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.
2023
Forfattere
Marcos Viejo Torstein Tengs Igor A. Yakovlev Hugh Cross Paal Krokene Jorunn Elisabeth Olsen Carl Gunnar FossdalSammendrag
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Forfattere
Tatiana Francischinelli Rittl Teresa Gómez de la Bárcena Eva Farkas Trond Henriksen Sigrid Trier Kjær Peter Dörsch Randi Berland FrøsethSammendrag
In Norway, cover crops were introduced to prevent loss of nitrogen and phosphorous from fields to waterways. Today, cover crops are also used to restore soil organic matter and improve soil health. Yet, the direction and magnitude of these effects are variable, and little is known about the persistence of the C derived from the cover crops in the soil. In the CAPTURE project, we evaluated the soil C sequestration potential from different cover crops used in the main cereal production areas in Norway. To do so, we used pulse labelling with 13C (CO2) to label four different cover crop species Italian ryegrass, phacelia, oilseed radish and summer vetch through their growing period. Cover crops were grown in a monoculture to enable the labelling. The results of the first year of the experiment show that cover crops produced 10- 14 Mg ha-1 above ground biomass, corresponding to 4-6 Mg C ha-1. At the end of the growing season, 3-5% of cover crop C was found in the soil particulate organic matter (POM) fraction and 2-4% in the soil mineral organic matter fraction (MAOM). In the following years, the fate of C derived from the cover crops in the soil will be determined. Furthermore, the soil C sequestration of the different cover crops will be scaled to barley plots in the same experiment, to which cover crops had been undersown in spring or summer. In these plots, N2O emissions have been measured through the whole year. The greenhouse gas trade-offs of cover crops in Norwegian cereal production will be estimated.
Forfattere
Qiang Liu Yuanting Xu Yeqing Li Chengjie Ma Shuo Chen Lu Feng Quan Xu Junting Pan Bo Peng Hongjun Zhou Chunming XuSammendrag
Monophenols form humic acids (HA) through polycondensation reaction in the anaerobic digestion (AD) process, which will inhibit AD process. Currently, metal ions are the option for in-situ relieving HA inhibition during AD, but excess metal ions are harmful to microorganisms. In this study, carbon quantum dots (CQDs, a non-metallic materials) were proposed to relieve HA inhibition in-situ. We investigated the effect of HA on AD acidification and methanation stage, and synthesized CQDs using sodium citrate (s-CQDs) and p-phenylenediamine (p-CQDs) as precursors to relieve the HA inhibition in-situ. Results showed that s-CQDs (3.0 g/L) significantly increased the cumulative CH4 yield from AD of ethanol with 1.0 g/L HA (1.9 times higher than that without s-CQDs). Microbiological analysis indicated the most dominant methanogen was Methanosarcinaceae, with richness of 89.7%. Compared to the HA inhibition system, the relative abundance of Methanosarcinaceae increased by 87.5%. The analysis of interaction mechanism between CQDs and HA indicated that s-CQDs has an in-situ binding effect to HA by reacting with -OH, Cdouble bondC, and -COOH. This study provided a novel means for in-situ relieving HA inhibition, and illustrated the interaction mechanism between CQDs and HA, which will guide the application in production of bioenergy.
Forfattere
Habtamu AlemSammendrag
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Forfattere
Christian Oliver Ewald Jelena Hadina Erik Haugom Gudbrand Lien Ståle Størdal Muhammad YahyaSammendrag
In this paper we examine how sensitive Value-at-Risk (VaR) forecasts based on simple linear quantile regressions are to the sampling frequency used to calculate realized volatility. We use sampling frequencies from one to 108 min for ICE Brent Crude Oil futures and test the out-of-sample performance of a set of quantile regression models using formal coverage tests. The results show that a one-factor model performs exceptionally well for most sampling frequencies used to calculate realized volatility. In comparison with the well-known Heterogeneous Auto-regressive Model of Realized Volatility (HAR-RV) and a quantile regression version of the HAR model (HAR-QREG), we also find that the one-factor model is much less sensitive to the sampling frequency used to calculate realized volatility.
Forfattere
Sunniva Løwø Simeon Rossmann Marte Persdatter Tangvik Monica Skogen Solveig Haukeland Ulrike Naumann May Bente BrurbergSammendrag
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Sammendrag
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Sammendrag
The SiEUGreen project was implemented to enhance the EU-China cooperation in promoting urban agriculture (UA) for food security, resource efficiency and smart, resilient cities through the development of showcases in selected European and Chinese urban and peri-urban areas. In the last four years, SiEUGreen project assembled numerous existing and/or unexploited technologies for the first time to facilitate the development of the state-of-the-art UA model. In light of this, there is natural interest in whether SiEUGreen’s efforts resulted in meaningful impacts. Hence, the objective of this report is to determine the multi-dimensional impacts of the showcases developed and implemented by the SiEUGreen project. The analysis of the impact of the technologies or showcases implemented by the SIEUGreen mainly relies on the data obtained from other relevant tasks and deliverables within the project (e.g., showcase deployment, market analysis, and deliverables related to technology deployment). The willingness to pay studies use NIBIO’s existing data from a contingent valuation survey for willingness to pay of Oslo residents towards food produced using the target technologies. The report is presented as follows: • Section 2 gives an overview of the implementation status of the SiEUGreen technologies with the current technology readiness levels (TRLs); • Section 3 discusses the impacts in terms of land use, food security, environmental resilience and resource efficiency, and societal inclusion; • Section 4 focuses on willingness to pay studies for UA-related technologies; • Section 5 discusses the results and impact pathways; and • Section 6 provides the lessons learned and recommendations. Overall, our assessment indicates that SiEUGreen has provided a wide-ranging array of impacts in multiple dimensions: land-use, food security, environmental resilience and resource efficiency, and societal inclusion.
Forfattere
Stephanie Saussure Annette Bruun Jensen Marie Louise Davey Annette Folkedal Schjøll Karin Westrum Ingeborg KlingenSammendrag
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Sammendrag
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