0000000000135835
AUTHOR
ØYvind Kaste
Influence of Riverine Input on Norwegian Coastal Systems
Coastal ecosystems are of high ecological and socioeconomic importance and are strongly influenced by processes from land, sea, and human activities. In this study, we present physical, chemical, and biological observations over two consecutive years from three study regions along the Norwegian coast that represent a broad latitudinal gradient in catchment and oceanographic conditions (∼59–69°N): outer Oslofjord/southern Norway, Runde/western Norway, and Malangen/northern Norway. The observations included river monitoring, coastal monitoring, and sensor-equipped ships of opportunity (“FerryBox”). The riverine discharge and transports were an order of magnitude higher, and the spatiotemporal…
Organic nitrogen steadily increasing in Norwegian rivers draining to the Skagerrak coast
AbstractDeclining atmospheric nitrogen (N) deposition, through reduction in the direct input of inorganic N, may result in less inorganic N being leached from soils to freshwaters (dissolved inorganic N = DIN). Declining sulphur deposition, through reducing the ionic strength in soil water, increases the solubility and mobility of organic soil compounds and may result in increased leaching of organically bound N to freshwaters (total organic N = TON). It is unknown to which extent these two independents and opposing trends, i.e. DIN decline versus TON increase, may affect the nutrient balance (load, stoichiometry) of river water draining into coastal zones. By combining long-term atmospheri…
Climate mitigation and intensified forest management in Norway: To what extent are surface waters safeguarded?
AbstractWhile the role of forestry in mitigating climate change is increasingly subject to political commitment, other areas, such as water protection, may be at risk. In this study, we ask whether surface waters are sufficiently safeguarded in relation to the 2015 launch of a series of measures to intensify forest management for mitigation of climate change in Norway. First, we assess how impacts on water are accounted for in existing regulations for sustainable forestry. Secondly, we provide an overview of the impacts of forestry on water quality relevant to three support schemes: afforestation on new areas, increased stocking density in existing forests, and forest fertilisation. Lastly,…
Intensified forestry as a climate mitigation measure alters surface water quality in low intensity managed forests
Climate change has led to a focus on forest management techniques to increase carbon (C) sequestration as a mitigation measure. Fertilisation and increased removal of biomass have been proposed. But these and other forest practices may have undesirable effects on surface water quality. In naturally acid-sensitive areas such as much of Fennoscandia a concern is acidification due to acid deposition in combination with forest practices that increase the removal of base cations and leaching of nitrate (NO3). Here we apply the biogeochemical model MAGIC to the coniferous-forested catchment at Birkenes, southernmost Norway, to simulate the effects of forest fertilisation and harvest on soil and s…
Mulighetskartlegging for kystbaserte næringer i Agder
I Agder er det et sterkt ønske fra kystkommunene om å tilrettelegge for blå vekst i regionen, men for å realisere dette målet er det behov for faktisk kunnskap om hvilke muligheter havet gir – og utelukker – langs hele Agder-kysten. En slik kartlegging vil være et viktig beslutningsgrunnlag for utvikling av næring knyttet til marin sektor i regionen. Dette danner bakgrunnen for prosjektet «Mulighetskartlegging for kystbaserte næringer i Agder» som er gjennomført i samarbeid mellom NIVA og Havforskningsinstituttet. Målet med prosjektet har vært å (1) Kartlegge naturgitte næringsmuligheter innenfor marin sektor langs Agderkysten, (2) Formidle kunnskap om hvilke muligheter havet gir – og utelu…
Potential impacts of a future Nordic bioeconomy on surface water quality
AbstractNordic water bodies face multiple stressors due to human activities, generating diffuse loading and climate change. The ‘green shift’ towards a bio-based economy poses new demands and increased pressure on the environment. Bioeconomy-related pressures consist primarily of more intensive land management to maximise production of biomass. These activities can add considerable nutrient and sediment loads to receiving waters, posing a threat to ecosystem services and good ecological status of surface waters. The potential threats of climate change and the ‘green shift’ highlight the need for improved understanding of catchment-scale water and element fluxes. Here, we assess possible bio…
Streamwater responses to reduced nitrogen deposition at four small upland catchments in Norway
AbstractReduced emissions of nitrogen (N) in Europe have resulted in decreasing atmospheric deposition since 1990. Long-term data (1988–2017) from four small Norwegian catchments located along gradients in N deposition, rainfall, and organic carbon (C) show different responses to 25–30% reductions in N deposition during the same period. At three sites the decreased N deposition caused reduced leaching of nitrate to surface water, whereas the westernmost site showed no decrease, probably due to thin soils with low C:N ratio, poor vegetation cover and high precipitation. The loss of total N to streamwater constituted 30–50% of the N deposition. Losses via denitrification are unknown but assum…