotic and abiotic observables. Applying machine learning approaches to principal components rather than to the raw data facilitates developing a better understanding of complex interactions in environmental systems. To conclude, we see great potential in a systematic combination of existing approaches deserving to be explored further.

Abstract

Drought stress disrupts plant growth, metabolism, and reproduction, with devastating effects on crop productivity worldwide. Blackcurrant, although rich in health-promoting compounds, is highly vulnerable to water deficits, often producing fewer flowers and aborting developing fruit. Previous transcriptome studies provided only fragmented insights, and no reference genome existed for the Grossulariaceae family until now. Without such genomic tools, identifying precise stress-responsive genes and linking them to metabolite dynamics remained challenging. Based on these challenges, there is a pressing need to conduct integrated genome-scale, transcriptomic, and metabolomic studies to uncover blackcurrant’s drought response mechanisms.

Abstract

Synthetic plastics of petrochemical origin pose serious health risks to humans and animals, along with creating unwarranted stress on the environment. Recent years have witnessed the enormity of the depletion of natural resources to produce synthetic plastics. Of late, biodegradable bio-packaging materials are gaining attention due to stringent regulations against the usage of single-use plastics and microplastic deposition in the environment. This has led to the development of sustainable, eco-friendly, cost-effective biopackaging materials (mainly biodegradable bioplastics). Though certain drawbacks persist, the use of bio-packaging materials in food industries offers a lower carbon footprint, presents an environmentally friendly solution, and is cost-effective, especially when sustainable sources of raw materials are used. In this regard, agri-food industry-generated biomass/feedstock (wastes and processing by-products) has been explored and efficiently valorized to produce biodegradable plastics. Packaging solutions derived from agri-food wastes and by-products represent an innovative approach to address both resource efficiency and environmental-friendliness and support the circular economy concepts. This chapter aims to provide information on current developments in packaging solutions available in food industries, challenges, and opportunities for the future.

Abstract

Sweet cherries are grown in areas with suitable local climatic conditions up to 60°N in Norway. All orchards have high density planting systems and are rain covered from the bloom to the end of the harvest. All orchards are fertigated and the production is aimed to supply the domestic market with high quality fruit from early July and to the end of August. At NIBIO Ullensvang a large number of sweet cherry cultivars and advanced selections from worldwide breeding programs have been evaluated continuously since 1959. However, despite of relatively extensive list of recommended cultivars, cv. 'Lapins' has become dominant with 60% of the total sweet cherry volume in Norway, and causes high pressure in the market when too much fruit are delivered at the same time. The most effective way to extend the cherry market season is an introduction and cultivation of new early or late ripening sweet cherry cultivars. During the last years, approximately fifty cultivars and advanced selections have been evaluated. Along with earlier recommended cultivars ‘Folfer’, ‘Van’, ‘Lapins’, ‘Regina’ and ‘Sweetheart’, the following cultivars can be recommended for extended testing commercially: a) for early season: ‘Adelka’ (for local market), ‘Sweet Aryana’ and ‘Bellise’ (primary for local market), b) for mid-season: ‘Edit’, ‘Brooks’ (limited testing) and ‘Grace Star’, c) for late season: ’SPC 342’, ‘LaLa Star’, ‘Royal Edie’, ‘Tamara’ and ‘Royal Helen’.

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Abstract

Litter decomposition is coupled to carbon (C) sequestration through C release to the atmosphere, C transformation and nutrient release to the soil. We investigated if clear-cutting has long-term effects on this vital ecological process and consequently on C dynamics in boreal forests using twelve pairs of previously clear-cut and near-natural forests. Three litterbag experiments were conducted using (I) standardised spruce and bilberry litter, (II) melanised and non-melanised fungal necromass and (III) rooibos and green tea. We found weak and inconsistent effects of harvesting history, that did not depend on litter quality or mesofauna exclusion. Litter quality was more important in explaining net mass remaining for fungal necromass than for aboveground plant litter. Mesofauna exclusion had only marginal effects on initial litter decomposition. Results obtained with the highly standardised Tea Bag Index were not readily comparable to those of the plant litter or fungal necromass and we therefore question its use in this regional context. Further, we show that net mass or C remaining in the litterbags do not correlate consistently with in situ soil respiration. This finding is discussed in relation to previous measurements of soil C fluxes from the same system. In conclusion, we suggest that potential disturbances to the physical environment or the capacity of the decomposer community to facilitate litter decomposition are no longer clearly evident when clear-cut stands approach maturity.

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Abstract

ABSTRACT Aim We investigated the biogeographic history and diversification dynamics of Afrocarduus , an Afromontane–Afroalpine genus endemic to eastern Africa. We aimed to assess the roles of geographic isolation, habitat transitions, and ecological speciation in shaping current diversity. Location The Afromontane and Afroalpine regions of East Africa and Ethiopia are situated along the Great Rift Valley system. Taxon Afrocarduus (Compositae: Carduinae), a genus comprising 18 endemic species. Methods We conducted a comprehensive taxonomic and geographic sampling of Afrocarduus , generating data from 489 nuclear loci. Phylogenomic and biogeographic ancestral estimation analyses were performed to infer the evolutionary history and historical biogeography of the genus. Results Afrocarduus originated in the Afromontane zone of eastern Africa during the Late Miocene (~10.7 Ma), with major diversification events occurring in the Early Pleistocene (~2.3 Ma). Most dispersal events occurred between neighbouring massifs, though occasional long‐distance dispersal between disjunct mountain systems was detected. The Turkana Depression and the Great Rift Valley have acted as major biogeographic barriers. Phylogenetic structure shows distinct clades occupying different regions. Ecological divergence between Afromontane and Afroalpine environments contributed to speciation, with at least six independent adaptations to Afroalpine conditions and multiple cases of ecological reversal. Stem loss, a trait associated with alpine habitats, evolved convergently in two clades. Closely related species often segregate by elevation or microhabitat within the same massif. Main Conclusions The diversification of Afrocarduus has been shaped by a combination of historical climate change, geographic isolation, and ecological adaptation. Our results emphasise the importance of ecological speciation and habitat transitions in Afrotemperate plant evolution and highlight the need for further research on understudied Afromontane taxa, especially under the threat of ongoing climate change.