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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.

2009

Sammendrag

The major objective of this study was to compile and examine empirical relationships between the driving forces and pressures that affect nitrogen cycling. Special attention was paid to riverine loads, fluxes, and concentrations of nitrogen in relation to agricultural factors (e.g., land use and fertilisers) at various spatial scales (plot, field, catchment, river basin, nation, region, continent, and world). Results of the present analyses and assessments reported in the literature indicate that at global, continental and inter-river basin scales, the level of riverine nitrogen loads (pressures) can be readily derived from simple empirical relationships with driving forces like population density and agricultural factors (e.g., proportion of arable land and fertiliser use). It seems that statistically derived relationships do not hold or are much weaker at the scales of single river basins and smaller catchments, whereas nitrogen losses appear to be correlated with fertiliser use at the smallest scales (plot and field). It is important to recognize this spatial nutrient paradox, particularly when such functional relationships are applied in the contexts of management and decision making. The implications for management are given further consideration in this paper.

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Sammendrag

Questions: Is the red fox a potential vector for epizoochorous seed dispersal? Can seed attachment and retention be predicted from plant and seed traits? Location: Grasslands in southern Norway.  Methods: Epizoochorous seed attachment on the red fox was studied by walking a dummy fox through the vegetation and comparing seeds found on the dummy with the estimated seed availability in the vegetation. Seed retention, i.e. the ability of different seeds to stay on the fox, was estimated in a separate experiment. Seed attachment and retention were related to plant and seed traits using statistical models that account for heteroscedasticity and zero-inflated data. Results: The majority of seeds attached to the fox originated from a few species, but also species without specific seed traits that are supposed to enhance epizoochory attached at least some seeds to the fox. The probability of seed attachment was positively related to plant height, bristle and hooked seed appendages, and negatively related to winged appendages, seed mass, and seed sphericity. Seed retention was positively related to theseed traits bristles, hooks and pappus. For several species, the results indicate a high potential for dispersal over long distances. Conclusions: In modern agricultural landscapes, large herbivores are often restricted in their mobility or are found at low densities, and other animal vectors may therefore be important for seed dispersal. In our study, a range of plant species were able to disperse by attaching seeds to, and having their seeds retained in, the fox fur some distance. We suggest that the red fox may be an important vector for epizoochorous seed dispersal in the agricultural landscape.

Sammendrag

As part of a project on cultivation and industrial exploitation of European Blueberry (Vaccinium myrtillus ) started in 2008, berries from different wild populations from South, Mid and North Norway were investigated. One aspect of fruit quality analyses was to identify and describe blueberry aroma profiles. Volatiles were extracted by headspace solid-phase microextraction (HS-SPME) and analysed by gas chromatography/ mass spectrometry (GC/MS) (Rohloff, 2004). More than 100 compounds could be identified based on MS database search and retention indices, also comprising aroma impact compounds not being described in blueberries earlier (Sydow & Anjou, 1969). Detected aliphatic and aromatic structures belonged to chemical groups such as alkanes, acids, alcohols, aldehydes, esters, ketones and mono- and sesquiterpenes. Ten major compounds (mostly C4-, C6- and C9-structures) accounted for averagely 65-75 % relative amount of all detected peaks. However, HS-SPME analyses revealed complex volatile profiles including terpenes (>20 compounds, e.g. p-cymene, 1,8-cineole, linalool) and aromatic structures (>10 compounds, e.g. benzaldehyde, ethyl benzoate, 2-phenylethyl acetate, benzyl benzoate), which contribute to the characteristic and flavourful blueberry aroma.

Sammendrag

Wild berries are characteristic part of the Northern nature and a potential speciality of Nordic countries. Wild berries are also a rich and valuable resource that has not yet been exploited in a satisfactory level. Approximately 90-95 per cent of the whole wild berry crop yield is left unpicked in the Nordic forests every year. The challenges of the wild berry utilization are similar in Nordic countries - the logistics of berry picking including traceability, fragmented sector structure as well as the high share of unprocessed raw material in export. The Nordic project focusing on bilberry (Vaccinium myrtillus) "Bilberry: Towards functional food markets" (2007-2009) is a part of the New Nordic Food programme funded by the Nordic Innovation Centre. The programme aims to enhance cooperation and innovation among companies that utilize the natural resources in the Nordic countries. The aim of the project is to improve wild berry production and utilization in the Nordic and global market. To achieve this goal a network between the Nordic experts presenting the different fields of the wild berry sector has been established. The project has focused on marketing research, quality issues, biodiversity and traceability of wild berries, especially bilberry. The results of the marketing survey were published in November 2008. The aim of the survey was to generate an overall picture of the companies working with wild berries in Nordic countries and gather information on the existence and willingness of the berry companies to cooperate for instance in wild berry supply, logistics, marketing or research and development. According to the results, a general agreement for the need of increased cooperation at the Nordic level was highlighted

Sammendrag

Bilberry (Vaccinium myrtillus), also called European blueberry, is one of the most significant wild berries in the Nordic countries. The berries are recognized for their bioactive properties and distinctive aroma and flavour. The effects of climate on production and the quality of bilberries have been studied in a controlled experiment in a phytotrone using clonal material. In the experiment individual plants from two Northern clones and two Southern clones of bilberry have been grown at 12° and 18°C. At each temperature 2 different light treatments have been tested; 1) 24 hour (h) natural light (long day) and 2) 12 h natural light (short day). All plants were kept outside during flowering to ensure pollination by insects. Berries were sampled when ripe, weighed and stored at -80°C for later analysis

Sammendrag

Two female and two male cultivars have previously been released as a result of clone evaluation at Bioforsk Nord Holt. Selection criteria have been number of pistils or stamens per flower, number of flowers and number of shoots per m2. Currently a new group of clones are evaluated with the aim of finding new cultivars for release. Preliminary results on flowering and berry production show strong variance in these traits. Over three years of registration, number of produced flowers varied from under 100 for the weakest clone to more than 1000 for the best clone. Number of produced berries varied from 9 for the weakest clone to 242 for the best clone. The three clones that produced most flowers all had very low berry production and deviated from the rest of the clones by having high numbers of flowers per harvested berry. New selection criteria will be considered before selection of new cultivars for release.