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
This article focus is on the perceived impact that aquaculture industry has on coastal communities in Northern Norway. Here, aquaculture is key industry with natural, social and economic impacts. In natural resource management in general, identifying and monitoring the perceived social impacts can be a useful tool for local planning. In order to ensure the blue growth goals of the Norwegian government and avoid conflict and mistrust in the future, it is important to understand how both the general public and stakeholders perceive the aquaculture industry, how it affects them and its use of space in the coastal zone. Hence, we ask a) how do coastal communities perceive the aquaculture industry and b) is there a legitimacy gap between the blue growth strategies of the Norwegian Government and the public? In order to answer these questions, we lean on theories related to legitimacy and stakeholder's participation. Original data were collected from structured (N = 150) and semi-structured interviews (N = 10) in two coastal communities in Northern Norway (Alstahaug and Brønnøy). Our findings suggest that a legitimacy gap does exist between blue growth goals and fishers in the communities studied, while the general citizen holds a positive attitude towards aquaculture. Insights from this study are useful for local, regional and national decision makers with responsibility for natural resource policies and development efforts.
Abstract
Microbes are central drivers of soil processes and in-depth knowledge on how agricultural management practices effects the soil microbiome is essential in the development of sustainable food production systems. Our objective was therefore to explore the long-term effects of organic and conventional cropping systems on soil bacterial and fungal quantity, their community structures and their combined function. To do so, we sampled soil from a long-term experiment in Southeast Norway in 2014, 25 years after the experiment was established, and performed a range of microbial analyses on the samples. The experiment consists of six cropping systems with differences in crop rotations, soil tillage, and with nutrient application regimes covering inorganic fertilizers, cattle slurry (both separately and combined with inorganic fertilizers) and biogas residues from digested household biowaste. The quantity of soil microbes was assessed by extraction of microbial C and N and by analysis of soil DNA (bacterial 16S rRNA, and fungal rRNA internal transcribed spacer region). The structures of the microbial communities were determined and assessment of relatedness of bacterial and fungal communities was done by the unweighted pair group method. Estimates of richness and diversity were based on numbers of unique operational taxonomic units from DNA sequencing and the function of the microbial assembly was measured by means of enzyme assays. Our results showed that production systems including leys had higher microbial biomass and higher numbers of bacterial and fungal gene copies than did systems with cash crops only. A cropping system which appeared to be particularly unfavourable was a reference-system where stubble, roots and exudates were the single source of organic material. Production system significantly affected both bacterial and fungal community structures in the soil. Systems including leys and organic fertilization had higher enzyme activities than did systems with cash crops only. An inclusion of ley in the rotation did not, however, increase either microbial richness or microbial diversity. In fact, the otherwise suboptimal reference-system appeared to have a richness and diversity of both bacteria and fungi at levels similar to those of the other cropping systems, indicating that the microbial function is largely maintained under less favourable agricultural treatments because of the general resilience of soil microorganisms to various stresses. Neither disturbance through tillage nor the use of chemical fertilizer or chemical plant protection measures seemed as such to influence soil microbial communities. Thus, no differences between conventional and organic farming practices as such were found. We conclude that the choice of agricultural management determines the actual microbial community structure, but that biodiversity in general is almost unaffected by cropping system over many years. Adequate addition of organic material is essential to ensure a properly functioning microbial ensemble and, thus, to secure soil structure and fertility over time.
Abstract
The study aimed to explore whether an increase in bunker silage density obtained by turning to a heavier packing machine than a farm size tractor would reduce losses and improve grass silage quality and aerobic stability. At each of three harvests, two bunkers were packed with either a 14.5 t wheel loader (WL) or an 8.3 t tractor (T). For comparison with the bunker silages, silage was produced simultaneously in round bales with high and low chamber pressure and wrapped immediately or after delay, and in laboratory silos. Compaction with WL increased silage dry matter (DM) density by 9 % compared with T, from 204 to 222 kg DM/m3. On average for three harvests, DM recovered as silage, or lost, was almost identical for the two packing treatments, with 870 g/kg of harvested DM recovered as feed offered to animals, 55 g/kg as wasted silage, and 75 g/kg as invisible losses due to respiration, effluent, fermentation and aerobic deterioration. However, in the harvest with lowest crop DM content, 266 g/kg, invisible DM losses with WL exceeded losses with T by 46 g/kg, of which the main portion was assumed to be caused by more effluent squeezed out by the WL. In the harvest with highest crop DM, 332 g/kg, invisible DM losses with T exceeded losses with WL by 43 g/kg, of which the main portion was assumed to be caused by poorer compaction with T, and therefore higher respiration and aerobic deterioration losses. Wasted silage DM was lower in bales than in bunkers (P = 0.004). The proportion of offered silage DM from poorly compacted bales sealed after delay (867 g/kg) was similar to that of bunkers, whereas the proportion of offered silage DM from well compacted and immediately sealed bales (963 g/kg) was similar to that of laboratory silos. Significant increases in protein bound in the neutral detergent and acid detergent fiber fractions were found in bales sealed after delay where temperatures had rised to 47 °C at wrapping. Similar levels of fiber bound protein were found in bunker silage, suggesting that they were also heated during filling. Spot samples from bunker silo shoulders were more infected by yeasts, moulds and Clostridium tyrobutyricum than samples from mid in bunkers and from bales. No differences in losses, silage composition or aerobic stability were observed between bunker silo packing with WL or T on average over three harvests.
