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.
2017
Authors
Tomasz Leszek Woznicki Anita Sønsteby Kjersti Aaby Berit Karoline Martinsen Ola M. Heide Anne-Berit Wold Siv Fagertun RembergAbstract
BACKGROUND Marked effects of the climatic environment on fruit chemical composition have often been demonstrated in field experiments. However, complex covariations of several climatic factors in the natural environment complicate the interpretation of such experiments and the identification of the causal factors. This can be better achieved in a phytotron where the various climatic factors can be varied systematically. Therefore, we grew four black currant cultivars of contrasting origin in a phytotron under controlled post-flowering temperature and photoperiod conditions and analysed the berries for their ascorbic acid, sugar and organic acid contents. RESULTS The analyses revealed significant effects of genotype on all investigated compounds. Particularly large cultivar differences were observed in the concentrations of l-ascorbic acid (AA) and sucrose. The concentrations of both AA and dehydroascorbic acid (DHAA), as well as the concentrations of all major sugars, decreased consistently with an increasing temperature over the temperature range 12–24 °C. Fructose and glucose were the predominant sugars with concentrations several fold higher than that for sucrose. AA was the main contributor to the total ascorbate pool in black currant berries. The AA/DHAA ratio varied from 5.6 to 10.3 among the studied cultivars. The concentration of citric acid, which was the predominant organic acid in black currant berries, increased with an increasing temperature, whereas the opposite trend was observed for malic and shikimic acid. Quninic acid was always present at relatively low concentrations. By contrast, photoperiod had no significant effect on berry content of any of the investigated compounds. CONCLUSION It is concluded that the post-flowering temperature has marked effects on the concentration of important chemical compounds responsible for taste and nutritional value of black currant berries, whereas photoperiod has no such effect in the studied cultivars. © 2016 Society of Chemical Industry
Abstract
No abstract has been registered
Abstract
Source at <a href=https://doi.org/10.1371/journal.pone.0170582> https://doi.org/10.1371/journal.pone.0170582 </a>
Authors
Lorenzo Marini Bjørn Økland Anna Maria Jönsson Barbara Bentz Allan Carroll Beat Forster Jean-Claude Grégoire Rainer Hurling Louis Michel Nageleisen Sigrid Netherer Hans Peter Ravn Aaron Weed Martin SchroederAbstract
Bark beetles are among the most devastating biotic agents affecting forests globally and several species are expected to be favored by climate change. Given the potential interactions of insect outbreaks with other biotic and abiotic disturbances, and the potentially strong impact of changing disturbance regimes on forest resources, investigating climatic drivers of destructive bark beetle outbreaks is of paramount importance. We analyzed 17 time-series of the amount of wood damaged by Ips typographus, the most destructive pest of Norway spruce forests, collected across 8 European countries in the last three decades. We aimed to quantify the relative importance of key climate drivers in explaining timber loss dynamics, also testing for possible synergistic effects. Local outbreaks shared the same drivers, including increasing summer rainfall deficit and warm temperatures. Large availability of storm-felled trees in the previous year was also strongly related to an increase in timber loss, likely by providing an alternative source of breeding material. We did not find any positive synergy among outbreak drivers. On the contrary, the occurrence of large storms reduced the positive effect of warming temperatures and rainfall deficit. The large surplus of breeding material likely boosted I. typographus population size above the density threshold required to colonize and kill healthy trees irrespective of other climate triggers. Importantly, we found strong negative density dependence in I. typographus that may provide a mechanism for population decline after population eruptions. Generality in the effects of complex climatic events across different geographical areas suggests that the large-scale drivers can be used as early warning indicators of increasing local outbreak probability.
Authors
Tatjana Kince Ruta Galoburda Dace Klava Lolita Tomsone Santa Senhofa Evita Straumite Garry Kerch Arta Kronberga Ievina Sturite Daiga Kunkulberga Anita BlijaAbstract
The aim of the study was to investigate changes of physical, microbiological, and sensory properties of muesli with germinated fakes during storage. Germinated fakes were made from conventionally grown grains: hullless barley, hull-less oat, rye, wheat, and triticale in various proportions. Breakfast cereals samples were packaged in Doypack (stand up pouches) made from Pap50g/Alu7/ Pe60 (Pap/Alu/PE) and stand up pouches Fibrecote® HB MG 40/60 (PE/EvOH/Pap) and stored for 6 months at temperature t=35±2°C and relative air humidity φ=55±3%, to provide accelerated shelf-life testing. The main quality parameters such as total plate count, yeasts and mould, water activity, moisture content, water absorption and sensory properties—taste, aroma, consistency, and appearance were analysed using the standard methods. The results of the present experiments demonstrate that the best quality of dried breakfast cereals after storage in terms of sensory quality, microbiological stability, moisture migration, and water absorption were achieved in the Fibrecote® HB MG 40/60 pouches. This study revealed that breakfast cereals made from rye, triticale germinated triticale, germinated hull-less oat, germinated hull-less barley fakes; as well breakfast cereals made from triticale, oat, germinated wheat, germinated triticale, and germinated hull-less barley fakes packaged in Fibrecote® HB MG 40/60 can be stored for 12 months at temperature 23±2°C; but breakfast cereals made from wheat, rye, triticale, germinated hull-less oat, germinated hull-less barley, germinated rye fakes and package in same packaging material can be stored for 10 months at temperature 23±2°C.
