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.
2010
Abstract
In European forests, standing stocks are currently higher than ever during the last decades, in part due to reduced logging or the abandonment of agricultural land. However, data from intensive monitoring plots reveal an increased growth even without direct human intervention.We used a set of 363 plots from 16 European countries to investigate the influence of environmental factors on forest growth: nitrogen, sulphur and acid deposition, temperature, precipitation and drought, for Norway spruce, Scots pine, common beech and European as well as sessile oak.We used existing information on site productivity, stand age and stand density to estimate expected growth. Relative tree growth, i.e., the ratio between actual growth within a five-year period and expected growth, was then related to environmental factors in a stepwise multiple regression.The results consistently indicate a fertilizing effect from nitrogen deposition, with roughly one percent increase in site productivity per kg of nitrogen deposition per ha and year, or 20 kg C fixation per kg N deposition. This was most pronounced for plots having soil C/N ratios above 25. We also found a positive albeit less clear relationship between relative growth and summer temperatures.From the study, we cannot conclude on any detrimental effects on growth from sulphur and acid deposition or from drought periods. A very recent study from the U.S., comprising 4800 plots and 24 tree species, confirms our results. However, we also show that the magnitude of N deposition effects on global forest C balance is currently a highly controversial matter, and comment on this debate. http://www.cef-cfr.ca/uploads/Colloque/Programme10_5.pdf
Authors
Adam ParuchAbstract
No abstract has been registered
Authors
Tao Zhao Paal Krokene Niklas Björklund Bo Långström Halvor Solheim Erik Christiansen Anna-Karin Borg-KarlsonAbstract
Constitutive and inducible terpene production is involved in conifer resistance against bark beetles and their associated fungi. In this study 72 Norway spruce (Picea abies) were randomly assigned to methyl jasmonate (MJ) application, inoculation with the bluestain fungus Ceratocystis polonica, or no-treatment control. We investigated terpene levels in the stem bark of the trees before treatment, 30 days and one year after treatment using GC–MS and two-dimensional GC (2D-GC) with a chiral column, and monitored landing and attack rates of the spruce bark beetle, Ips typographus, on the trees by sticky traps and visual inspection. Thirty days after fungal inoculation the absolute amount and relative proportion of (+)-3-carene, sabinene, and terpinolene increased and (+)-α-pinene decreased. Spraying the stems with MJ tended to generally increase the concentration of most major terpenes with minor alteration to their relative proportions, but significant increases were only observed for (−)-β-pinene and (−)-limonene. Fungal inoculation significantly increased the enantiomeric ratio of (−)-α-pinene and (−)-limonene 1 month after treatment, whereas MJ only increased that of (−)-limonene. One year after treatment, both MJ and fungal inoculation increased the concentration of most terpenes relative to undisturbed control trees, with significant changes in (−)-β-pinene, (−)-β-phellandrene and some other compounds. Terpene levels did not change in untreated stem sections after treatment, and chemical induction by MJ and C. polonica thus seemed to be restricted to the treated stem section. The enantiomeric ratio of (−)-α-pinene was significantly higher and the relative proportions of (−)-limonene were significantly lower in trees that were attractive to bark beetles compared to unattractive trees. One month after fungal inoculation, the total amount of diterpenes was significantly higher in putative resistant trees with shorter lesion lengths than in putative susceptible trees with longer lesions. Thus, terpene composition in the stem bark may be related to resistance of Norway spruce against I. typographus and C. polonica.
Abstract
The Lange Bramke catchment has been investigated as a monitored catchment for 60 years. However, its utilization history even dates back to medieval times, and is well documented in part. The intense interplay between ore mining, forestry, and water resources exploitation left remains such as scoriae piles and modified forest growth, e.g. due to local pollution at smelter locations. It is demonstrated that considering local land use history is important for a proper understanding and interpretation of modern monitoring data. A theoretical framework is proposed for the integration of the two data sources. This requires a joint approach combining two modelling paradigms, the functional one dominating in current ecosystem research, and an interactive one which best characterizes the human–environment relationship in historic times.
Authors
Signe Nybø Gregoire Certain Olav Skarpaas Jarle W. Bjerke Erik Framstad Markus Lindholm Jan-Erik Nilsen Ann Norderhaug Eivind Oug Hans Christian Pedersen Ann Kristin Schartau Ken Olaf Storaunet Gro Ingleid van der Meeren Iulie Aslaksen Steinar Engen Per Arild GarnåsjordetAbstract
No abstract has been registered
Abstract
AR18×18 is an area frame survey of land resources in Norway, methodologically linked to the Lucas survey carried out by Eurostat (Eurostat 2003). The purpose of the survey is to establish an unbiased and accurate land cover and land use statistic providing a description of the state of land resources in Norway. The survey will also provide a baseline for future reports regarding changes in land resources – a national land resource accounting system. AR18×18 is based on Lucas (Land use/cover agricultural survey), a European area frame survey carried out in the EU countries by Eurostat. The sampling units of Lucas are points located on the intersections of an 18 × 18 kilometer grid mesh throughout Europe. Each of these points is the centre of a Primary Statistical Unit (PSU) of 1500 × 600 meters. The Lucas survey is carried out on ten sample points scattered within each PSU. The Norwegian modification of Lucas is to add a land cover survey of the whole PSU following the Norwegian system for vegetation and land cover mapping at intermediate scale (1: 20,000). [...]
Authors
Rebekka ØvstegårdAbstract
Dengue is the most rapidly spreading mosquito-borne viral disease in the world, with an estimated 50 million infections occurring annually. Dengue infections are a significant cause of morbidity and mortality and lead to adverse social and economic impacts in many developing tropical countries. Dengue is a matter of much concern in India, where dengue is now re-emerging as one of the most important public health problems. Currently no vaccine has been licensed. The PlantVaccine project aims to develop a plant based vaccine candidate for dengue fever. This report reviews the status of and need for a dengue vaccine, easy accessibility and affordability, and overall social and economic implications of such a vaccine development in India.
Authors
Monica Hauger Carlsen Bente Lise Halvorsen Kari Holte Siv Kjølsrud Bøhn Steinar Dragland Laura Sampson Carol Willey Haruki Senoo Yuko Umezono Chiho Sanada Ingrid Elisabet Barikmo Nega Berhe Walter C Willett KM Phillips David Jacobs Rune BlomhoffAbstract
Conclusions: This database is to our best knowledge the most comprehensive Antioxidant Food Database published and it shows that plant-based foods introduce significantly more antioxidants into human diet than non-plant foods. Because of the large variations observed between otherwise comparable food samples the study emphasizes the importance of using a comprehensive database combined with a detailed system for food registration in clinical and epidemiological studies. The present antioxidant database is therefore an essential research tool to further elucidate the potential health effects of phytochemical antioxidants in diet.
Authors
Frank MillerAbstract
No abstract has been registered
Abstract
No abstract has been registered