Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2024
Forfattere
Jian LiuSammendrag
Det er ikke registrert sammendrag
Forfattere
Andrea Ponzecchi Gry Alfredsen Maria Fredriksson Emil Engelund Thybring Lisbeth G. ThygesenSammendrag
Acetylation is a commercialised chemical wood modification technology that increases the durability of wood against microbial attack. However, the details of how acetylation protects the wood structure from fungal degradation are still unclear. In this study, we tested the hypothesis that the resistance against microbial attack depends on the localisation of acetylation within the cell wall. The methodology involved two types of acetylation (uniform and lumen interface modification), which were analysed by lab-scale degradation with Rhodonia placenta, chitin quantification, infrared spectroscopy, and Raman microspectroscopy. The location of the acetylation did not affect overall mass loss during degradation experiments. Instead, the mass loss was related to the intensity of the treatment. However, chemical imaging of the interface acetylated specimens showed that degradation primarily took place in cell wall regions that were less acetylated. It was also observed that the fungus required more fungal biomass (i.e., fungal mycelia) to degrade acetylated wood than untreated wood. Based on dimensions and comparison to a reference spectrum, several cross-sections of hyphae located within lumina were discovered in the Raman images. These hyphae showed presence of chitin, water and chelated metals within their walls, and could be separated into an inner and an outer part based on their chemistry as seen in the spectra. The outer part was distinguished by a relatively higher amount of water and less chelated iron than the inner part.
Forfattere
Johan Asplund Jenni Nordén O. Janne Kjønaas Rieke Lo Madsen Lisa Fagerli Lunde Tone Birkemoe Eivind Kverme Ronold Milda Norkute Ulrika Jansson Damian Petkovic Karlsen Anne Sverdrup-Thygeson Inger Skrede Ine-Susanne Hopland Methlie Sundy Maurice Ulrik Geiran Botten Regine Jusnes Krok Håvard Kauserud Line NybakkenSammendrag
The history of forestry in Fennoscandia spans five centuries, with clear-cutting being the dominant practice since the mid-20th century. This has led to a significant transformation of the forest landscape. In this study we investigated long-term effects of clear-cutting on forest structure and dead wood volumes. We established twelve pairs of spruce forest sites in southeastern Norway, each pair constituting of a mature, previously clear-cut stand and its near-natural counterpart with similar edaphic factors. The near-natural stands had 2.8 times higher volumes of dead wood and a larger proportion of dead wood in late stages of decay. The near-natural stands had on average 36.8 ± 9.1 m3 ha−1 of downed dead wood and 24.1 ± 6.2 m3 ha−1 of standing dead wood. Corresponding numbers for the previously clear-cut stands were 10.2 ± 2.8 m3 ha−1 and 11.9 ± 3.7 m3 ha−1. Forests with lower volumes of dead wood often also had lower connectivity of old spruce forests, which potentially have further negative effects on biodiversity. Furthermore, near-natural stands displayed greater tree size heterogeneity, resulting in a wider variation in light conditions. While no difference was observed in living tree volume, we found only weak evidence for higher basal area in the previously clear-cut stands, which had a higher stem density with more slender stems and shorter crowns. Our findings suggest that managed forests do not develop structures typical of near-natural forests before they become mature for logging. We stress the importance of a thorough site selection for studies of management effects, as forest management history may be confounded with productivity and other edaphic factors. Experimental designs like ours are vital for testing how differences in structure and deadwood volumes, driven by forest management, translate into variations in biodiversity, carbon sequestration and ecosystem functioning in future studies.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Line Nybakken YeonKyeong Lee Dag Anders Brede Melissa Magerøy Ole Christian Lind Brit Salbu Jorunn Elisabeth OlsenSammendrag
Det er ikke registrert sammendrag
Forfattere
Pablo Moreno-García Flavia Montaño-Centellas Yu Liu Evelin Y. Reyes-Mendez Rohit Raj Jha Robert P. Guralnick Ryan Folk Donald M. Waller Kris Verheyen Lander Baeten Antoine Becker-Scarpitta Imre Berki Markus Bernhardt-Römermann Jörg Brunet Hans Van Calster Markéta Chudomelová Deborah Closset Pieter De Frenne Guillaume Decocq Frank S. Gilliam John-Arvid Grytnes Radim Hédl Thilo Heinken Bogdan Jaroszewicz Martin Kopecký Jonathan Lenoir Martin Macek František Máliš Tobias Naaf Anna Orczewska Petr Petřík Kamila Reczyńska Fride Høistad Schei Wolfgang Schmidt Alina Stachurska-Swakoń Tibor Standovár Krzysztof Świerkosz Balázs Teleki Ondřej Vild Daijiang LiSammendrag
