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.
2020
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Perennial versus short term (<3 years) grass vegetation cover is likely to have considerable differences in root density and thus carbon (C) inputs to soil. Carbon inputs are important to maintain soil organic carbon (SOC) and may even increase it. In Norway and Scandinavia, the SOC content in soil is often higher than in other parts of Europe, due to the cold climate and high precipitation (i.e. slower turnover rates for soil organic matter) and a dominance of animal production systems with a large amount of grassland. Here we aimed to evaluate differences in SOC content, down to 60 cm depth, of a long-term grassland (without ploughing for decades) and a short-term grassland (frequently renewed by ploughing) under contrasting climate, soil and management conditions. Quantification of SOC was carried out on three long-term experimental sites on an extended latitude gradient in West and North Norway. The samples were taken from 4 depth increments (0-5, 5-20, 20-40 and 40-60 cm) in treatments that have not been ploughed for at least 43 years, and in treatments that were ploughed every third year until 2011. Preliminary results suggest that there is no significant difference in SOC storage down to 60 cm between long-term and short-term grasslands.
Forfattere
Shelemia Nyamuryekung'e Andres F. Cibils Richard Estell Dawn VanLeeuwen Caitriana M. Steele Octavio Roacho Estrada Felipe A. Rodriguez Almeida Alfredo L. Gonzalez Sheri SpiegalSammendrag
Det er ikke registrert sammendrag
Sammendrag
Several scientific groups have concluded that the use of biochar as an on-farm management tool for carbon sequestration should be further investigated. Review articles also pinpoint the use of biochar to reduce greenhouse gas emissions from the entire agricultural production, and this should be studied using whole-chain models. Biochar is added to animal diets with the main purpose of enhancing animal health. There are indications that biochar fed to ruminants may reduce enteric methane emission. Twenty-four ewe lambs were fed one of two diets, a control diet (no biochar) and a biochar diet (1.4% biochar). There were no differences in dry matter intake and average daily growth rate between animals. An expected reduction in enteric methane emissions from animals fed the biochar diet was not detected. We conclude that the effect on enteric methane emissions may depend on structure and properties of the biochar offered. We suggest further research on biomass and pyrolysis of biochar to accommodate several properties as a feed additive for farm animals.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Ralf RautenbergerSammendrag
The commercial cultivation of marine macroalgae is a young and rapidly growing industry sector in Norway. Although it is currently limited to a few brown macroalgae, other species such as the green marine macroalga Ulva fenestrata (formerly Ulva lactuca) has also a high potential for an industrial biomass production, for example to be used for the food marked. However, this process is strongly affected by the presence of marine diatoms transported along with the seawater into the cultivation system of U. fenestrata. These diatoms not only proliferate in the water tanks, they also colonise the green macroalgal biomass with many brown spots, which reduces its value for the food marked significantly. This presentation shows the results of a project that studied the use of germanium dioxide (GeO2) as a known growth inhibitor of diatoms to control their contamination during the biomass production process of U. fenestrata. First, the co-occurring diatom was morphologically identified as Fragilaria sp. using light microscopy. Thereafter, a dose-response experiment was conducted to reveal the concentrations of GeO2, resulting in an effective growth inhibition of Fragilaria sp. Based on this knowledge, the impact of different GeO2 concentrations was studied on how the photophysiolgy (photosynthetic characteristics, pigment patterns) and growth of U. fenestrata are affected in both small-scale (2 L) and large-scale (100 L) cultivation systems. An effective control of the proliferation of Fragilaria sp. during the cultivation process of U. fenestrata may result in the production a high-quality biomass with a high value for the food marked.
