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
Authors
Lorène J. Marchand Jožica Gričar Paolo Zuccarini Inge Dox Bertold Mariën Melanie Verlinden Thilo Heinecke Peter Prislan Guillaume Marie Holger Lange Jan Van den Bulcke Josep Penuelas Patrick Fonti Matteo CampioliAbstract
In the temperate zone, deciduous trees exhibit clear above-ground seasonality, marked by a halt in wood growth that represents the completion of wood formation in autumn and reactivation in spring. However, the growth seasonality of below-ground woody organs, such as coarse roots, has been largely overlooked. Here we use tree monitoring data and pot experiments involving saplings to examine the late-season xylem development of stem and coarse roots with leaf phenology in four common deciduous tree species in Western Europe. Coarse-roots wood growth continued throughout the winter whereas stem wood growth halted in autumn, regardless of the tree species, experimental setting or location. Our results do not indicate a clear temperature constraint on below-ground wood growth, even during prolonged periods with soil temperatures lower than 3 °C. The continuous diferentiation of xylem root cells in autumn and winter suggests that the non-growing season does not exist sensu stricto for all woody organs of angiosperm deciduous tree species of the temperate zone. Our fndings hold implications for understanding tree functioning, in particular the seasonal wood formation, the environmental controls of tree growth and the carbon reserves dynamics.
Authors
Eirik Gottschalk Ballo William J. D’Andrea Helge Irgens Høeg Kjetil Loftsgarden Manon Bajard Sabine Eckhardt Massimo Cassiani Nikolaos Evangeliou Jostein Bakke Kirstin KrügerAbstract
Previous Common Era (i.e., the past 2000 years) climate reconstructions from Fennoscandia have focused on northern and central areas, with scarce data from the southern areas. Using varved sediments from Lake Sagtjernet in southeastern Norway, we developed a hydrogen isotope record from sedimentary leaf waxes (n-alkanes) as a proxy for hydrogen isotopes in precipitation, which we interpret as an indicator of temperature variability over the past 2000 years. The climate reconstruction provides high, decadal resolution for the period 360–770 CE, allowing critical evaluation during the Dark Ages Cold Period (around 300–800 CE) and a cooling during the 6th century, previously suggested as the coldest period of the Common Era. Our results reveal that the most rapid drop in temperature occurred from 536 to 545 CE (+74/-90 years), corresponding in time to the 536 and 540 CE volcanic eruptions. We also document an inferred cold interval that persisted from around 650 to 710 CE (+72/-90 years). While past studies have suggested prolonged cooling during the Dark Ages Cold Period, our findings show that, on average, the climate during 360–770 CE was similar to the Common Era average in the Lake Sagtjernet record. To explore socio-environmental interactions throughout the past 2000 years, we present a pollen-based environmental reconstruction and integrate it with archaeological evidence from around Lake Sagtjernet. These analyses reveal significant societal activities such as land clearing, cereal cultivation, and large-scale iron production, which drastically altered the landscape in the Viking Age (around 800–1050 CE) and the first half of the Norwegian Middle Ages (around 1050–1350 CE). Modern cultivation practices following the Black Death (1349–1350 CE) were first established around 1470 CE and increased continuously until around 1940 CE. Intensification of societal activities through the past millennium, including iron production and modern cultivation, occurred during both warmer (Medieval Climate Anomaly; 950–1250 CE) and colder (Little Ice Age; 1450–1850 CE) periods.
Authors
Richita Saikia Athanasios Kaldis Carl Jonas Jorge Spetz Basanta Kumar Borah Andreas VoloudakisAbstract
Plant viruses utilize a subset of host plasmodesmata-associated proteins to establish infection in plants. In the present study, we aimed to understand the role of two plant genes, one encoding a putative plasmodesma located protein (PDLP) and a homolog of soybean gene regulated by cold 2 protein (SRC2) during Cucumber mosaic virus (CMV) infection. Virus-induced gene silencing (VIGS) was used to silence PDLP and SRC2 genes in Nicotiana benthamiana and in two related solanaceous plants, N. tabacum and Capsicum chinense Jacq. (Bhut Jolokia). Up to 50% downregulation in the expression of the PDLP gene using the TRV2-PDLP VIGS construct was observed in N. benthamiana and N. tabacum while, using the same gene construct, 30% downregulation of the target mRNA was observed in C. chinense. Similarly, using the TRV2-SRC2 VIGS construct, a 60% downregulation of the SRC2 mRNA was observed in N. benthamiana, N. tabacum, and a 40% downregulation in C. chinense as confirmed by qRT-PCR analysis. Downregulation of the PDLP gene in N. benthamiana resulted in delayed symptom appearance up to 7–12 days post inoculation with reduced CMV accumulation compared to the control plants expressing TRV2-eGFP. In contrast, SRC2-silenced plants showed enhanced susceptibility to CMV infection compared to the control plants. Our data suggest that the PDLP gene might facilitate infection of CMV, thus being a susceptibility factor, while the SRC2 gene could play a role in resistance to CMV infection in N. benthamiana.
