0000000000135840
AUTHOR
Helene Frigstad
showing 4 related works from this author
Influence of Riverine Input on Norwegian Coastal Systems
2020
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
2020
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…
Reevaluating the Role of Organic Matter Sources for Coastal Eutrophication, Oligotrophication, and Ecosystem Health
2019
Organic matter (OM) in aquatic systems is either produced internally (autochthonous OM) or delivered from the terrestrial environment (ter-OM). For eutrophication (or the reverse – oligotrophication), the amount of autochthonous OM plays a key role for coastal ecosystem health. However, the influence of ter-OM on eutrophication or oligotrophication processes of coastal ecosystems is largely unclear. Therefore, ter-OM, or ter-OM proxies are currently not included in most policies or monitoring programs on eutrophication. Nevertheless, ter-OM is increasingly recognized as a strong driver of aquatic productivity: By influencing underwater light conditions and nutrient- and carbon availability,…
Mulighetskartlegging for kystbaserte næringer i Agder
2017
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…