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.
2010
Sammendrag
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Sammendrag
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Sammendrag
I løpet av de siste årene har det vært økt oppmerksomhet på de uheldige miljøkonsekvensene som følge av høy fosforavrenning til utsatte vann og vassdrag. I samme periode er innsatsen knyttet til fosforgjødsling styrket betydelig. Som en følge av dette er nå normen for fosforgjødsling til korn, eng/beite og potet redusert og det er utarbeidet en ny og nedjustert korreksjonskurve for fosforgjødsling i forhold til jordas P-AL-nivå. Etter de nye gjødslingsanbefalingene til korn og eng anbefales det å gjødsle med like mye fosfor som det fjernes med avlingene når P-AL er 5-7. Det er mye som tyder på at det gjødsles med fosfor en god del over norm i flere av feltene, spesielt der det er mye husdyr.
Forfattere
Trond MæhlumSammendrag
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Sammendrag
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Forfattere
Jørn-Frode Nordbakken Tonje Økland Ingvald Røsberg Gunnar EnganSammendrag
Vegetasjonsovervåkingen i granskog ble etablert ved Norsk institutt for jord- og skogkartlegging (fra 2006: Norsk institutt for skog og landskap) i 1988. Samme år ble det også etablert tilsvarende overvåking i Solhomfjell-området (Gjerstad, Aust-Agder) i regi av Universitetet i Oslo/Miljøverndepartementet. I regi av Norsk institutt for jord- og skogkartlegging ble det etablert og analysert to områder pr år fra 1988 til 1992, til sammen 10 områder. Prøveflatene i Gutulia ble første gang analysert i 1989. Etter 2004 har Direktoratet for naturforvaltning finansiert vegetasjonsovervåkingen i granskog gjennom TOV-programmet, men i noe redusert omfang. Metodene for overvåkingen av markvegetasjon ble i 1988 utviklet for å overvåke effekter av langtransportert luftforurensing, men har også vist seg godt egnet til å fange opp effekter av klimaendringer på markvegetasjonen. De permanente vegetasjonsflatene i Gutulia har tidligere vært analysert i 1989, 1994, 1999, og 2004 (femårig omløpstid). Reanalyseringen i 2009 var således 5. gangs analyse av disse prøveflatene....
Sammendrag
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Forfattere
Aldo Marchetto Rosario Mosello Gabriele A. Tartari Kirsti Derome Nils König Nicholas Clarke Anna KowalskaSammendrag
A second Working Ring Test (WRT) was organised within the framework of the EU/Life+ FutMon Project (`Further Development and Implementation of an EU-level Forest Monitoring System`, LIFE07 ENV/D/000218), to evaluate the overall performance of the laboratories responsible for analysing atmospheric deposition and soil solution samples in European forests, and to verify improvements in the analytical quality resulting from the QA/QC work carried out in the laboratories which participated in previous WRTs organized in the framework of the UN/ECE ICP Forests Monitoring Programme. The WRT was carried out in accordance with International ISO and ILAG guide proficiency test both for sample preparation and numerical elaboration of the results. Five natural atmospheric deposition and soil solution samples and 3 synthetic solutions were distributed to 42 laboratories for analysis using their routine methods for the following variables: pH, conductivity, calcium, magnesium, sodium, potassium, ammonium, sulphate, nitrate, chloride, total alkalinity, total dissolved nitrogen (TDN), dissolved organic carbon (DOC). Two tolerable limits were defined for each variable on the basis of the measured value, the results of previous WRTs, a comparison with the Data Quality Objectives of other international networks, and the importance of the variable in deposition and soil solution monitoring. In the ring test 12% of the results from all the laboratories did not fall within the tolerable limits. This enabled us to identify those variables and laboratories for which improvements in analytical performance are required. The results of the exercise clearly show that the use of data check procedures, as described in the ICP Forests manual for sampling and analysis of atmospheric deposition, makes it possible to detect the presence of inaccurate or outlying results, and would therefore greatly improve the overall performance of the laboratories. A discussion of the improvement of the results in this WRT compared to the previous WRTs is also included, showing a relevant improvent for several variables and underlining the importance of participating to these exercises for the overall analytical quality of the monitoring network.
