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.
2006
Forfattere
Petter SnilsbergSammendrag
Grunnlag, teori, metoder og eksempler på prøvetaking av miljøparametre i jord, grunnvann, overflatevann og sedimenter
Forfattere
Trond MæhlumSammendrag
Det er ikke registrert sammendrag
Forfattere
Ivar GjerdeSammendrag
Det er ikke registrert sammendrag
Forfattere
Ingvild WartiainenSammendrag
Gjennomgang av hva man i dag vet om hvordan forurensingen fra smelteverkene i Nikel og Pechenga påvirker natur og mennesker i nærområdene i Norge og Russland.
Forfattere
Astrid Johansen Mats HøglindSammendrag
To examine the effect of herbage allowance and concentrate supply on milk yield and milk composistion by dairy cows grazing on grass/white clover pastures, two experiments have been carried out in Norway. Twenty-eight spring-calving cows were allocated to four groups offered either ot two concentrate leves whithin two herbage allowances. Milk yield and milk fat was significantly higher for cows offered 18 vs 12 kg DM herbage in one experiment. The milk production was not significantly affected by concentrate level in any of the two experiments.
Sammendrag
Chemical recalcitrance of specific molecules is one of the factors governing organic matter stabilization in soils. Little is known about the relationship between the chemical nature and the dynamics of soil organic matter at the long-term scale. Lignin molecules are abundant in plant tissues and are generally considered as slowly biodegradable in soils. In a previous study, using compound specific isotopic tracer techniques applied to agricultural lands converted from C3 to C4 cropping, we showed that lignin turnover was faster than that of total organic carbon. Lignin dynamics was well described by a two-pool model, distinguishing lignins in fresh plant residues and those more closely associated to the soil matrix. These two pools may be transformed into non-lignin products, which includes CO2, microbial biomass and chemical substances, which are no longer recognized as lignin derivatives. The aim of the present work was to study the nature and dynamics of these non lignin products formed during lignin degradation in a laboratory incubation of 13C-labelled lignin with soil. Maize plants were grown for 1 month under 13C enriched CO2. The lignins of leaves and stems were isolated after treatment with cellulolytic enzymes and solubilization in dioxane:water (1:9). The Milled Maize Lignin (MML) obtained had a 13C abundance of 1.4 %. Solid-state 13C NMR spectroscopy of MML before analysis showed that the isolation method produces a lignin-cellulose complex, as indicated by the presence of some polysaccharides (the 60-115 ppm region represented about 40 % of total C of isolated lignins). Lignins were incubated with soil (1 mg lignin/g soil) at 20°C in sealed glass jars and analyzed after 1, 2, 4, 8, 16, 32 and 48 weeks. A control sample was incubated without lignin. We monitored the mineralization, solubilization and incorporation in the microbial biomass of lignin C by measuring 13C enrichments in respired CO2, water-soluble fractions, and fumigated biomass, respectively. Lignins remaining in incubated soils were quantified by CuO oxidation and the 13C contents of vanillyl, syringyl and cinnamyl units (VSC) were measured. After 4 months, 3% of the 13C of the labelled lignin was mineralized. This mineralization rate was less than that found by Martin and Haider (1979) for DHP lignins but more than the 5% per year found in situ by Dignac et al. (2005). Less than 0.5% of incubated lignin C was water soluble and 0.5 % was incorporated into the soil microbial biomass. The main part (96%) of incubated MML remained in soil. We used compound-specific isotopic analysis of the CuO oxidation products and pyrolysis analysis to estimate the proportion of intact lignins remaining in the soil.
Sammendrag
The minirhizotron technique provides the opportunity to perform in situ measurements of fine root dynamics and obtain accurate estimates of fine root production and turnover. The objective of the present work was to determine the fine root longevity and mycorrhization in a Norway spruce chronosequence. The study was carried out on four stands of planted Norway spruce (Picea abies), approximately 10, 30, 60 and 120 years old, during 2001 and 2002. The stands were located at Nordmoen, a plain of sandy deposits in southeast Norway (60o15 N, 11o06 E). For the root turnover study, altogether 60 minirhizotrones were installed and images were processed.Individual fine roots were identified, their mycorrhization assessed, appearance and possible disappearance dated, and growth in length measured. The data set was subjected to a survival analysis, using a Kaplan-Meier product-limit approach. The minirhizotron samples were stratified according to stand age class, and Coxs F-test was used to analyze differences in survival estimates. The analysis may also be extended to consider other covariates such as tree species (spruce, pine or birch), understory vegetation, or soil depth. Typical survival function estimates will be presented, and the influence of stand age on the mycorrhization and the dynamics of the fine roots will be discussed.
Sammendrag
I august 2006 vart det for første gong gjort funn av mjøldogg (Erysiphe syringae syn. Microsphaera syringae ) på vanleg syrin (Syringa vulgaris) ved fleire lokalitetar i Oslo, Akershus, Buskerud og Telemark.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Mål Studenten skal ha innsikt i kvantitative metoder for å beskrive egenskaper av grunnvann inklusiv strømning av vann og spredning av forurensinger. Kvantitativ analyse av transport av vann og løste stoffer i porøse medier under mettede forhold. Kunnskapen er viktig i forbindelse med effektvurdering av menneskelig inngrep i grunnvannsystemer.Bruk av kvantitative metoder, inklusiv storskala grunnvannsmodeller som predikeringsverktøy. Å kunne vurdere risiko for irreversible endringer i grunnvannsressurser både når det gjelder kvantitet og kvalitet som en følge av menneskelig inngrep er viktig for en god ressursforvaltning. Rent grunnvann er en viktig naturressurs. Innhold 1. Forelesninger teori 2. Regneøvelser 3. Innleveringsoppgaver (teller for sluttkarakter) 4. Innføring i bruk av modellen MODFLOW 5. Innleveringsoppgaver MODFLOW (skal innleveres og godkjennes)