Biological nitrogen fixation is a fundamental part of ecosystem functioning. Anthropogenic nitrogen deposition and climate change may, however, limit the competitive advantage of nitrogen-fixing plants, leading to reduced relative diversity of nitrogen-fixing plants. Yet, assessments of changes of nitrogen-fixing plant long-term community diversity are rare. Here, we examine temporal trends in the diversity of nitrogen-fixing plants and their relationships with anthropogenic nitrogen deposition while accounting for changes in temperature and aridity. We used forest-floor vegetation resurveys of temperate forests in Europe and the United States spanning multiple decades. Nitrogen-fixer richness declined as nitrogen deposition increased over time but did not respond to changes in climate. Phylogenetic diversity also declined, as distinct lineages of N-fixers were lost between surveys, but the “winners” and “losers” among nitrogen-fixing lineages varied among study sites, suggesting that losses are context dependent. Anthropogenic nitrogen deposition reduces nitrogen-fixing plant diversity in ways that may strongly affect natural nitrogen fixation.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Virve Ravolainen Ingrid Marie Garfelt Paulsen Isabell Eischeid Jennifer Sorensen Forbey Eva Fuglei Tomás Hájek Brage Bremset Hansen Leif Egil Loe Petr Macek Jesper Madsen Eeva M Soininen James David Mervyn Speed Audun Stien Hans Tømmervik Åshild Ønvik PedersenSammendrag
Herbivores play a crucial role in shaping tundra ecosystems through their effects on vegetation, nutrient cycling, and soil abiotic factors. Understanding their habitat use, co-occurrence, and overlap is therefore essential for informing ecosystem-based management and conservation. In the High Arctic, only a marginal proportion of the land area is vegetated, and climate change is impacting herbivore population sizes and their habitats. In this study, we assessed the spatial habitat overlap of a vertebrate herbivore community based on: 1) regional predictive summer habitat suitability models for the resident Svalbard reindeer (Rangifer tarandus platyrhynchus), resident Svalbard rock ptarmigan (Lagopus muta hyperborea), and the migratory pink-footed goose (Anser brachyrhynchus), and 2) presence of fecal pellets, reflecting the annual habitat use of reindeer, ptarmigan, and geese, including the pink-footed goose and barnacle goose (Branta leucopsis). Our findings revealed that only small proportions of the available land cover (~ 12516 km2; all land area excluding glaciers and freshwater) are suitable for each of the species (habitat suitability [HS] > 0.5): reindeer (22%), ptarmigan (11%), and pink-footed goose (4%). Overlapping suitable habitat [HS > 0.5] for reindeer and goose accounted for only 3% of the total vegetated area (~ 8848 km2) and was primarily found in heath and moist habitats dominated by mosses, graminoids, and herbaceous plants. The overlapping suitable habitat for reindeer and ptarmigan covered 8% of the vegetated area, predominantly in higher elevation ridges with vegetation on drier substrates. The shared habitat for ptarmigan and goose, and all three species of herbivores, was less than 1% of the vegetated area. Additionally, an assessment of fecal pellets suggested that the highest overlap in habitat use among reindeer and goose occurred in bird cliff moss tundra, followed by moss tundra and heath habitats. The small proportion of the vegetated area suitable for all three herbivores indicates a high degree of habitat differentiation. Therefore, different habitats need to be considered for the management and conservation of resident and migratory herbivore species in this High Arctic Archipelago. Moreover, our results underscore the importance of the small but productive parts of the landscape that were used by all herbivores. Goose, habitat suitability, management, ptarmigan, reindeer
Forfattere
Pia Heltoft Thomsen Kristian Sæther Mari Henrikke Vandsemb Anne-Helen Kalhovd Leif Skjønsby Halvor AlmSammendrag
Det er ikke registrert sammendrag
Forfattere
Astrid Solvåg Nesse Agnieszka Jasinska Ketil Stoknes Stine Göransson Aanrud Kristin Meland Risinggård Roland Kallenborn Trine Aulstad Sogn Tomasgaard Aasim Musa Mohamed AliSammendrag
The uptake dynamics of two sulfonamide antibiotics, two fluoroquinolone antibiotics, and the anticonvulsant carbamazepine during the cultivation of two species of edible mushrooms (Agaricus subrufescens and A. bisporus) was investigated. None of the antibiotics were accumulated by the mushrooms, while carbamazepine and its transformation product carbamazepine-10,11-epoxide were taken up by A. bisporus fruiting body but only in small amounts (up to 0.76 and 1.85 μg kg−1 dry weight, respectively). The sulfonamides were quickly removed from the mushroom growth substrate, while the recalcitrant fluoroquinolones and carbamazepine were only partially removed. Dissipation half-lives were generally lower for A. subrufescens than A. bisporus, but A. subrufescens was also grown at a slightly higher culture temperature. A. subrufescens also showed a lower uptake of contaminants. Comparison of maximum dietary intake with other common exposure sources showed that these mushrooms can safely be eaten although produced on a polluted substrate, with respect to the investigated compounds.