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
Abstract
We examined the influence of fertigation on vegetative and generative parameters of strawberry plants (Fragaria × ananassa Duch.) and evaluated rapid analysing tools for N and K in leaf tissue. The experiments were undertaken in an open polytunnel on “table top” with ‘Sonata’ and ‘Korona’ grown in 2-L pots filled with a peat-based soil mixture. The experimental design was a randomized plot with three replications. Plants were fertigated with EC levels of 0.5, 1.0, 1.5 and 2.0 mS cm-1, based on two stock solutions of 7.5 kg YaraLiva™ Calcinit and 7.5 kg Kristalon™ Indigo, both dissolved in 100 L of water. Percentage N and K in leaves differed between analysing methods, cultivars, EC and date. We found interactions between the cultivar and EC level and between date and cultivar for N and K in leaf. Analysing NO3- by a photometric method (PM) in a lab, and by Laqua twin (LT), showed significant interaction with N% of leaf dry matter (DM) only for LT (r2=0.36). N% increased with higher EC level, more for ‘Korona’ than for ‘Sonata’. LT K+ did not correlate with K% (r2=0.014). The number of crowns and runners increased for both cultivars up to EC 1.5, while the number of leaves was unaffected. Petioles were the shortest at the lowest EC. Flower initiation was earlier at low EC in both cultivars. In the following spring, the time to flowering and first harvest was reduced with the decreasing EC. The number of flowers per plant increased up to EC 1.5, but dropped strongly at EC 2.0 for ‘Korona’, while ‘Sonata’ had a gradual increase of flowers with the increasing EC, but the number was only a third of ‘Korona’, except at EC 2.0, where the amount was equal for both cultivars. The conclusion can be drawn that LT correlated better than ChlDualex with N in strawberry leaves. However, r2 was only 0.36 indicating that LT NO3- is a coarse management tool. LT K+ was not a promising tool for rapid K+ test in these experiments. ‘Korona’ seemed to benefit of higher N levels for both vegetative growth and generative development than ‘Sonata’ up to EC 1.5, but ‘Sonata’ reached a higher floral primordia development stage in early October.
Authors
Mehreteab TesfaiAbstract
No abstract has been registered
Authors
Ngo Tien Dung Sekhar Udaya Nagothu Alma Linda Morales-Abubakar Jan Willem Ketelaar Mehreteab TesfaiAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Lunch canteens and their salad bars are an important arena for sales and consumption of vegetables including herbs. One major Norwegian canteen operator had a turnover of more than seven thousand tons of fresh vegetables in 2016, with lettuce, tomato, potato, cucumber and bell pepper being the most important species. A typical lunch meal included about 260 g vegetables including potatoes. Vegetables used in 450 canteens were either green, yellow, orange, red, purple/dark or colorless, and consisted of pigments of chlorophylls, carotenoids, anthocyanins and betalains. The total pigment content in the 60 most abundant vegetables was calculated to be 14.5-28.3 mg 100 g-1 FW. Of all vegetables in the canteens, 60% were found to be green. The intake of chlorophyll through one lunch meal was estimated to be 46 mg. Lettuce was found to be the single most important source of chlorophylls as this species was consumed in high amounts and made up 20% of the vegetables in a lunch meal. Carotenoids was found in all colored vegetables except the purple/dark ones and an estimate revealed an intake of 15 mg total carotenoids from lunch vegetables. Tomato was found to be the most important carotenoid source representing 44% of the total intake. Due to high pigment concentrations and popularity of red beets in the salad bars, the intake of betalains through a lunch meal was estimated to be 3 mg, similar to the total intake of anthocyanins from vegetable species.
Abstract
No abstract has been registered
Authors
Per-Erik Mellander Philip Jordan Marianne Bechmann Ophélie Fovet Mairead M. Shore Noeleen T. McDonald Chantal Gascuel-OdouxAbstract
Management of agricultural diffuse pollution to water remains a challenge and is influenced by the complex interactions of rainfall-runoff pathways, soil and nutrient management, agricultural landscape heterogeneity and biogeochemical cycling in receiving water bodies. Amplified cycles of weather can also influence nutrient loss to water although they are less considered in policy reviews. Here, we present the development of climate-chemical indicators of diffuse pollution in highly monitored catchments in Western Europe. Specifically, we investigated the influences and relationships between weather processes amplified by the North Atlantic Oscillation during a sharp upward trend (2010– 2016) and the patterns of diffuse nitrate and phosphorus pollution in rivers. On an annual scale, we found correlations between local catchment-scale nutrient concentrations in rivers and the influence of larger, oceanic-scale climate patterns defined by the intensity of the North Atlantic Oscillation. These influences were catchment-specific showing positive, negative or no correlation according to a typology. Upward trends in these decadal oscillations may override positive benefits of local management in some years or indicate greater benefits in other years. Developing integrated climatechemical indicators into catchment monitoring indicators will provide a new and important contribution to water quality management objectives.
Abstract
In cold climate regions a significant fraction of annual soil erosion in agricultural land occurs during snowmelt and rain on partially frozen soils. Physically based and spatially distributed soil erosion models have proved to be good tools for understanding the processes occurring at catchment scale during rainfall erosion. However, most existing erosion models do not account for snow in a suitable way. A combination of the UEBGrid snow pack model and the LISEM erosion model was therefore used in this study. The aim was to test and validate this model combination and to assess its utility in relation to quantification and process understanding. Applying this model combination to simulate surface runoff and soil erosion showed that, in principle, it is possible to satisfactorily simulate surface runoff and observed soil erosion patterns during winter. The values for the calibration parameters were similar for the two chosen winter periods when the rainfall and snowmelt episodes occurred. However, the calibration procedure showed that the utility of this combination had several limitations. It is hoped that this study can help to improve existing models and trigger new developments in including snow pack dynamics and soil freezing and thawing in soil erosion models.
Authors
Daniel Girma Mulat Janka Dibdiakova Mihaela Tanase Opedal Svein Jarle HornAbstract
No abstract has been registered