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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.

2017

Sammendrag

Liermåsan like nord for Bjørkelangen er et torvuttak som er under avslutning på ca 1,2 km2. Lierelva renner forbi torvuttaket og rett inn i Bjørkelangen sentrum. Området har problemer med flom, og rapporten har utredet potensialet og metoder for hvordan Liermåsan kan brukes til fordrøyning for å dempe flommene. Areal- og volumberegninger viser at Liermåsan kan lagre fra ca 165000 m3 til ca 2400000 m3 etter hvor omfattende tiltak som gjøres. For å redusere en 20-årsflom til en 10-årsflom i en time trengs 26640 m3, for ett døgn ca 640000 m3. Tilsvarende kan en redusere en 100-årsflom til en 50-årsflom i en time med 35000 m3. Dette viser at arealet har potensiale for å dempe flomtoppene.....

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Sammendrag

Management of peat soils is regionally important as they cover large land areas and have important but conflicting ecosystems services. A recent management trend for drained peatlands is the control of greenhouse gases (GHG) by changes in agricultural practices, peatland restoration or paludiculture. Due to complex antagonistic controls of moisture, water table management can be difficult to use as a method for controlling GHG emissions. Past studies show that there is no obvious relationship between GHG emission rates and crop type, tillage intensity or fertilization rates. For drained peat soils, the best use options can vary from rewetting with reduced emission to efficient short term use to maximize the profit per amount of greenhouse gas emitted. The GHG accounting should consider the entire life cycle of the peatland and the socio-economic benefits peatlands provide locally. Cultivating energy crops is a viable option especially for wet peat soils with poor drainage, but harvesting remains a challenge due to tractability of wet soils. Paludiculture in lowland floodplains can be a tool to mitigate regional flooding allowing water to be stored on these lands without much harm to crops. This can also increase regional biodiversity providing important habitats for birds and moisture tolerant plant species. However, on many peatlands rewetting is not possible due to their position in the landscape and the associated difficulty to maintain a high stable water table. While the goal of rewetting often is to encourage the return of peat forming plants and the ecosystem services they provide such as carbon sequestration, it is not well known if these plants will grow on peat soils that have been altered by the process of drainage and management. Therefore, it is important to consider peat quality and hydrology when choosing management options. Mapping of sites is recommended as a management tool to guide actions. The environmental status and socio-economic importance of the sites should be assessed both for continued cultivation but also for other ecosystem services such as restoration and hydrological functions (flood control). Farmers need advice, tools and training to find the best after-use option. Biofuels might provide a cost-efficient after use option for some sites. Peat extraction followed by rewetting might provide a sustainable option as rewetting is often easier if the peat is removed, starting the peat accumulation from scratch. Also this provides a way to finance the after-use. As impacts of land use are uncertain, new policies should consider multiple benefits and decisions should be based on scientific evidence and field scale observations. The need to further understand the key processes and long term effects of field scale land use manipulations is evident. The recommended actions for peatlands should be based on local condition and socio-economic needs to outline intermediate and long term plans.

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Sammendrag

This concluding report contains all the monitoring data collected in the course of five years, from Jan. 2013 to Aug. 2017 from the protected archaeological deposits at Øvregaten 19, Bergen. The deposits had high contents of organic material and high water content before monitoring started. Data showed minimum temperatures close to 0-2°C under winter conditions and Maximum temperatures at 14°C during the first year of monitoring 2013. In 2014 the minimum temperature increased to 6-7°C and the maximum temperature increased to 17-18°C. Data recorded in 2015 showed minimum temperature 7-9°C and maximum temperature at 16-19°C. The average and median values calculated in the last two years 2016 & 2017 were increased to 22°C in the upper part of the pit and stable at 14°C in the deeper layers. This high temperature in the upper part of the pit, which is higher than mean ambient air temperature, may be due to the new house and the flagstones placed over and close to the pit where the monitoring equipment was installed.High soil moisture was found in all layers, and fluctuated with precipitation. This increased more frequently in 2014 and 2015 under periods with high precipitation. This high precipitation frequency and the infiltration of roof water has decreased the redox potential to more anoxic conditions, which is positive for the preservation of the archaeological remains.

Sammendrag

Rapporten gir resultatene av en multiparameteranalyse av vannkjemi (næringsstoffer og suspendert sediment) og om lag 20 ulike feltkarakteristika i leirvassdrag. Korrelasjonsmatrisene viser at det i overveiende grad er leirdekningsgrad som påvirker fosfornivået i skogsvassdrag, og leirdekningsgrad sammen med andel jordbruksareal i vassdrag med jordbruksaktivitet i nedbørfeltet. Resultatene er av betydning for gjennomføringen av vannforskriften, og er benyttet som grunnlag for anbefalinger om referansetilstand i leirvassdrag.

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Sammendrag

Green roofs are used increasingly to alleviate peaks of water discharge into the sewage systems in urban areas. Surface runoff from roofs contain pollutants from dry and wet deposition, and green roofs offer a possibility to reduce the amounts of pollutants in the water discharged from roofs by degradation and filtering. These pollutants would otherwise enter wastewater treatments plants and ultimately end up in sewage sludge that is spread on agricultural soils. The most common substrates used in green roofs have limited capacity for filtration and sorption. Also, more sustainable alternatives are sought, due to the high carbon footprint of these materials. Biochar is a carbon-rich material produced by pyrolysis of biomass, and several types of biochar have been described as good sorbents and filter materials. Biochar is also a light and carbon negative material, which may fulfill other desired criteria for new green roof substrates. We here report on an experiment where two types of biochar, produced from olive husks at 450 °C or from forest waste at 850 ° C were mixed with volcanic rock or peat, and tested for retention capacity of phenanthrene and six heavy metals in a column experiment with unsaturated gravimetric water flow lasting for 3 weeks. The results suggest that biochar as a component in green roof substrates perform better than traditional materials, concerning retention of the tested pollutants, and that different types of biochar have different properties in this respect.