Abstract
No abstract has been registered
Authors
Barbara Łaska-Zieja Damian Marcinkowski Wojciech Golimowski Gniewko Niedbała Ewelina WojciechowskaAbstract
Rapeseed oils are a valuable component of the diet. Mostly, there are refined oils deprived of valuable nutrients in the market, hence in recent times cold-pressed and unrefined oils have been available and popular among consumers. However, the low yield of this oil makes this product expensive. The aim of the study was to analyse the effectiveness of phosphorus reduction in crude oils, cold- and hot-pressed in the low-temperature bleaching process. Eight market-available bleaching earths was compared. The effectiveness of 90% was found with 2% (m/m) of Kerolite with hydrated magnesium silicate. An increase in the share of earths to 4% (m/m) resulted in the effectiveness of phosphorus reduction >90% in seven out of eight analysed cases. Bentonite activated with acid with the lowest MgO content was characterised by low efficiency <64%. The research shows that the effectiveness of phosphorus reduction was significantly affected by the composition of earths applied in the bleaching process at ambient temperature. The results of research confirm the high effectiveness of the process as it is not necessary to heat up the oil before the bleaching process. This method is recommended for existing and new industrial plant for two-stage rapeseed oil pressing.
Authors
Gunnhild SøgaardAbstract
No abstract has been registered
Abstract
The rapidly expanding field of machine learning (ML) provides many methodological opportunities which match very well with the needs and challenges of hydrological research. Due to extended measurement networks, more frequent automatic measurements of hydrological variables, and not the least increasing use of remote sensing products, the era of big data surely has arrived in hydrology. Process-based models are usually developed for certain spatiotemporal scales, not fitting easily to the scope of the new datasets. Automatic methods that learn patterns and generalizations have been demonstrated to be superior in many applications. The chapter provides an overview of some of the most important machine learning algorithms which have been used in the hydrological literature. It will be shown that there is no single best method among them, but instead a spectrum of methods should be utilized, from highly flexible ones to more parsimonious learning methods, depending on the specific hydrological application, research question, and data availability. Most machine learning techniques require a calibration and a validation dataset for training. As these data are usually correlated in time and space, the problem of bias-variance tradeoff arises will be discussed as a simple example. The presentation of ML algorithms, roughly following chronological order, is discussed starting with artificial neural networks through support vector machines to gradient boosting machines. As data streams increase, these and other machine learning techniques will play an ever more important role in hydrology.
Abstract
No abstract has been registered
Abstract
There is a need for new solutions in wood protection against marine wood borers and termites in Europe. A new solution could be the esterification of wood with sorbitol and citric acid (SCA) since these are inexpensive and readily available feedstock chemicals and have shown protective properties against fungal wood degradation in earlier studies and prevented macrobiological degradation, as shown in this study. Protection of wood products in the marine environment lacks available wood preservatives that are approved for marine applications. Termite infestation is opposed mainly by biocide treatments of wood. Several wood modification systems show high resistance against both marine borers and subterranean termites. However, the existing commercialized wood modification products are costly. Both macrobiological forms of degradation represent a great threat for most European wood species, which are rapidly and severely degraded if not properly treated. This study investigated esterified wood in standard field trials against marine wood borers, and against subterranean termites in laboratory trials in a no-choice and choice test. The treatment showed good resistance against wood borers in the marine environment after one season and against subterranean termites in the laboratory after eight weeks. The low termite survival rate (SR) in the no-choice test during the first week of testing indicates a mode of action that is incomparable to other wood modification treatments.