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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.

2003

Sammendrag

Hydrological models are the foundation for prediction of erosion and losses of nutrients, pesticides and other pollutants to water resources. In South-east Norway the winter season is the most important hydrological period of the year, and it is characterised by sub-zero temperatures, soil frost and snow. It is therefore necessary that models can simulate these conditions properly. We tested the Coupled mass and heat balance model for soil-plant-atmosphere systems (CoupModel) on experimental data from winter 2000-01. Snow depths, soil temperatures, liquid and total water content were measured in a farm field in the Skuterud catchment, South-east Norway, where winters are unstable with several freeze-thaw episodes and snowmelt events. It was noticed that soil temperatures measured in the field deviated from measurements at other stations in Ås, so the model was also tested against a limited data set from the other stations. The model performed fairly well after adjusting parameters related to snow accumulation and snow depth. It was also shown that a daily input resolution may be insufficient for simulating snow dynamics in areas with large diurnal temperature fluctuations during the winter season. Soil temperatures at the experimental site were not satisfactorily reproduced, whilst the agreement between simulations and soil temperatures from the other stations was good. The model was validated on snow depths and catchment runoff for all winters between 1995 and 2002, and in most years the model performed equally well as in 2000-01. The main problem was that small snowfall events in autumn and spring were not simulated. The melt efficiency parameters had to be reduced when simulating the cold winter 1995-96, which had continuous snow cover until spring melt. Parameter settings apparently depend on the climatic conditions. Relative errors for simulated runoff were rather large, so application of the model on catchment scale will require further adjustments/other approaches. Evidence for snowmelt infiltration was found by analysing the experimental data, and modelling indicated that this process was important during all melt events in winter 2000-01.