Forfattere
Serena Lima Peter Simon Claus Schulze Lisa M. Schüler Ralf Rautenberger Daniela Morales-Sanchez Tamára F. Santos Hugo Pereira João C.S. Varela Francesca Scargiali Rene Hubertus Wijffels Viswanath KironSammendrag
As the periodic emission of light pulses by light emitting diodes (LEDs) is known to stimulate growth or induce high value biocompounds in microalgae, this flashing light regime was tested on growth and biochemical composition of the microalgae Nannochloropsis gaditana, Koliella antarctica and Tetraselmis chui. At low flashing light frequencies (e.g., 5 and 50 Hz, Duty cycle = 0.05), a strain-dependent growth inhibition and an accumulation of protein, polyunsaturated fatty acids, chlorophyll or carotenoids (lutein, β-carotene, violaxanthin and neoxanthin) was observed. In addition, a 4-day application of low-frequency flashing light to concentrated cultures increased productivities of eicosapentaenoic acid (EPA) and specific carotenoids up to three-fold compared to continuous or high frequency flashing light (500 Hz, Duty cycle = 0.05). Therefore, applying low-frequency flashing light as finishing step in industrial production can increase protein, polyunsaturated fatty acids or pigment contents in biomass, leading to high-value algal products.
Forfattere
Magda Chudzinska Yoko L. Dupont Jacob Nabe-Nielsen Kate P. Maia Marie Vestergaard Henriksen Claus Rasmussen W. Daniel Kissling Melanie Hagen Kristian TrøjelsgaardSammendrag
Understanding interactions between individual animals and their resources is fundamental to ecology. Agent-Based Models (ABMs) offer an opportunity to study how individuals move given the spatial distribution and characteristics of their resources. When contrasted with empirical individual-resource network data, ABMs can be a powerful method to detect the processes behind observed movement patterns, as they allow for a complete and quantitative analysis of the agent-to-environment relationships. Here we use the small-scale, within-patch movement of bumblebees (Bombus pascuorum) as a case study to demonstrate how ABMs can be combined with network statistics to provide a deeper understanding of the mechanisms behind the interactions between individuals and their resources. We build an ABM that explicitly simulates the influence of distance to the nearest flowering plant (allowing minimal energy expenditure and maximum time spent foraging), plant height and number of flower heads (as a proxy of food availability) on local foraging decisions of bumblebees. The relative importance of these three elements is determined using pattern-oriented modelling (POM), where we confront the network statistics (number of visited plants, number of interactions, nestedness and modularity) of a real B. pascuorum individual-resource network with the emergent patterns of our ABM. We also explore the model results using spatial analysis. The model is able to reproduce the observed network statistics. Despite the complex behaviour of bumblebees, our results show a surprisingly precise match between the structure of the simulated and empirical networks after adjusting a single model parameter controlling the importance of distance to the next plant visited. Our study illustrates the potential of combining field data, ABMs and individual-resource networks for evaluating small-scale, within-patch movement decisions to better understand animal movements in natural habitats. We discuss the benefits of our approach when compared to more classical statistical methods, and its ability to test various scenarios in a new or altered environment.
Forfattere
Marie Vestergaard HenriksenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Rapporten beskriver og dokumenterer inntektsvariasjon mellom ulike grupper gårdsbruk definert ved type produksjon, geografisk plassering og bruksstørrelse. I noen grad grad trekkes også inntekts-strukturen i husholdningen og inntektsvariasjon innen gruppe inn. I den grad det har vært mulig, er årsaker til inntektsvariasjon drøftet. I tillegg er usikkerheten i målingen av arbeidsforbruk i jordbru-ket vurdert. En begrensning i prosjektet er at en ikke har hatt informasjon om størrelsen av underskudd i jord-bruksnæring. Det en har hatt informasjon om er overskuddet når dette er positivt. Bare for samlet næringsinntekt er negative overskudd observert. Datagrunnlaget for analysen omfatter 6 926 husholdninger i SSBs landbruksundersøkelse 2018 der en personlig bruker er registrert med enkeltpersonforetak. Landbruksundersøkelsen inneholder blant annet tall for arbeidsforbruk i kalenderåret 2017. Disse er supplert med inntektsdata fra husholdning-enes selvangivelser (dvs. bruker, eventuell ektefelle/samboer/partner og andre familiemedlemmer med samme bostedsadresse) og detaljerte data om enkeltvekster og husdyr fra Landbruksdirektora-tets statistikk for produksjonstilskudd i jordbruket...