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.
2018
Authors
Athanasios Markou George D. ManolisAbstract
No abstract has been registered
Authors
Ingeborg Callesen Nicholas Clarke Andis Lazdinš Iveta Varnagiryte-Kabasinskiene Karsten Raulund-RasmussenAbstract
The long-term carrying capacity for biomass production is highly dependent on available soil resources. A soil test method for potential nutrient release capability was applied to 23 Nordic and Baltic forest soil profiles. The soils had coarse (10), medium (12) and fine (1) soil texture and most were podsolising. Extraction with dilute (0.1 M, 1:50 sample:solution ratio) nitric acid for 2 h was followed by 48 h and 168 h of extraction in soil samples from pedogenetic horizons. Dilute nitric acid solution was replaced after each step and release of mineral nutrient elements in solution was determined. C-horizon nutrient release (µmol g−1 fine earth, 0–218 h) was negatively correlated with mean annual temperature (MAT 0.5–8.5 °C) and for potassium (K) also mean annual precipitation (MAP 523–1440 mm y−1) suggesting a gradient in the mineralogy of the parent material that sediment transports during Pleistocene glaciations have not distorted. In B-horizons of sandy parent materials with felsic mineralogy cumulative nutrient release was positively correlated with pH and with Al and Fe release suggesting accumulation and stabilisation of nutrients in pedogenic products. E-horizons had less nutrient release capability than C-horizons, indicating a more weathered state of E-horizon parent material. Soil formation due to mineral dissolution and leaching of base cations and the gradient in parent material origin and weathering state both affected the observed pattern of nutrient release. On soils with very low mineral P resources (e.g. < 250 kg P ha−1 to 50 cm) by repeated dilute acid extraction, harvest of nutrient rich biomass will not be sustainable. However, it can’t be concluded that sites with high P availability by 0.1 M HNO3 can support an intensive harvest without compensation of P (and Ca) by fertilisation. Due to buffering of removed base cations in B-horizons, nutrient export with biomass may not be traceable as pH decline at decadal time scale. Therefore, the direct measurement of nutrient stocks by the extraction procedure (or other similar assessment of nutrient reserves by strong acid) is suggested as indicative for the mineral weathering capability of forest soils to recover from P and base cation depletion by biomass harvest.
Authors
Nenad Potocic Ivan Seletkovic Mladen Ognjenovic Tamara Jakovljevic Melita Percec Tadic Volkmar TimmermannAbstract
No abstract has been registered
Authors
Kris Verheyen Martin Bažány Ewa Chećko Markéta Chudomelová Déborah Closset-Kopp Patryk Czortek Guillaume Decocq Pieter De Frenne Luc De Keersmaeker Cecilia Enriquez Garcia Martina Fabšičová John-Arvid Grytnes Lucia Hederová Radim Hédl Thilo Heinken Fride Høistad Schei Soma Horváth Bogdan Jaroszewicz Edyta Jermakowicz Terezá Klinerova Jens Kolk Martin Kopecký Iwona Kuras Jonathan Lenoir Martin Macek František Máliš Tone Constance Martinessen Tobias Naaf László Papp Ágnes Papp-Szákaly Paweł Pech Petr Petřík Jindřich Prach Kamila Reczýnska Magne Sætersdal Fabien Spicher Tibor Standovár Krzysztof Świerkosz Ewa Szczęśniak Zoltán Tóth Karol Ujházy Mariana Ujházyová Pieter Vangansbeke Ondřej Vild Dan Wołkowycki Monika Wulf Lander BaetenAbstract
Aim: Revisits of non-permanent, relocatable plots first surveyed several decades ago offer a direct way to observe vegetation change and form a unique and increasingly used source of information for global change research. Despite the important insights that can be obtained from resurveying these quasi-permanent vegetation plots, their use is prone to both observer and relocation errors. Studying the combined effects of both error types is important since they will play out together in practice and it is yet unknown to what extent observed vegetation changes are influenced by these errors. Methods: We designed a study that mimicked all steps in a resurvey study and that allowed determination of the magnitude of observer errors only vs the joint observer and relocation errors. Communities of vascular plants growing in the understorey of temperate