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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.

1999

Sammendrag

Studies were undertaken in forest ecosystems of the northwestern Kola Peninsula, Russia and South-Varanger, Norway in the zone affected by the Pechenganikel smelter. The soils consist mainly of shallow sandy iron-humus-illuvial and iron-illuvial podzols on highly bouldery unsorted morainic deposits of course texture, fluvioglacial sands and bedrocks.Plant specimens were collected from 16 plots located at different distances from the source of emissions: Pinus sylvestris needles, bark and wood, dwarf shrub (Empetrum hermaphroditum, Vaccinium myrtillus and Vaccinium vitis-idaea ) leaves, wavy-hair grass (Deschampsia flexuosa), green mosses (Hylocomium splendens and Pleurozium schreberi) and lichens (Cladina rangifirina [Cladonia rangiferina], and Cladina stellaris [Physcia stellaris]) were collected at the end of the growing season.Results showed that the elemental composition of the dominants of the tree, grass-shrub, and moss layers was affected by the sulfur and heavy metals from the source of pollution. The content of nickel and copper in pine needles near the smelter exceeded control levels by an order of magnitude and the content of sulfur exceeded it twofold, reaching toxic levels.In addition to the direct input of pollutants from the atmosphere, soil contamination by nickel and copper within a 30 km radius of the smelter will have adverse effects on mineral nutrition of plants.It is concluded that the disturbance of biological cycles because of the active involvement of pollutants and the decreased availability of nutrients results in retardation of plant growth, a reduction in forest biomass and alterations in plant succession and species composition that leads to simplification and death of forest ecosystems.

Sammendrag

Outline of the thesis Chapter 1 Introduction Chapter 2 was published in an international proceedings (French et al., 1994) at an early stage of this Ph.D work and describes the experimental field set-up at Gardermoen; instrumentation and installation procedures. As more installations have been included at the experimental site, the publication has been slightly modified to include these changes in the presented chapter. Chapter 3 evaluates the uncertainty of spatial moments calculations from a limited number of measuring points. This is done by theoretical simulations of flow and transport in a 2D model (SUTRA, Voss, 1984). Spatial moment calculations of a plume distribution based on 9000 nodes and a set up of 30 measuring points are compared and the situation for various degrees of heterogeneity of the permeability fields tested. A regular and an irregular set-up is examined. The simulations of this chapter are based on a groundwater level at 2.7 m depth which is similar to the monitored depth interval in the field (2.4 m deep). The simulations revealed that predictions of the vertical centres of mass were quite good. A larger difference between the depth of the monitored area and the depth to the groundwater, may inflict larger prediction errors of the vertical centres of mass. This point is not examined in chapter 3. An idea of what the prediction error of the vertical centre of mass might have been at the field site Moreppen, is provided from the simulation where the groundwater level is defined at the more realistic level of 4 m depth (Fig. 4, only one realisation is shown). Chapter 4 examines the heterogeneity of the snowmelt/drainage pattern at the field site and relates it to the local microtopography. The range of infiltration variation is quantified from melting plates and indirectly from breakthrough curves observed in the uppermost part of the monitoring zone. Chapter 5 compares numerical simulations of solute transport in a heterogeneous or homogeneous soil with field results performed during autumn rains and snowmelting conditions. Different combinations of heterogeneities, of infiltration and soil hydraulic conductivities are tested numerically and their relative importance is determined. Chapter 6 shows calculations of degradation rates and retardation factors on the basis of spatial moment analysis of field results. The plume evolution of a reactive and an inert chemical are compared, and the difference quantified by vertical centres of mass. Simulated development of concentration distribution is shown in figure 3. The use of average manganese concentrations as an indicator of degradation in the unsaturated zone is also evaluated.