Hopp til hovedinnholdet

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

To document

Abstract

Deoxynivalenol (DON) in cereals, produced by Fusarium fungi, cause poisoning in humans and animals. Fusarium infections in cereals are favoured by humid conditions. Host species are susceptible mainly during the anthesis stage. Infections are also positively correlated with a regional history of Fusarium infections, frequent cereal production and non-tillage field management practices. Here, previously developed process-based models based on relative air humidity, rain and temperature conditions, Fusarium sporulation, host phenology and mycelium growth in host tissue were adapted and tested on oats. Model outputs were used to calculate risk indices. Statistical multivariate models, where independent variables were constructed from weather data, were also developed. Regressions of the risk indices obtained against DON concentrations in field experiments on oats in Sweden and Norway 2012–14 had coefficient of determination values (R2) between 0.84 and 0.88. Regressions of the same indices against DON concentrations in oat samples averaged for 11 × 11 km grids in farmers’ fields in Sweden 2012–14 resulted in R2 values between 0.27 and 0.41 for randomly selected grids and between 0.31 and 0.62 for grids with average DON concentration above 1000 μg kg–1 grain in the previous year. When data from all three years were evaluated together, a cross-validated statistical partial least squares model resulted in R2 = 0.70 and a standard error of cross-validation (SECV) = 522 μg kg–1 grain for the period 1 April–28 August in the construction of independent variables and R2 = 0.54 and SECV = 647 μg kg–1 grain for 1 April–23 June. Factors that were not accounted for in this study probably explain large parts of the variation in DON among samples and make further model development necessary before these models can be used practically. DON prediction in oats could potentially be improved by combining weather-based risk index outputs with agronomic factors.

To document

Abstract

Mountain tourism depends intensively on the quality of the landscape. In recent years, the Norwegian Trekking Association has focused on local food products at their staffed lodges and it uses the slogan “eat the view.” Such a strategy raises the focus on the agricultural use of the land and the quality of the products. Several Norwegian studies were carried out to investigate the quality of different mountain products and connections with vegetation types and grazing behavior. The results show that milk and meat products from animals grazing on alpine rangelands have improved quality compared to “normal” products. A healthier fatty acid composition and a higher content of secondary plant metabolites were characteristic of mountain products. Furthermore, grazing is of the utmost importance for the maintenance of open mountain landscapes and the biodiversity that is dependent on such landscapes. Maintaining traditional grazing systems also secures the preservation of traditional ecological knowledge about utilizing natural resources. Mountain tourism experiences could be improved and enhanced by documenting and telling the unique story of these complex connections between mountain landscapes, biodiversity, agricultural traditions, and local food products.

To document

Abstract

We conducted a series of diagnostic fitness response experiments on the coccolithophore, Emiliania huxleyi, isolated from the Subtropical Convergence east of New Zealand. Dose response curves (i.e., physiological rate vs. environmental driver) were constructed for growth, photosynthetic, and calcification rates of E. huxleyi relative to each of five environmental drivers (nitrate concentration, phosphate concentration, irradiance, temperature, and pCO2). The relative importance of each environmental driver on E. huxleyi rate processes was then ranked using a semi-quantitative approach by comparing the percentage change caused by each environmental driver on the measured physiological metrics under the projected conditions for the year 2100, relative to those for the present day, in the Subtropical Convergence. The results reveal that the projected future decrease in nitrate concentration (33%) played the most important role in controlling the growth, photosynthetic and calcification rates of E. huxleyi, whereas raising pCO2 to 75 Pa (750 ppm) decreased the calcification : photosynthesis ratios to the greatest degree. These findings reveal that other environmental drivers may be equally or more influential than CO2 in regulating the physiological responses of E. huxleyi, and provide new diagnostic information to better understand how this ecologically important species will respond to the projected future changes to multiple environmental drivers.

To document

Abstract

Phenological observations are considered to be sensitive tools for identifying plant responses to climatic changes. Over the last 10 years, the onset of the phenophases of sweet cherry (Prunus avium L.) during spring tended to be earlier than the previous two decades in Ullensvang, western Norway. The effects of air temperature during the winter and spring months were evaluated during two quinquennia (5-year periods), 1996-2000 (Q1) and 2003-2007 (Q2) selected due to similar mean winter and early summer temperatures, but markedly different spring temperatures. Average January-February temperatures were similar (3.3°C) in both of these two 5-year periods. However, average March and April temperatures were slightly warmer (4.0 vs. 3.2°C) and (7.3 vs. 6.9°C), respectively, in Q2 vs. Q1. These increases resulted in significantly earlier flower development. Average temperatures during the first half of May were similar for both quinquennia (10.2 vs. 10.1°C). The start of flowering (first bloom) of early maturing ‘Burlat’ and mid-season ‘Van’ were significantly different. Timing of flowering phenophases were statistically different between Q1 and Q2 for both cultivars. Mean data for ‘Burlat’ and ‘Van’ first bloom were 8 days earlier during Q2, May 2 for ‘Burlat’ and May 1 for ‘Van’. Full bloom occurred 3 days after first bloom and flowering ended 14 days after first bloom. First bloom during Q2 required 221 Baskerville-Emin Growing degree days (GDD) using a base temperature of 2°C. For the same time period in Q1, only 197 GDD were accumulated, which supports the observed temperature differences. Furthermore, we propose a flowering model for full bloom of both ‘Burlat’ and ‘Van’ in Ullensvang, which requires 254 Baskerville-Emin GDD using a base of 2°C starting on March 1.