forests were selected as study system. Ten regions in Europe were covered to explore generality across contexts and 50 observers were involved, which deliberately differed in their experience in making vegetation records. Results: The mean geographic distance between plots in the observer+relocation error data set was 24 m. The mean relative difference in species richness in the observer error and the observer+relocation data set was 15% and 21%, respectively. The mean “pseudo-turnover” between the five records at a quasi-permanent plot location was on average 0.21 and 0.35 for the observer error and observer+relocation error data sets, respectively. More detailed analyses of the compositional variation showed that the nestedness and turnover components were of equal importance in the observer data set, whereas turnover was much more important than nestedness in the observer+relocation data set. Interestingly, the differences between the observer and the observer+relocation data sets largely disappeared when looking at temporal change: both the changes in species richness and species composition over time were very similar in these data sets. Conclusions: Our results demonstrate that observer and relocation errors are nonnegligible when resurveying quasi-permanent plots. A careful interpretation of the results of resurvey studies is warranted, especially when changes are assessed based on a low number of plots. We conclude by listing measures that should be taken to maximally increase the precision and the strength of the inferences drawn from vegetation resurveys.
Authors
Marianne StenrødAbstract
No abstract has been registered
Authors
Shota Masumoto Motoaki Tojo Satoshi Imura Maria-Luz Herrero Masaki UchidaAbstract
The parasitic fungus Rhytisma polare is a common parasite on leaves of the polar willow (Salix polaris) in the high-Arctic polar semi-desert of Spitsbergen, Norway. Because Rhytisma spp. generally requires saturation with free water to develop ascospores, it is unclear how R. polare has ecologically adapted to the Arctic desert, where such water is very limited. In this study, the response of R. polare to diferent water conditions on Spitsbergen was investigated during the summer months of June–August in 2012. Field and laboratory experiments demonstrated that free water availability from rainfall or snowmelt is essential to facilitate ascostromal maturation and ascospore dispersal in R. polare. The feld experiments also revealed that the dispersal of ascospores produced on fallen leaves did not extend beyond a few meters. These results suggest that the free water requirement combined with the short spore-dispersal distance constrains the local occurrence of R. polare in the Arctic desert to locations where free water from rainfall and snowmelt is present.
Abstract
No abstract has been registered
Authors
Arild AndersenAbstract
The present paper is the last in a series of four on the fauna of Agromyzidae in Norway, and deals with the genera Melanagromyza Hendel, 1920, Ophiomyia Braschnikov, 1897, Amauromyza Hendel, 1931, Aulagromyza Enderlein, 1936, Cerodontha Rondani, 1861, Chromatomyia Hardy, 1849, Liriomyza Mik, 1894, Metopomyza Enderlein, 1936, Napomyza Westwood, 1840 and Phytomyza Fallén, 1810. Ninety-six species are reported of which seventeen are reported new to the Norwegian fauna: Melanagromyza aeneoventris (Fallén, 1823), M. cunctans (Meigen, 1830), M. pubescens Hendel, 1923, M. submetallescens Spencer, 1966, Ophiomyia curvipalpis (Zetterstedt, 1848), O. ranunculicaulis Hering, 1949, Chromatomyia syngenesiae Hardy, 1849, Metopomyza interfrontalis Melander, 1913, M. xanthaspioides (Frey, 1946) , Phytomyza cecidonomia Hering, 1937, P. cirsii Hendel, 1923, P. clematidis Kaltenbach, 1859, P. fennoscandiae Spencer, 1976, P. isais Hering, 1937, P. origani Hering, 1931, P. pulsatillae Hering, 1924 and P. socia Brischke, 1881. In addition, new regional data is given for eighty species previously reported from Norway. The biology of the larva, when known, and the distribution in Norway and Europe are commented on species new to Norway. The Norwegian checklist for Agromyzidae now consist of 256 species.
Authors
Ruben Alexander PettersenAbstract
No abstract has been registered
Abstract
No abstract has been registered