Kjersti Holt Hanssen

Forsker

(+47) 996 44 123
kjersti.hanssen@nibio.no

Sted
Ås - Bygg H8

Besøksadresse
Høgskoleveien 8, 1433 Ås

Biografi

Utdanning: Naturforvalter fra Norges landbrukshøgskole (nå NMBU) 1993. Doktorgrad fra Institutt for skogfag, NLH 2002.
 
Forskningsfelt: Skogskjøtsel, særlig knyttet til ulike hogstmetoder, foryngelse av skog, gjødsling og næringsstoffer.

Les mer

Sammendrag

Biochar, a carbon‐rich product of pyrolysis, is increasingly considered for soil amendment and climate change mitigation due to its potential to enhance soil properties and sequester carbon. However, its effects on tree growth in forest ecosystems remain uncertain. This study investigated the impact of biochar and nitrogen‐enriched biochar on the growth of two middle‐aged (approximately 60‐year‐old) Scots pine stands in southeastern Norway. Both stands were characterized by medium site indices and podzolic soils. In replicated field experiments, we applied four treatments consisting of an unfertilized control, and addition of biochar (2.5 t ha −1 ), nitrogen fertilizer (150 kg N ha −1 ), or biochar loaded with nitrogen (2.5 t biochar +150 kg N ha −1 ). The biochar was produced by pyrolysis of Norway spruce wood chips at 600°C. After 5 years, only treatments containing added nitrogen (either as mineral fertilizer or as nutrient‐enriched biochar) significantly increased basal area and volume growth compared to control. No significant difference in timing or magnitude of effects was observed between the nitrogen and biochar + nitrogen treatments, except better annual growth in the combined treatment the third year after fertilization, indicating rapid nitrogen release and uptake regardless of carrier. Pure biochar did not stimulate tree growth. While biochar did not negatively affect growth, its direct role as a growth stimulant was not supported under these conditions, at least in the short‐term with the dose of 2.5 t ha −1 . Further research is needed across different forest ages, site types, and application rates to fully understand biochar's potential in forestry.

MB1 Gravemaskin Ole Håkon Moberget - Foto Kjersti Holt Hanssen

Divisjon for skog og utmark

Markberedning og karbon


«Markberedning og karbon» er et samarbeidsprosjekt mellom næringsaktørene i Innlandet, Statsforvalteren i Innlandet, Skogkurs og forskningsinstitusjonene i skogbruket i Norge, med Glommen Mjøsen Skog som prosjekteier. Prosjektet har som mål å dokumentere markberedningens effekt på karbonbalansen i skogøkosystemet gjennom å måle lager av karbon, samt utslipp og opptak, i markberedt skog og kontrollflater.

Aktiv Sist oppdatert: 21.05.2025
Slutt: des 2026
Start: apr 2023
Skogskader Ørsta Lars Dalen 20160412

Divisjon for bioteknologi og plantehelse

FORESIGHT: Forest opportunities, risks and ecosystem services in a changing climate in Norway


Forest ecosystems are increasingly under pressure from climate change, emerging pests and pathogens, and more frequent extreme weather events. When such disturbances occur simultaneously—or interact with one another—the risk of severe damage can increase substantially. The FORESIGHT project aims to understand these complex, interacting challenges and to translate this knowledge into practical applications.

Aktiv Sist oppdatert: 26.02.2026
Slutt: jan 2029
Start: jan 2026
Skogskader Ørsta Lars Dalen 20160412

Divisjon for bioteknologi og plantehelse

FORESIGHT: Forest opportunities, risks and ecosystem services in a changing climate in Norway


Skog er i stadig større grad utsatt for press fra klimaendringer, nye skadegjørere og mer ekstremvær. Når slike forstyrrelser opptrer samtidig – eller påvirker hverandre – kan risikoen for store skader øke kraftig. FORESIGHT-prosjektet tar mål av seg til å forstå nettopp disse sammensatte utfordringene, og gjøre kunnskapen nyttig i praksis.

Aktiv Sist oppdatert: 25.07.2026
Slutt: jan 2029
Start: jan 2026
3D_gjengivelse av skog_Foto Stefano Puliti NIBIO

Divisjon for skog og utmark

SFI SmartForest: Bringing Industry 4.0 to the Norwegian forest sector


SmartForest will position the Norwegian forest sector at the forefront of digitalization resulting in large efficiency gains in the forest sector, increased production, reduced environmental impacts, and significant climate benefits. SmartForest will result in a series of innovations and be the catalyst for an internationally competitive forest-tech sector in Norway. The fundamental components for achieving this are in place; a unified and committed forest sector, a leading R&D environment, and a series of progressive data and technology companies. 

Aktiv Sist oppdatert: 06.05.2026
Slutt: sep 2028
Start: okt 2020