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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.

2019

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Sammendrag

A novel method for age-independent site index estimation is demonstrated using repeated single-tree airborne laser scanning (ALS) data. A spruce-dominated study area of 114 km2 in southern Norway was covered by single-tree ALS twice, i.e. in 2008 and 2014. We identified top height trees wall-to-wall, and for each of them we derived based on the two heights and the 6-year period length. We reconstructed past, annual height growth in a field campaign on 31 sample trees, and this showed good correspondence with ALS based heights. We found a considerable increase in site index, i.e. about 5 m in the H40 system, from the old site index values. This increase corresponded to a productivity increase of 62%. This increase appeared to mainly represent a real temporal trend caused by changing growing conditions. In addition, the increase could partly result from underestimation in old site index values. The method has the advantages of not requiring tree-age data, of representing current growing conditions, and as well that it is a cost-effective method with wall-towall coverage. In slow-growing forests and short time periods, the method is least reliable due to possible systematic differences in canopy penetration between repeated ALS scans.

Sammendrag

På oppdrag fra vannområdet Bunnefjorden med Årungen- og Gjersjøvassdraget (PURA) er den empiriske modellen Agricat 2 brukt til å beregne potensialet for erosjon og fosforavrenning fra jordbruksarealer i 16 tiltaksområder, ved faktisk drift i 2018. Arealfordelingen av faktisk drift (vekst, jordarbeiding og miljøtiltak) i 2018 har framkommet av registerdata fra Landbruksdirektoratet og føringer/informasjon fra Follo Landbrukskontor, og er fordelt på de dyrka arealene etter bestemte rutiner i modellen. Arealfordelingsrutinen i modellen ga følgende utbredelse av kombinasjon vekst/jordarbeiding i vannområdet for 2018: 28 % stubb (jordarbeiding vår eller direktesåing), 20 % gras, 17 % vårkorn med høstpløying, 20 % høstkorn med høstpløying, 13 % høstharving til vår- og høstkorn, og 2 % poteter og grønnsaker. Arealfordelingen varierte mellom tiltaksområder. Eksisterende grasdekte buffersoner og fangdammer inngikk også i beregningene. Jord- og fosfortap i vannområdet PURA i 2018 ble beregnet til henholdsvis 3,8 kilotonn SS og 6,4 tonn TP. Resultatene for 2018 er ikke direkte sammenliknbare med resultatene fra foregående år pga. at ny beregningsmetode med nye erosjonsrisikokart som grunnlag er brukt for 2018. For individuelle tiltaksområder varierte jordtapet fra nær 0 til 2 kilotonn, og fosfortap fra nær 0 til 3 tonn. Forskjeller i drift bidro til å forklare forskjellene mellom tiltaksområder.

Sammendrag

Nutrient pollution can have a negative impact on the aquatic environment, with loss of biodiversity, toxic algal blooms, and a deficiency in dissolved oxygen in surface waters. Agricultural production is one of the main contributors to these problems; this article provides an overview of and background for the main biogeochemical processes causing agricultural nutrient pollution of surface waters. It discusses the main features of the agricultural impact on nutrient loads to surface waters, focusing on nitrogen and phosphorus, and describes some of the main characteristics of agricultural management, including processes and pathways from soil to surface waters. An overview of mitigation measures to reduce pollution, retention in the landscape, and challenges regarding quantification of nutrient losses are also dealt with. Examples are presented from different spatial scales, from field and catchment to river basin scale.

Sammendrag

Agroforestry can be defined as sustainable and multifunctional land-use systems where trees are managed together with agricultural crops or livestock on the same piece of land. In the northern periphery area, agroforestry has a long history with woodland grazing, reindeer husbandry and gathering of different non-wood forest resources as herbs, mushrooms and berries. Traditional agroforestry has gradually disappeared during the 20th century with the intensification of agriculture and forestry. Currently agroforestry systems are gaining new interest, not only from farmers but also from politicians, as this practice can possibly contribute to a more sustainable way of agricultural production. In the northern periphery area, the benefits of agroforestry practices can be manifold not only promoting traditional practices, but also novel systems with the use of new technology. In addition, agroforestry has environmental benefits as a method for conservation and enhancement of biodiversity, improved nutrient cycling, and water quality. Soil humus layer will also increase with several agroforestry systems leading to carbon sequestration. Here we present an overview of agroforestry practices in the Nordic countries and the use of non-wood forest resources with the emphasis on wild berries.