Abstract
This work focuses on modelling soil water reserves using an Artificial Neural Net-work (ANN). Four model variants were established based on 843 records (verifiedthrough 268 measurements) of soil water content (SWC) measured at full-scale fieldsites located in Southwest Poland. It is revealed that commonly recorded climaticdata (precipitation and temperature) linked with SWC and field water capacity(FWC) are applicable in the ANN modelling. The basic model (utilising the meteoro-logical data) was the most suitable for soil profiles with thicknesses of 0–25 cm,while in profiles with thicknesses of 0–50 cm and 0–100 cm the comprehensiveANN model (linking climatic data, FWC and SWC) was the most appropriate. Fur-thermore, comparative studies of the measured and modelled data indicated theirstatistical convergence, thus providing support for the practical implementation ofthe proposed ANN modelling.
Abstract
No abstract has been registered
Abstract
Field trials of Abies lasiocarpa were undertaken with the aim of assessing the potential for Christmas tree production in Denmark. Twenty-six provenances originating from Alaska to New Mexico were tested. Damage by the insect Adelges piceae and the fungus Neonectria neomacrospora was recorded for the first time 8 and 12 years after the initial planting. Damage from N. neomacrospora increased rapidly in the period 12–15 years after planting. Trees from the northern provenances and humid climates exhibited less damage than those from southern ones. Previous attack by A. piceae had a minor effect on N. neomacrospora infection. Greenhouse tests showed that detached shoots from healthy Abies lasiocarpa can be used to rank provenances for resistance to N. neomacrospora, but results varied according to host subspecies.
Authors
Jussi Vuorenmaa Algirdas Augustaitis Burkhard Beudert Nicholas Clarke Heleen de Wit Thomas Dirnböck Jane Frey Martin Forsius Iveta Indriksone Sirpa Kleemola Johannes Kobler Pavel Kram Antti-Jussi Lindroos Lars Lundin Tuija Ruoho-Airola Liisa Ukonmaanaho Milan VánaAbstract
Empirical evidence based on integrated environmental monitoring including physical, chemical and biological variables is essential for evaluating the ecosystem benefits of costly emission reduction policies. The international multidisciplinary ICP IM (International Cooperative Programme on Integrated Monitoring of Air Pollution Effects on Ecosystems) programme studies the integrated effects of air pollution and climate change on ecosystems in unmanaged and calibrated forested catchments. We calculated site-specific annual input-output budgets for sulphate (SO4) and total inorganic nitrogen (TIN NO3- N + NH4-N) for 17 European ICP IM sites in 1990–2012. Temporal trends for input (deposition) and output (runoff water) fluxes and the net retention/net release of SO4 and TIN were also analysed. Large differences in the input and output fluxes of SO4 and TIN reflect important gradients of air pollution effects in Europe, with the highest deposition and runoff water fluxes at IM sites located in southern Scandinavia and in parts of Central and Eastern Europe and the lowest fluxes at more remote sites in northern European regions. A significant decrease in the total (wet + dry) deposition of non-marine SO4 and bulk deposition of TIN was found at 90% and 65% of the sites, respectively. Output fluxes of non-marine SO4 in runoff decreased significantly at 65% of the sites, indicating positive effects of the international emission abatement actions in Europe during the last 20 years. Catchments retained SO4 in the early and mid1990s, but this shifted towards a net release in the late 1990s, which may be due to the mobilization of legacy S pools accumulated during times of high atmospheric SO4 deposition. Despite decreased deposition, TIN output fluxes and retention rates showed a mixed response with both decreasing (9 sites) and increasing (8 sites) trend slopes, and trends were rarely significant. In general, TIN was strongly retained in the catchments not affected by natural disturbances. The long-term annual variation in net releases for SO4 was explained by variations in runoff and SO4 concentrations in deposition, while a variation in TIN concentrations in runoff was mostly associated with a variation of the TIN retention rate in catchments. The net release of SO4 from forest soils may delay the recovery from acidification for surface waters and the continued enrichment of nitrogen in catchment soils poses a threat to terrestrial biodiversity and may ultimately lead to a higher TIN runoff through N-saturation. Continued monitoring and further evaluations of mass balance budgets are thus needed.
Authors
Laurens Klerkx Egil Petter Stræte Gunn-Turid Kvam Eystein Ystad Renate Marie Butli HårstadAbstract
No abstract has been registered