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.
2026
Authors
Karen Ane Frøyland Skjennum Jan Mulder Gijsbert Dirk Breedveld Thomas Hartnik Nicolas Estoppey Erlend Grenager SørmoAbstract
The present study investigates the long-term immobilization efficiency of biochar on target per- and polyfluoroalkyl substances (PFAS) and precursors in well-drained soils contaminated by aqueous film-forming foam (AFFF) (Ʃ27PFAS = 1624 ± 276 µg/kg) over 2 years. The total oxidizable precursor (TOP) assay revealed a large precursor reservoir in the soil. Fifteen outdoor field-scale columns were packed with contaminated soil (48 kg) without (control columns, triplicates) and with biochar amendments: Three sewage sludge-based biochars were homogeneously mixed into the soil at a 1% (w/w) dose in triplicate columns. One of the biochars was additionally applied as a barrier at the column base (1% w/w) in a separate set of columns. The best-performing biochar immobilized long-chain PFAS by 91.0 ± 35.0% and short-chain PFAS by 96.7 ± 32.9%, possibly due to a well-developed porosity. Compared to the control columns, the fluctuating PFAS leaching were negligible in columns amended with the best-performing biochar, but the immobilization efficiency of short-chain PFAS decreased after one year (from 97.8% to 74.2%). Applying biochar as a barrier was two times more effective than homogenous mixing, and the effect was most pronounced for long-chain PFAS. Our findings suggest that biochar may immobilize precursors, notably CF3-CF5 precursors, to the same extent or better than their typical target perfluoroalkyl acids transformation products. More research is, however, needed to confirm these trends. Going beyond simple lab experiments, this study suggests that biochar is a promising solution for PFAS remediation and brings the technology closer to field application.
Authors
Ulrika Jansson Asplund Damian Petkovic Karlsen Anne Krag Brysting Rune Halvorsen Håvard Kauserud O. Janne Kjønaas Johan AsplundAbstract
No abstract has been registered
Authors
Ming Yu Sebastian Kepfer-Rojas Yamina Micaela Rosas Teresa Gómez de la Bárcena Inger Kappel Schmidt Per Gundersen Ludovica D'Imperio Carsten W. Mueller Lars VesterdalAbstract
No abstract has been registered
Authors
L. Duncanson P. M. Montesano A. Neuenschwander A. Zarringhalam N. Thomas D. M. Minor M. A. Wulder J. C. White E. Guenther T. Feng V. Leitold S. Hancock J. Armston Stefano Puliti A. I. Mandel S. Shah C. Silva M. Purslow J. Bruening Johannes Breidenbach Erik Næsset Svetlana Saarela N. Hunka J. R. Kellner S. P. Healey D. Schepaschenko J. Wallerman C. S. R. Neigh N. Carvalhais R. DubayahAbstract
Forest aboveground biomass Density (AGBD) maps provide important constraints on climate and carbon cycle models and enable the long-term monitoring of carbon stocks. NASA's latest spaceborne lidar instruments provide unprecedented observations of forest structure that are used to compile spatially continuous, locally trained maps of circa 2020 AGB density and stock. To address a geographical limitation of the International Space Station deployed GEDI instrument, herein we map high northern latitude forests with a fusion of NASA's ICESat-2 mission, Harmonized Landsat Sentinel-2 (HLS), and Copernicus GLO-30 topographic data. We report a domain-wide estimate for boreal forests of 72.96 +/− 0.61 Pg AGB. Combining these maps with those of tropical and temperate forests from GEDI products provides a global estimate of 2020 biomass stocks of 593.49 +/− 11.47 Pg AGB. We analyze biomass means and totals across the boreal domain in different land cover types, slope classes, and ecoregions. We compare these products to national estimates of AGB stocks for high latitude countries, finding good general agreement between national reports and EO-based estimates, particularly for countries with robust National Forest Inventories (NFIs) and boreal forests, while underestimation of high AGBD in tall, dense forests remains a challenge for AGBD mapping. Satellite products can be used to support wide area estimation of aboveground biomass, and the maps described here provide insights into carbon stocks, patterns, and dynamics at scales relevant to forest management. These open access data products serve as a baseline to assess future changes associated with drought, fire, insects, deforestation, and degradation.
