Vedlegg

CV

Biografi

Jeg er utdannet Cand. Scient. i bioteknologi/miljømikrobiologi fra Norges landbrukshøgskole, nå NMBU (1995-2000) hvor hovedoppgaven omhandlet bioremediering av jord forurenset med PCB ved bruk av genmodifiserte bakterier (Pseudomonas putida). Etter dette jobbet jeg en kort periode som høgskolelektor ved Høgskolen i Telemark hvor jeg underviste i bl.a. grunnleggende toksikologi og fysiologi. Jeg har videre jobbet i vel 14 år i Landbrukstilsynet/Mattilsynet med miljøvurderinger (eksponeringsvurdering/modellering samt risikovurdering) og godkjenning av plantevernmdler før jeg startet i en stipendiatstilling her i NBIO i august 2015. PhD-prosjektet er en del av Smartcrop-prosjektet. Planen er å ferdigstille en PhD-avhandling i løpet av januar 2019. Avhandlingens tittel er Effekten av frysing og tining på vanntransport og utlekking av plantevernmidler i delvis frossen jord. Fra 1. januar 2019 er jeg fast ansatt som forsker ved Avdeling pesticider og naturstoffkjemi hvor jeg bl.a. skal være prosjektleder for prosjektene "Dataverktøy for planlegging av vegetasjonssoner for redusert avrenning av plantevernmidler" og «Tabeller for utlekkingsrisiko til bruk ved planlegging av sprøyting», begge finansiert over Handlingsplan for bærekraftig bruk av plantevernmidler i 2019.

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Sammendrag

Limited knowledge and experimental data exist on pesticide leaching through partially frozen soil. The objective of this study was to better understand the complex processes of freezing and thawing and the effects these processes have on water flow and pesticide transport through soil. To achieve this we conducted a soil column irrigation experiment to quantify the transport of a non-reactive tracer and the herbicide MCPA in partially frozen soil. In total 40 intact topsoil and subsoil columns from two agricultural fields with contrasting soil types (silt and loam) in South-East Norway were used in this experiment. MCPA and bromide were applied on top of all columns. Half the columns were then frozen at −3 °C while the other half of the columns were stored at +4 °C. Columns were then subjected to repeated irrigation events at a rate of 5 mm artificial rainwater for 5 h at each event. Each irrigation was followed by 14-day periods of freezing or refrigeration. Percolate was collected and analysed for MCPA and bromide. The results show that nearly 100% more MCPA leached from frozen than unfrozen topsoil columns of Hov silt and Kroer loam soils. Leaching patterns of bromide and MCPA were very similar in frozen columns with high concentrations and clear peaks early in the irrigation process, and with lower concentrations leaching at later stages. Hardly any MCPA leached from unfrozen topsoil columns (0.4–0.5% of applied amount) and concentrations were very low. Bromide showed a different flow pattern indicating a more uniform advective-dispersive transport process in the unfrozen columns with higher con- centrations leaching but without clear concentration peaks. This study documents that pesticides can be pre- ferentially transported through soil macropores at relatively high concentrations in partially frozen soil. These findings indicate, that monitoring programs should include sampling during snow melt or early spring in areas were soil frost is common as this period could imply exposure peaks in groundwater or surface water.

Sammendrag

Freezing and thawing have large effects on water flow in soils since ice may block a large part of the pore space and thereby prevent infiltration and flow through the soil. This, in turn, may have consequences for contaminant transport. For example, transport of solutes contained at or close to the soil surface can be rapidly transported through frozen soils in large pores that were air filled at the time of freezing. Accounting for freezing and thawing could potentially improve model predictions used for risk assessment of contaminant leaching. A few numerical models of water flow through soil accounts for freezing by coupling Richards’ equation and the heat flow equation using of the generalized Clapeyron equation, which relates the capillary pressure to temperature during phase change. However, these models are not applicable to macroporous soils. The objective of this study was to develop and evaluate a dual-permeability approach for simulating water flow in soil under freezing and thawing conditions. To achieve this we extended the widely used MACRO-model for water flow and solute transport in macroporous soil. Richards’ equation and the heat flow equation were loosely coupled using the Clapeyron equation for the soil micropore domain. In accordance with the original MACRO model, capillary forces were neglected for the macropore domain and conductive heat flow in the macropores was not accounted for. Freezing and thawing of macropore water, hence, were solely governed by heat exchange between the pore domains. This exchange included a first-order heat conduction term depending on the temperature difference between domains and the diffusion pathlength (a proxy variable related to the distance between macropores) and convective heat flow. As far as we know, there are no analytical solutions available for water flow during freezing and thawing and laboratory data is limited for evaluation of water flow through macropores. In order to evaluate the new model approach we therefore first compared simulation results of water flows during freezing for the micropore domain to existing literature data. Our model was shown to give similar results as other available models. We then compared the first-order conductive heat exchange during freezing to a full numerical solution of heat conduction. Finally, simulations were run for water flow through frozen soil with initially air-filled macropores for different boundary conditions. Simulation results were sensitive to parameters governing the heat exchange between pore domains for both test cases.