Sammendrag
Concentrations of dissolved organic carbon (DOC) in throughfall and soil solutions at 5, 15 and 40-cm depth were studied in 16 Norway spruce and two Scots pine plots throughout Norway between 1996 and 2006 (Wu et al. 2010a). Average DOC concentrations ranged from 2.3 to 23.1 mg/l and from 1.1 to 53.5 mg/l in throughfall water and soil solutions, respectively. Concentrations of DOC in throughfall and soil waters varied seasonally at most plots with peaks in the growing season. In contrast to reported positive long-term trends in DOC concentrations in surface waters between 1986 and 2003, soil water data from 1996 to 2006 showed largely negative trends in DOC concentrations and no significant trends in throughfall. However, regression analysis for individual sites, particularly at 5- and 15-cm soil depths, showed that DOC concentrations in soil water were significantly and negatively related to non-marine sulphate and chloride. Further studies were carried out on dissolved organic nitrogen (DON, Wu et al. 2010b). Dissolved organic nitrogen (DON) concentrations were significantly and positively correlated to DOC concentrations in throughfall (r2=0.72, p<0.0001) and soil water at 5, 15, and 40 cm (r2=0.86, 0.32, and 0.84 and p<0.0001, 0.04, and <0.0001, respectively). At most sites, the annual median DOC/DON ratio in throughfall ranged from 20.3 to 55.5, while values in soil water were higher, ranging from 24.5 to 81.3 but gradually decreasing with soil depth. DON concentrations varied seasonally in throughfall at many plots and in soil water at 5 cm depth at one plot only, with higher values in the growing season, but there was no noticeable seasonality at greater depth. The ratios of DOC/DON in soil water were significantly positively related to the C/N ratio in soil at the same depth. Above-ground litter input was the main factor having a significant, negative relationship to DOC/DON in soil water at all depths studied. This might reflect the effect of site conditions on both DOC/DON ratios and litter quantity. A comparison of DOC and DON concentrations and fluxes at two Norwegian sites (Birkenes and Hirkjølen) and five Finnish Level II plots (Tammela, Juupajoki, Uusikaarlepyy, Kivalo and Pallasjärvi) showed no obvious correlation between concentrations and site and stand properties such as growing season length, temperature, precipitation, stand age, or soil C or N. DOC concentrations in the O horizon could not be linked to N deposition. However, there were clear within-site seasonal trends, compatible with an effect of temperature on microbial activity.
Forfattere
Knut Rydgren Jørn-Frode Nordbakken Ingvild Austad Inger Auestad Einar HeegaardSammendrag
Seminatural grasslands and their species and populations are declining rapidly throughout Europe, bringing about a need for successful vegetation recreation methods. To maintain biodiversity and ecological services of seminatural grasslands, we need more nowledge on the relative performance of different recreation methods. In a replicated experiment in western Norway, we evaluated two hay transfer methods (hard or light raking of local hay), sowing of local seeds and natural regeneration for recreating seminatural grassland in a road verge. We compared treated trial plots with their respective donor plots (where hay and seeds were harvested) for three successive years by evaluating vegetation cover, species richness and species transfer rates, and vegetation dynamics analysed by Bray–Curtis compositional dissimilarity (BC) and GNMDS (Global NonMetric Multidimensional Scaling) ordination. Vegetation cover at the trial site exceeded that of donor sites in three years. Transfer rates of common species were high for seed sowing and both hay transfer procedures. Species composition in trial plots for all three treatments became significantly more similar to donor plots, but was still relatively dissimilar after three years. Natural regeneration showed a different temporal pattern and also had a higher successional rate. The species composition of the other treatments followed the same trajectory toward the donor sites as revealed by GNMDS. We found relatively small differences between the two hay transfer methods and seed sowing. Transfer of local hay therefore appears to be a successful method of establishing local species when recreating seminatural grasslands, and is generally cheaper than using commercial local seed mixtures.