Authors
José Luís Trevizan Chiomento Nícolas Alberton Mandelli Ana Júlia Schroeder Ely Matheus Welter Henrique Didó Maria Antônia Lacourt Oliveira Bruna Jirkowski Francisco Wilson Reichert Junior Mateus Possebon Bortoluzzi Rafael Rieder Thomas dos Santos Trentin Anita SønstebyAbstract
This study investigated the effect of arbuscular mycorrhizal fungi (AMF), Trichoderma harzianum, and their combinations on yield and quality of strawberry fruits in a soilless cultivation system. Six treatments were applied, control (no biostimulants), T. harzianum (TH), Claroideoglomus etunicatum (CE), a multispecies mycorrhizal community (IP CS), TH + CE, and TH + IP CS, arranged in a randomized block design with four replicates. While total fruit yield was not significantly affected, the application of T. harzianum, either alone or in combination with AMF, enhanced cumulative fruit production. The use of C. etunicatum improved sugar content and the sugar/acid ratio by 28% and 31%, respectively, compared to the control. Biostimulant treatments also increased total phytochemical content, particularly with the multispecies inoculant IP CS (increased anthocyanin content by 39% compared to the control) and the combinations TH + CE (flavonoid content 41% higher than the control) and TH + IP CS (flavonoid content 39% higher than the control). Multivariate analysis grouped the treatments into two groups, with the control (no biostimulants) forming a distinct group. In conclusion, biostimulation of ‘San Andreas’ strawberry plants improved fruit quality without significantly increasing yield. The combined use of AMF and T. harzianum is proposed as a sustainable strategy for enhancing fruit quality in soilless strawberry cultivation systems.
Authors
Milica Fotirić Akšić Mirjana Pešić Ilinka Pećinar Mihajlo Jakanovski Danijel Milinčić Aleksandar Kostić Marko Kitanović Uroš Gašić Dragana Dabić Zagorac Dušanka Milojković Opsenica Mekjell MelandAbstract
No abstract has been registered
Authors
Chen‐Jui Yang Tomas Funda Rajiv Chaudhary Zhi‐Qiang Chen Maximiliano Estravis Barcala Harry WuAbstract
Genetic differentiation among populations often varies significantly across the genome due to factors such as selection and recombination, resulting in a heterogeneous genomic landscape. However, variation in low‐differentiation regions—genomic valleys—remains poorly understood. Moreover, most insights into plant genomic landscapes come from flowering plants, while comparable genome‐wide studies in other taxa, such as conifers, remain limited. We analyzed whole‐genome sequencing data from 100 individuals of three pine species— Pinus banksiana , Pinus contorta , and Pinus nigra . We found substantial genome‐wide variation in recombination rates, with intergenic regions exhibiting higher recombination than genic regions, and rates decreasing with increasing distance from genes. Recombination rate was negatively correlated with gene length, driven primarily by intron length, suggesting that long introns in conifers may promote the retention of exceptionally long genes by maintaining low recombination in these regions. Genomic scans further revealed that genomic valleys are maintained through either balancing, background, or parallel selection. Additionally, multiple forms of selection were strongly associated with local recombination rate variation, highlighting the significant role of recombination in shaping patterns of genomic differentiation. Our findings provide new insight into the evolution and maintenance of extremely long genes in conifers. Moreover, the results indicate that allopatric selection in regions of low recombination is a major force structuring genomic variation in these species.
Authors
Radosav Cerović Milica Fotirić Akšić Milena Ðorđević Marko Kitanović Anđelija Obradović Mekjell MelandAbstract
No abstract has been registered
Authors
Rajiv Chaudhary Maximiliano Estravis Barcala Irena Fundova Tomáš Funda Zhi-qiang Chen Harry X. WuAbstract
Background Drought intensity and frequency are increasing under global warming in the boreal forests, and breeding for drought resistance will facilitate adaptation of new planting material to changing climate conditions. We used a tree-ring dataset of 559 individuals to study Scots pine genetic variation and the efficiency of genomic selection of drought-response traits (drought resistance, recovery and resilience), for the first time. From genotyping-by-sequencing (GBS), 31,101 SNPs were generated and used for the study. Results Significant genetic variation was detected for drought-response and other growth, wood-anatomy and wood density traits. Heritability estimates for wood-anatomical traits were higher than those for drought-response and growth traits. Genetic correlations between drought-response and wood-anatomical traits were generally high but mostly nonsignificant. In contrast, drought resistance and recovery showed positive and significant correlations with basal area increment and height. We found that the predictive ability and accuracy for drought-response traits were lower than those for wood-anatomical traits, and were comparable between GBLUP and ABLUP. Greater genetic gain per year can be achieved through genomic selection relative to pedigree-based selection if the generation interval is reduced. Conclusions The positive genetic correlation between drought-response and growth traits will enable simultaneous selection for improved growth and increased drought resistant trees in Scots pine breeding through either pedigreed-based and genomic selection.