Sammendrag

Climate change will most probably lead to more frequent freezing and thawing episodes in soil during winter. This can have a profound effect on transport of water and solutes in soil. Studies with inactive tracers and field measurements indicate that solutes and pesticides leach to groundwater and surface water at relatively high concentrations during snowmelt and freezing/thawing episodes during winter and spring. The effect of freezing and thawing and preferential transport of pesticides in soil has not been studied to great extent and the processes of water flow and pesticide transport through frozen soil are still not well understood. A leaching experiment with undisturbed soil columns from two different agricultural soils (silt and loam) was performed to study water flow and pesticide transport in frozen soils under cold climate conditions. The objective was to see whether the transport of water and pesticides in frozen soil was significantly different from transport in unfrozen soil. The results show a great difference in the transport of bromide and MCPA between partially frozen and non-frozen soil and that preferential flow in macropores in the frozen soil can result in increased transport of pesticides vertically towards drainpipes or groundwater.

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Sammendrag

Limited knowledge and experimental data exist on pesticide leaching through partially frozen soil. The objective of this study was to better understand the complex processes of freezing and thawing and the effects these processes have on water flow and pesticide transport through soil. To achieve this we conducted a soil column irrigation experiment to quantify the transport of a non-reactive tracer and the herbicide MCPA in partially frozen soil. In total 40 intact topsoil and subsoil columns from two agricultural fields with contrasting soil types (silt and loam) in South-East Norway were used in this experiment. MCPA and bromide were applied on top of all columns. Half the columns were then frozen at −3 °C while the other half of the columns were stored at +4 °C. Columns were then subjected to repeated irrigation events at a rate of 5 mm artificial rainwater for 5 h at each event. Each irrigation was followed by 14-day periods of freezing or refrigeration. Percolate was collected and analysed for MCPA and bromide. The results show that nearly 100% more MCPA leached from frozen than unfrozen topsoil columns of Hov silt and Kroer loam soils. Leaching patterns of bromide and MCPA were very similar in frozen columns with high concentrations and clear peaks early in the irrigation process, and with lower concentrations leaching at later stages. Hardly any MCPA leached from unfrozen topsoil columns (0.4–0.5% of applied amount) and concentrations were very low. Bromide showed a different flow pattern indicating a more uniform advective-dispersive transport process in the unfrozen columns with higher con- centrations leaching but without clear concentration peaks. This study documents that pesticides can be pre- ferentially transported through soil macropores at relatively high concentrations in partially frozen soil. These findings indicate, that monitoring programs should include sampling during snow melt or early spring in areas were soil frost is common as this period could imply exposure peaks in groundwater or surface water.

Sammendrag

Til tross for at lavdosemidler har vært brukt i Norge i flere tiår, vet vi lite om hvordan stoffene oppfører seg i miljøet under norske forhold. Våre forsøk viser at enkelte lavdosemidler og nedbrytingsprodukter er mobile og transporteres bort fra kornfeltet gjennom dren og avrenning. Målte konsentrasjoner er lave, men kan overstige norske verdier for miljøfarlighet.

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Sammendrag

This is a final report for the project Norwegian Scenarios from the periods 1999-2002 and 2005- 2008, mainly focusing on the simulations done with the models MACRO and PRZM. The aim of this project was to improve the risk assessment work in Norway by establishing surface- and groundwater scenarios which could be representative for Norwegian conditions and to later use these for approval of new pesticides. This project has been a cooperation between Bioforsk Plantehelse, Norwegian University of Life Sciences and the Norwegian Food Safety Authority.

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Sammendrag

This is a final report for the project Norwegian Scenarios II, part two, that has been performed in collaboration between Bioforsk Plant Health and Plant Protection, The Norwegian University of Life Sciences and the Norwegian Food Safety Authority. The aim of the project was to establish Norwegian scenarios for the models PRZM and MACRO and to use them for approval of new pesticides.

Sammendrag

Dette er en avslutningsrapport for prosjektet "Norske scenarier II" som har vært et samarbeid mellom Bioforsk Plantehelse, Universitetet for miljø og biovitenskap (UMB) og Mattilsynet. Prosjektet har hatt som mål å etablere modell-scenarier for modellene MACRO og PRZM3 til beregning av overflateavrenning av plantevernmidler i forbindelse med godkjenning av nye plantevernmidler i Norge.

Sammendrag

Brukere av plantevernmidler ønsker å produsere trygg mat og forvalte naturressursene på en god måte. Kunnskap om riktig bruk og handtering av plantevernmidlene er en forutsetning for å oppfylle dette ønsket. Slike kunnskaper vil dessuten bidra til bedre økonomi i planteproduksjonen. Med "Handlingsplan for redusert bruk av plantevernmidler (1990-1994)" ønsket Stortinget å legge til rette for, og sikre slike kunnskaper hos alle brukere av plantevernmidler gjennom et organisert kursopplegg med avsluttende eksamen som gir rett til et personlig autorisasjonsbevis også kalt sprøytesertifikat. Etter evalueringg av handlingsplanen vedtok Landbruksdepartementet en ny handlingsplan "Handlingsplan for redusert risiko ved bruk av plantevernmidler (1998-2002)". I denne videreføres autorisasjonsordningen. Denne boka gir deg oppdatert basiskunnskap om riktig bruk og handtering av plantevernmidler. Boka inngår i kursmateriellet til autorisasjonsordningen for handtering og bruk av plantevernmidler.