Biografi

Bachelor- og mastergrad i agronomi og doktorgrad i naturvitenskap (Dr. rer. nat.) med fokus på jordvitenskap. Forskningen fokuserte på effekten av arealbruk og forvaltning på jordas C-innhold, og mekanismer for beskyttelse av organisk materiale i jorda gjennom organo-mineralforbindelser. Ledet prosjekter som krysser jordkvalitet, bærekraft og geovitenskap ved hjelp av avanserte metoder, inkludert 13C-NMR, SEM/TEM, STXM, NanoSIMS, FIB-SEM og stabile isotoper (13C og 15N).

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Sammendrag

Cover crops enhance soil quality and organic matter stability, yet the mechanisms linking belowground inputs to persistent soil organic matter (SOM) remain unclear. This study examined the effects of diversified cover cropping in barley systems on root biomass, SOM fractions, soil structure, microbial activity, and yield in central Norway (63.9° N), three years post-implementation. Six treatments were tested: (1) Control (barley without NPK), (2) Biochar-Fertilizer (barley + NPK + 3 Mg ha⁻¹ biochar), (3) Monocrop (barley), (4) Ryegrass (barley + ryegrass), (5) Clover (barley + ryegrass + white/red clover), and (6) Chicory (barley + ryegrass + red clover + chicory + bird’s-foot trefoil). Ryegrass and Clover systems produced 28.65 g m-² more root biomass at 0–13 cm (p < 0.05) and, along with Monocrop, stored 2.2 Mg ha-¹ more mineral-associated organic matter (MAOM) carbon and 0.2 Mg ha-¹ more MAOM nitrogen at 0–20 cm than other treatments. The Chicory system improved soil structure and biology, with higher aggregate stability, lower bulk density, and greater microbial abundance. Barley yields remained consistent across treatments, suggesting that cover cropping and low biochar inputs do not reduce productivity. Strong correlations (p < 0.01) between root biomass and MAOM stocks highlight root development as a key driver of SOM stabilization via organo-mineral associations. These findings underscore the role of root-enhancing cover crops in promoting MAOM formation and long-term SOM persistence, offering valuable insights for sustainable soil management.

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Sammendrag

Sewage sludge-derived biochar, a carbon-rich material produced by the pyrolysis of sewage sludge, has emerged as a promising amendment for enhancing the fertility and biological quality of nutrient-poor sandy soils in tropical regions. We investigated the effects of sewage sludge (SS) and its biochar (SSB) on microbial indicators, nutrient dynamics, and sugarcane biomass growth in sandy soil over 120 days. Treatments included individual applications of SS (40 Mg ha−1) and SSB (20 Mg ha−1), their combinations at 75:25, 50:50, and 25:75 SS:SSB ratios, a mineral fertilizer, and an unfertilized control. Microbial biomass carbon (Cmic), basal C-CO2 flux, metabolic (qCO2) and microbial (qMic) quotients were monitored, along with ammonium and nitrate levels, available phosphorus (P), and carbon stock. SS promoted a rapid rise in microbial activity and Cmic, whereas SSB sustained these effects over time, demonstrating complementary roles. The 75:25 combination exhibited the strongest synergistic response, enhancing microbial efficiency (higher qMic and lower qCO2), P availability, and carbon storage. Ammonium and nitrate peaked during early and mid-stages, respectively, with the highest values under SS. At the same time, P availability and soil carbon stocks were maximized under 75:25. Sugarcane biomass increased significantly in this treatment, despite foliar N and P concentrations remaining below sufficiency levels. These results highlight clear synergistic interactions between SS and SSB, emphasizing that the 75:25 combination offers a balanced strategy to improve nutrient cycling, microbial functionality, and carbon stabilization in tropical sandy soils.

Schematic illustration-SinoGrain III 050523

Divisjon for miljø og naturressurser

Sinograin III: Smart agricultural technology and waste-made biochar for food security, reduction of greenhouse gas (GHG) emission, and bio-and circular economy


The Sinograin III project’s overall objective is to contribute to the UN SDGs by widely implementing precision agriculture technologies and application of “waste-to-value” biochar products to achieve sustainable food production with minimized GHG emission, improve soil fertility and promote green growth/zero waste in modern agriculture in China.

Active Updated: 24.09.2024
End: okt 2027
Start: sep 2023