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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

Boreal forests are important carbon sinks and host a diverse array of species that provide important ecosystem functions.Boreal forests have a long history of intensive forestry, in which even-aged management with clear-cutting has been thedominant harvesting practice for the past 50–80 years. As a second cycle of clear-cutting is emerging, there is an urgentneed to examine the effects of repeated clear-cutting events on biodiversity. Clear-cutting has led to reduced numbers ofold and large trees, decreased volumes of dead wood of varied decay stages and diameters, and altered physical andchemical compositions of soils. The old-growth boreal forest has been fragmented and considerably reduced. Here,we review short- and long-term (≥50 years) effects of clear-cutting on boreal forest biodiversity in four key substrates:living trees, dead wood, ground and soil. We then assess landscape-level changes (habitat fragmentation and edge effects)on this biodiversity. There is evidence for long-term community changes af

Abstract

To document effects of High-Pressure-Sodium (HPS) and Light-Emitting Diodes (LED) lamps, six different cucumber cultivars (‘DeeRect’, ‘HiLight’, ‘Imea’, ‘Keirin’, ‘Shakira’ and ‘Topvision’) were grown hydroponically in a semi-commercial greenhouse compartment using standard HPS or LED supplemental top-light from December to March. A PPFD of 240 µmol m-2s-1, 20h a day, was used for both lamp types. In addition, plants were grown with or without LED inter-lighting (45 µmol m-2s-1, 20h a day). Global radiation during the experiment was less than 1.5 MJ m-2day-1. Setpoints for day and night temperatures were 24 and 21 oC respectively. CO2 concentration in the greenhouse was kept at 1100 ppm. Morphological traits (stem length, leaf area, leaf thickness, dry weights), yield (fruit fresh weight and number of fruits) as well as quality parameters were registered. Results show that the use of LED top-light reduced yield considerably compared to HPS top-light, mainly due to a reduction in the number of 1st class fruits harvested. Plants grown using HPS top-light were longer, had more internodes, a higher fruit weight, bigger leaf area and leaf area index (LAI) and ‘thinner’ leaves compared to plants grown using LED top-light. Light use efficiency (g FW mol PAR-1) was highest using HPS or a combination of HPS and LED inter-light and lowest using LED combined with LED inter-lighting, especially at the start of the harvesting period. Huge differences in yield reduction between different cultivars were observed. LED top light reduced the yield of ‘DeeRect’ with 35% and of ‘HiLight’ with 5% compared to HPS top light. Little differences in quality traits were observed between cultivars grown under HPS or LED lamps. However, inter lighting increased fruit weight and fruit quality (color, dry matter content, soluble solid content, chlorophyll content, vitamin C content and storage properties). Causes of differences between lamp types and effects on commercial greenhouse cucumber production in Norway are discussed.

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Abstract

Aim: This study sets out to understand the variability in larval traits of dispersive life stages of a famous invader, the European shore crab Carcinus maenas, in its native distribution range. Location: North East Atlantic coast from the Norwegian Arctic to the southern European distribution limit of C. maenas in Southern Spain. Taxon: European shore crab Carcinus maenas (Crustacea, Decapoda). Methods: We quantified latitudinal patterns in larval body mass, elemental composition (C and N content), and thermal tolerance of the first larval stage. We collected crabs from four populations spanning 25° of latitude (Vigo in Northern Spain; Bergen, Trondheim, and Bodø in Norway) and reanalysed published and unpublished data of body mass and elemental composition of additional populations from Germany, Wales, France, and Southern Spain. Furthermore, we used two laboratory experiments to test the thermal tolerance limits of the first larval stage from Vigo and the Norwegian populations. In the first experiment, we reared larvae from hatching to Zoea II at seven temperatures (9°C–27°C) and from hatching to LT50 at 6°C. In the second experiment, we exposed freshly hatched larvae acutely to increasing or decreasing temperatures (up to 40°C and down to 3°C). Results: Across the entire European range, we found a substantial increase in dry mass and carbon and nitrogen content of freshly hatched larvae with latitude. Norwegian populations exhibited higher survival at 9°C than the Vigo population. Furthermore, LT50 at 6°C increased from South to North. All populations showed high survival in the range 12°C–24°C but low survival at 27°C.

Abstract

Over the past decades, significant efforts have been made to promote the cultivation of legumes. Cultivation of legumes, particularly grain legumes, can reduce the use of mineral nitrogen fertilizers, enhance biodiversity, reduce dependence on imported feed proteins, and improve soil biological properties and humus content. Despite these efforts, grain legumes are still not widely grown. One major obstacle to legume cultivation is "legume fatigue". Legume fatigue limits the expansion of legume cultivation in many European regions. The exact causes of legume fatigue are not fully understood, but soil-borne diseases interacting with abiotic factors are believed to play a key role. Recent findings suggest that the balance between pathogen load and soil suppressiveness is critical. Some farms and regions do not report legume fatigue as a problem, while others experience severe limitations in legume production. Identifying the causes of this variation is urgent and requires a collaborative effort that covers different environments and includes comprehensive assessments of both biotic and abiotic factors. In a recently launched project, LeFaSus, a network of farms and long-term experiments has been established to identify the primary factors contributing to legume fatigue. This network spans a transect from southern to northern Europe, including Italy, Germany, Luxembourg, and Norway. The project aims to deliver a reliable set of indicators for both legume fatigue and disease-suppressive soils, linking these indicators to the management practices that likely influenced them. The background and plans for the project will be presented.