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.
2008
Sammendrag
Hovedformålet med kurset er å gi tilsatte i kommunene kunnskap om forvaltning og skjøtsel av kulturlandskapet
Forfattere
Liv Guri Velle Ann Norderhaug S. ØpstadSammendrag
Feral sheep in coastal heaths - developing sustainable agriculture in vulnerable cultural landscapes.
Forfattere
Nils VagstadSammendrag
Det er ikke registrert sammendrag
Forfattere
Ragnhild Nærstad Lars MøllerSammendrag
Three years trials with cyazofamid (Ranman plus the adjuvant Additive for Ranman) shows god effect against potato late blight compared to untreated. The effect against potato late blight has been on the same level as other tested fungicides with no significant difference. In 2008 Ranman has been tested in combination with two different dose rates of the adjuvant Renol. The two trials have shown good effect of Ranman in combination with Renol with no significant difference in control of late blight between the tested dose rates of Renol and no significant difference between the two adjuvants Renol and Additive for Ranman.
Forfattere
Lukas Gudmundsson Holger LangeSammendrag
Many time series analysis methods depend on equally spaced observations with no data point missing. If this condition is met, powerful techniques are available that identify temporal structures such as trends, periodic phenomena or nonlinear dynamics. Unfortunately, most observations of natural systems, in particular over longer periods of time such as decades, are prone to sampling errors leading to missing points in the observations. Singular System Analysis (SSA) is a powerful tool to extract the dynamics contained in time series at arbitrary temporal scales. In its original formulation, however, SSA relies as well on data without missing values. Recently several extensions to SSA have been proposed which are designed to fill the gaps, exploiting the dynamics contained in the sampled parts of the series to estimate the structure of the signal at the position of missing values. SSA consists of two steps: Decomposition and reconstruction. For the decomposition the time series under investigation is embedded into a trajectory matrix and decomposed with singular value decomposition. The reconstruction (of selected components) of the time series employs the left and right singular values to obtain additive components of the time series. In the original variant of SSA both steps are dependent on gap free data sets. In order to evaluate the power of SSA for time series with missing values we simulate 1000 series of different processes - ARMA(2,3) and red noise contaminated sine waves. Several gap–schemes (continuous, periodic, and uniformly distributed) are used to create time series with up to 50% (artificially) missing values. SSA is applied on all surrogate series. The decomposition as well as the reconstruction is compared systematically to the gap free benchmark. In addition we evaluate the ability of SSA to capture periodic phenomena in the presence of missing values and whether periodical gaps lead to the identification of spurious periods. We demonstrate that SSA successfully reproduces the signal part of time series (i.e. components with large eigenvalues) for up to 30% missing values. For less significant components with higher rank numbers, the presence of gaps is increasingly deleterious. A number of distributed smaller gaps, a situation most likely to occur in observations, spoils the analysis to a much lesser degree than a single large gap. Thus, these new variants of SSA substantially enlarge the set of observational time series amenable to the analysis, and allows for obtaining precise estimates of the signal at the position of missing data points.
Sammendrag
Many time series analysis methods depend on equally spaced observations with no data point missing. If this condition is met, powerful techniques are available that identify temporal structures such as trends or periodic phenomena or nonlinear dynamics. Unfortunately, most of observations of natural systems, in particular over longer periods of time such as decades, are prone to sampling errors leading to missing points in the observations. Singular System Analysis (SSA) is a powerful tool to extract the dynamics contained in time series at arbitrary temporal scales...
Sammendrag
Kikkutstua ligger ved Bjørnsjøen i Nordmarka og eies av Skiforeningen. I 2007 ble det installert et nytt renseanlegg ved Kikutstua. Anlegget er et filterbedanlegg av typen "NATURren" og er levert av Bokn Plast AS. Renseanlegget er etablert uten godkjenning fra Oslo kommune. Anlegget tar i dag i mot gråvann fra Kikutstua. I følge Bokn Plast AS er anlegget beregnet for mottak av både gråvann og toalettavløp. Renset vann ledes til nedbørsfeltet til Maridalsvannet der det er krav om at toalettavløp skal ledes til samletank. Anlegget har fått midlertidig utslippstillatelse fra kommunen, men kun for rensing av gråvann. Bioforsk Jord og miljø har utarbeidet en rapport som beskriver hvordan anlegget er dimensjonert og bygget opp. Dimensjonering og utforming er sammenholdt med anvisningene i VA/Miljøblad nr. 49, Våtmarksfiltre. Skiforeningen har så langt det har vært mulig bidratt med opplysninger om anleggets dimensjonering og oppbygging.
Sammendrag
I 2004 Phytophthora capsici ble funnet i veksthusagurk i Norge.
Forfattere
Migel de Cara M Santos Maria Luz Herrero May Bente Brurberg J.C. Tello MarquinaSammendrag
P.delinese ble funnet for første gang i jord i Honduras og Guatemale. Et smitteforsøk bekreftet at P.deliense er patogen på melon
Forfattere
Merete Wiken Dees Carl Jonas Jorge Spetz dag-ragnar blystadSammendrag
A virus (isolate 10306) was isolated from bait plants (Nicotiana sp.) grown in a soil sample collected from cultivated soil in the eastern part of Norway. Preliminary results from electron microscopy identified isolate 10306 as a putative member of the genus Potexvirus based on particle morphology. Molecular and biological methods were further used to determine the coat protein (CP) sequence and the host range of isolate 10306, respectively. Potexvirus-specific degenerate primers were designed and used to amplify a ~300 nucleotide fragment belonging to the RNA-dependent RNA-polymerase region of the viral genome by reverse-transcription PCR (RT-PCR). Based on the results from the sequencing analysis, new specific primers were designed to amplify a fragment encompassing the CP gene. Furthermore, isolate 10306 was mechanically inoculated to different test plants and was found to infect systemically eight plant species belonging to five families. CP sequence comparisons, on amino acid and nucleotide level, as well as phylogenetic analysis identified isolate 10306 as Tulip virus X (TVX). However, results from the host range studies differed from the ones previously published for this virus, suggesting that isolate 10306 could be considered a different strain of TVX. This is the first report of TVX in Norway.