Authors
Bolette BeleAbstract
This thesis aims to document, discuss, and get a deeper understanding of how heritage values and natural resources in the summer farming landscape interact and can be maintained for the future. The integrated relationship between food production, landscape, biodiversity, and traditional ecological knowledge has been the focus. Through a mixed method approach and by using qualitative and quantitative data in eight papers (Paper I-VIII), the study contributes to a collection of topics essential for a more integrated understanding of the traditional land use system and products and services provided to society. NO: Hovedformålet med denne avhandlingen har vært å dokumentere, diskutere, og øke forståelsen for samspillet mellom kulturarven og naturressursene i det norske seterlandskapet, og hvordan de kan ivaretas for framtida. Det har blitt satt et spesielt fokus på sammenhengene mellom matproduksjonen, landskapet, biodiversiteten, og den tradisjonelle økologiske kunnskapen. Ved hjelp av kvalitative og kvantitative data og metoder har åtte artikler (Paper I-VIII) gitt resultater som til sammen skaper en mer integrert forståelse av det norske seterlandskapet og de produkter og tjenester som seterbruket bidrar med til samfunnet.
Abstract
Urban agriculture has the potential to contribute to more sustainable cities, but its impacts are complex and varied. By implementing robust monitoring systems, cities can better understand the true effects of urban farming initiatives. This evidence can then inform smarter policies and more effective urban planning strategies.
Authors
Emma Slone Jessica Green Navneet Kaur Darrin L. Walenta Nicole P. Anderson Casey Cruse Seth J. DormanAbstract
Agrotis ipsilon (Lepidoptera: Noctuidae) is a significant pest in Oregon grass seed and vegetable production systems. Effective management of this species relies on timely foliar insecticide applications targeting immature A. ipsilon larvae before crop damage is observed. Regionally specific phenological models serve as a critical component of effective areawide pest management plans to inform the timing of pest monitoring and management action. Seasonal modeling of A. ipsilon phenology is complicated by their migratory behavior and limited knowledge of temperature-dependent development on affected crop hosts. Growth chamber experiments at five constant temperatures (12 to 32°C) were conducted to determine the temperature-dependent development of A. ispsilon life stages on an artificial and perennial ryegrass diet. The completion of one A. ipsilon generation (egg-to-adult) required 658.71 ± 31.49, 601.98 ± 16.01, 648.47 ± 21.35 degree days with a base temperature threshold of 9.8°C for artificial diet, perennial ryegrass diet, and across both diet types, respectively. The timing of migrant adults was predicted with surface air temperature using non-linear regression with A. ipsilon abundance data collected from pheromone-baited traps in 77 total commercial grass seed (n = 57) and vegetable (n = 20) production fields across 19 sampling years (1996 to 2023). Developmental parameters and predictions of adult arrival were used to develop general and grass seed specific phenology model projections for A. ipsilon populations in Oregon. Regionally validated phenology models can be incorporated into decision support tools to forecast the spatiotemporal occurrence of crop-damaging life stages of priority insect pests.
Authors
Céline ReboursAbstract
No abstract has been registered
Authors
Erik J. JonerAbstract
No abstract has been registered
Authors
Jakob J. Assmann Pil B. M. Pedersen Jesper E. Moeslund Cornelius Senf Urs A. Treier Derek Corcoran Zsofia Koma Thomas Nord-Larsen Signe NormandAbstract
Forest ecosystems will play a critical role in achieving policy targets for biodiversity and conservation, such as those set out in the EU Biodiversity strategy for 2030. However, practitioners need to know where forests of high conservation value are to make the best-informed decisions about which forests to prioritize. Here, we combine airborne LiDAR (airborne laser scanning/ALS), optical satellite imagery, and gridded datasets on soil and water availability with machine learning models to predict forests' conservation value across Denmark. We then use change-detection algorithms to identify forests that had been disturbed since the collection of the LiDAR data to produce up-to-date estimates for the year 2020. Our models reached a high predictive capacity (82% accuracy) and suggested that 1982 km2 (~31%) of Denmark's forests were of potential high conservation value. Our study demonstrates the utility of data fusion approaches to identify forest areas of high value for conservation at fine spatial resolutions (~10–100 m) and nationwide extents. However, uncertainties remain in our approach. Hence, our findings should be used to guide field-based assessments to confirm the in situ conservation value of the forests. Only in combination with such in situ data will approaches like ours enable decision makers to better protect forest biodiversity.
Abstract
Quantifying the impact of biochar on carbon persistence across soil textures is complex, owing to the variability in soil conditions. Using artificial soils with precise textural and mineral compositions, we can disentangle the effects of biochar from the effects of soil particle size. We can show that biochar application significantly reduces the early-stage carbon mineralization rates of plant residues in various soil textures (from 5 % to 41 % clay) but more significantly in sandy soils. Clay and silt particles alone also reduce C mineralization, but the magnitude of the changes is negligible compared to the impact of biochar. This finding suggests that biochar can compensate for the lack of clay in promoting C persistence in soil systems. This short report contributes substantially to understanding soil texture and biochar application interactions.