Authors
Niklas Jan WickanderAbstract
Ethiopia suffers from severe soil degradation resulting from poor agricultural management practices, deforestation, cultivation on slopes, and heavy, erratic rainfall patterns. This degradation places substantial pressure on smallholder farmers through the loss of topsoil, which reduces soil fertility and diminishes the area of arable land available for cultivation. Smallholder farmers typically practice mixed crop-livestock system, in which animals are often kept on small plots of land during the dry season and fed crop residues, while being allowed to graze on communal lands during the rainy season. Livestock is important to Ethiopian livelihoods, with a large proportion of the population dependent on it. However, the high density of animals, combined with low forage production, exacerbates soil degradation through overgrazing on communal land and increased reliance on crop residues for feed, thereby reducing the return of organic matter to the soils. To address these issues, inclusion of perennial forage mixtures as leys has been proposed as a strategy to both improve livestock feed production and restore degraded soils while preventing further degradation. Plant mixtures, particularly of grasses and legumes, have well-documented benefits to enhance soil organic C (SOC) and nutrient content, reduce the risk of erosion by stabilizing soil structure, and increase forage yields and feed quality. Improved soil nutrient status due to plant inputs also stimulates soil microbial communities, increasing microbial activity and exoenzyme synthesis. This has positive ramifications for soil nutrient cycling and may help remediate degraded Ethiopian soils in low-input agricultural systems. However, the effects of different plant species mixtures in soils with varying chemical and mineralogical composition remain unclear and require further investigations to identify optimal plant mixtures for different soil types. This thesis aims to elucidate the effects of four forage plant species on selected soil parameters in degraded soils from two distinct Ethiopian regions, with a particular focus on soil microbial functions. The thesis comprises three papers, each with focus on different aspects of plant-soil-plant feedbacks in various settings: (I) the effects of plant diversity and biomass on microbial activity and nutrient cycling in a field experiment, (II) the effects of specific plant species inputs on soil microbial nutrient stoichiometry and nutrient cycling under controlled greenhouse conditions, (III) microbial carbon use efficiency (mCUE) in weathered soils under cultivation of perennial forage species in a greenhouse experiment. The thesis is based on three separate experiments: a field experiment in the Amhara and Sidama regions of Ethiopia, and both large- and small-scale factorial experiments in greenhouse using soils sampled from these regions. Two grasses (Urochloa hybrid cv. Cayman and Megathyrsus maximus) and two legumes (Desmodium intortum and Stylosanthes guianensis) were grown in the experiments described in Papers I and II, whereas only U. cv. Cayman and D. intortum were grown in the experiment described in Paper III. Soil chemical and physical characteristics were determined prior to the experimentation for all soils. Microbial nutrient status and its responses to plant input were assessed via analysis of exoenzyme activity (EEA), while specific microbial functions such as nitrification and denitrification were also measured. The plant effect on microbial C-turnover and growth was determined by using the 18O-H2O stable isotope probing (SIP) method, determining mCUE and microbial growth rate. Overall, plant inputs had generally positive effects on soil microbial functions, although responses varied considerably depending on initial soil properties. The strongest effects were typically observed in the more fertile Sidama soils, compared to the less fertile Amhara soils. The magnitude and nature of plant input effects also differed across the three studies. Plant species diversity and biomass had minor effects on soil microbial functions, while U. cv Cayman showed some positive effects on belowground functions in Hawassa soil (Paper I). Legumes, particularly S. guianensis, enhanced EEA which contributed positively to the soil microbial nutrient cycle (Paper II). Plant inputs affected mCUE only in the Sidama soils, with a positive effect of increased plant biomass on mCUE and a negative effect of the U. cv. Cayman × D. intortum mixture on mCUE (Paper III). In summary, the implementation of perennial forage mixtures had positive effects on soil microbial nutrient cycling, with potential long-term effects for soil health. However, these effects were soil-specific, with stronger responses and higher microbial activity in the more fertile, phosphorus (P) rich soils of the Sidama region. The low responsiveness of soil microbes to plant inputs in the Amhara region may be attributed to inherently low P availability. Alleviating P limitation may therefore be necessary before realizing the beneficial effects of perennial forage mixtures in P-limited soils. In addition, site-specific selection of plant species mixtures that can successfully establish and co-exist is recommended to achieve optimal plant performance and effective soil remediation.