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.
2020
Abstract
No abstract has been registered
Abstract
Farmers in Northern Norway frequently experience winter damaged fields caused by ice encasement. The economic consequences are severe due to loss of fodder and costs with reestablishment of swards. It is therefore important to choose the best available varieties for the local climatic and environmental conditions. We tested eight Norwegian cultivars of timothy (Phleum pratense), for tolerance to ice encasement and their regrowth capacity. Both old and new cultivars, and cultivars with good overwintering capacity and less biomass production were tested against more productive cultivars with less overwintering capacity. The experiment was a semi-field setup and plants were established in pots which were placed outside. Half of the pots were covered with ice and half were kept under snow cover. During four months, pots were brought, once per month, into a greenhouse for thawing and measurement of biomass production under normal growth conditions. The results indicate that the old winter hardy cultivar ‘Engmo’ is least affected by ice encasement but produces little biomass. The joint Nordic cultivar ‘Snorri’ produced most biomass of all the cultivars after a treatment with ice cover. In conclusion, there is a large difference between cultivars in ice encasement tolerance, and ice cover affected regrowth capacity far more than snow cover
Abstract
The main objective of this paper is to present the new model BASGRA_N, to show how it was parameterized for grass swards in Scandinavia, and to evaluate its performance in predicting above-ground biomass, crude protein, cell wall content and dry matter digestibility. The model was developed to allow simulation of: (1) the impact of N-supply on the plants and their environment, (2) the dynamics of greenhouse gas emissions from grasslands, (3) the dynamics of cell-wall content and digestibility of leaves and stems, which could not be simulated with its predecessor, the BASGRA-model. To calibrate and test the model, we used field experimental data. One dataset included observations of biomass (DM) and crude protein content (CP) under different N fertilizer regimes from five sites in central and southern Sweden. The other dataset included observations of DM, and sward components as well as CP, cell wall content (NDF) and DM digestibility as affected by harvesting regime from one site in southwestern Norway. The total number of experiments was nine, of which three were used for model testing. When BASGRA_N was run with the maximum a-posteriori (MAP) parameter vector from the Bayesian calibration for the Swedish test sites, DM and CP were both simulated to an overall Pearson correlation coefficient (Rb) of minimum 0.58, Willmott's index of agreement (d) of minimum 0.69 and normalized root mean squared error (NRMSE) of maximum 0.30. Corresponding metrics for Norwegian test sites were 0.93, 0.96 and 0.27 for DM and > 0.73, > 0.61, < 0.18 for DM digestibility, NDF and CP content, respectively. We conclude that BASGRA_N can be used to simulate yield and CP responses to N with satisfactory precision, while maintaining key features from its predecessor. The results also suggest that DM digestibility and NDF can be simulated satisfactorily, which is supported by results from a recent model comparison study. Further testing of the model is needed for a few variables for which we currently do not have enough data, notably leaching and emission of N-containing compounds. Further work will include application of the model to investigate greenhouse gas mitigation options, and evaluation against independent data for the conditions for which it will be applied.
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No abstract has been registered
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No abstract has been registered
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Organic amendments can improve grassland productivity. Timothy and tall fescue were sown on a sandy loam and a coarse sand at Særheim, Norway, in September 2016 and on a loamy sand at Skierniewice, Poland, in April 2017, and cut and fertilised according to normal practices for the two regions from 2017 to 2019. At both sites, 0.75 kg DM m-2 of either digested or undigested manure (the latter with or without 2.9 kg biochar m-2) were incorporated prior to sowing. On the coarse sand at Særheim, total seasonal tall fescue yield in 2018 was 46–60% higher in the organic amendment treatments, and total seasonal timothy yield in the digestate treatment was 97% higher, than in the control treatment for the same species with only mineral fertiliser. On the sandy loam at Særheim and the loamy sand at Skierniewice, none of the amendments resulted in significant yield increments. These results indicate a clear effect on soil type on grassland biomass response to organic amendments.
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No abstract has been registered
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No abstract has been registered
Authors
Vibeke Lind Martin Riis Weisbjerg Grete H. M. Jørgensen Julia E. Fernandez-Yepes Lesly Arbesú Eduarda Molina-AlcaideAbstract
The aim of the present work was to investigate the potential of Porphyra sp. as an alternative source of protein to soybean meal in diets for sheep. Our experimental treatments included a control diet (CON) based on grass silage and crushed oats and three diets containing protein supplements, clover silage (CLO), soybean meal (SOY) or Porphyra sp. (POR) to increase dietary crude protein concentrations. We studied its effects on rumen fermentation, growth rate and methane emissions. Ruminal fermentation characteristics, kinetics of gas production and methane production were studied in vitro by using batch cultures inoculated with rumen inoculum from sheep. There were no differences among diets in total volatile fatty acids (VFA) production or in the VFA profile in vitro. Across treatments, we measured no differences in methane production either in vitro or in vivo, and we saw no noticeable antimethanogenic effect of Porphyra sp. The present in vivo trial with lambs showed no differences in average daily weight gain when fed diets including Porphyra sp. or soybean meal diets (250 and 254 g/d, respectively). We conclude that Porphyra sp. has a protein value similar to high-quality protein sources like soybean meal.
Authors
Shelemia Nyamuryekung'e Andres F. Cibils Richard Estell Dawn VanLeeuwen Caitriana M. Steele Octavio Roacho Estrada Felipe A. Rodriguez Almeida Alfredo L. Gonzalez Sheri SpiegalAbstract
No abstract has been registered