Publikasjoner
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.
2018
Forfattere
Marianne BechmannSammendrag
I gjennomsnitt ble det tilført 24 kg nitrogen og 7,5 kg fosfor per dekar jordbruksareal i 2016. Dette er litt over gjennomsnittet for overvåkingsperioden. Arealet med potet har økt de siste årene. Gjennomsnittlig konsentrasjon av suspendert stoff (39 mg/L) og total- fosfor (271 μg/L) var mindre enn gjennomsnittet for overvåkingsperioden, mens konsentrasjonen av løst fosfat (80 μg/L) var større enn gjennomsnittet. Gjennomsnittlig konsentrasjon av totalnitrogen var 6,7 mg/L.
Forfattere
Per-Erik Mellander Philip Jordan Marianne Bechmann Ophélie Fovet Mairead M. Shore Noeleen T. McDonald Chantal Gascuel-OdouxSammendrag
Management of agricultural diffuse pollution to water remains a challenge and is influenced by the complex interactions of rainfall-runoff pathways, soil and nutrient management, agricultural landscape heterogeneity and biogeochemical cycling in receiving water bodies. Amplified cycles of weather can also influence nutrient loss to water although they are less considered in policy reviews. Here, we present the development of climate-chemical indicators of diffuse pollution in highly monitored catchments in Western Europe. Specifically, we investigated the influences and relationships between weather processes amplified by the North Atlantic Oscillation during a sharp upward trend (2010– 2016) and the patterns of diffuse nitrate and phosphorus pollution in rivers. On an annual scale, we found correlations between local catchment-scale nutrient concentrations in rivers and the influence of larger, oceanic-scale climate patterns defined by the intensity of the North Atlantic Oscillation. These influences were catchment-specific showing positive, negative or no correlation according to a typology. Upward trends in these decadal oscillations may override positive benefits of local management in some years or indicate greater benefits in other years. Developing integrated climatechemical indicators into catchment monitoring indicators will provide a new and important contribution to water quality management objectives.
Sammendrag
Effects of mitigation measures in agriculture on abating eutrophication are difficult to evaluate by assessments of catchment monitoring data. Estimates of improved water quality by specific agricultural Best Management Practices (BMPs) are therefore often dependent on simulation modeling. A main objective was thus to assess the probable reductions in total phosphorus (TP) loading achieved by implemented agricultural mitigation measures. The case-study site was a catchment in southeastern Norway. Simulation modeling was conducted by use of The Soil and Water Assessment Tool (SWAT). The aim of this present study was to understand the model uncertainty associated both with calibration/validation (baseline) and TP loading scenarios based on BMP. The modeled decrease in TP loading by the set of implemented BMPs was assessed by comparing simulated baseline output with output where the set of abatement actions were removed. The model was set up for the years 2006–2010 and calibrated against observed monitoring data, including daily discharge, sediment- and TP fluxes. Model simulations were performed including and excluding the implemented set of mitigation measures. The simulated set of mitigation measures include decrease in amount of phosphorus fertilization, establishment of vegetated buffer strips along streams and constructed wetlands in the water courses, no autumn tilling and removal of point TP sources from scattered dwellings. Model calibration and uncertainty estimation are performed using an algorithm for Sequential Uncertainty Fitting (SUFI2; ver. 2). Probabilistic risk for given magnitudes of increased TP loading if existing BMPs were not implemented was assessed. Using this novel approach it was possible to state, with a 80th percentile confidence level, that the average annual TP loading would have been about 26% higher if no mitigation measures were implemented in the catchment. This was possible to assess even though the difference between baseline and BMP scenario was not significant.
Forfattere
Magdalena Z. Bieroza A. Louise Heathwaite Marianne Bechmann Katarina Kyllmar Philip JordanSammendrag
Recent technological breakthroughs of optical sensors and analysers have enabled matching the water quality measurement interval to the time scales of stream flow changes and led to an improved understanding of spatially and temporally heterogeneous sources and delivery pathways for many solutes and particulates. This new ability to match the chemograph with the hydrograph has promoted renewed interest in the concentration-discharge (c-q) relationship and its value in characterizing catchment storage, time lags and legacy effects for both weathering products and anthropogenic pollutants. In this paper we evaluated the stream c-q relationships for a number of water quality determinands (phosphorus, suspended sediments, nitrogen) in intensively managed agricultural catchments based on both high-frequency (sub-hourly) and long-term low-frequency (fortnightly-monthly) routine monitoring data. We used resampled high-frequency data to test the uncertainty in water quality parameters (e.g. mean, 95th percentile and load) derived from low-frequency sub-datasets. We showed that the uncertainty in water quality parameters increases with reduced sampling frequency as a function of the c-q slope. We also showed that different sources and delivery pathways control c-q relationship for different solutes and particulates. Secondly, we evaluated the variation in c-q slopes derived from the long-term low-frequency data for different determinands and catchments and showed strong chemostatic behaviour for phosphorus and nitrogen due to saturation and agricultural legacy effects. The c-q slope analysis can provide an effective tool to evaluate the current monitoring networks and the effectiveness of water management interventions. This research highlights how improved understanding of solute and particulate dynamics obtained with optical sensors and analysers can be used to understand patterns in long-term water quality time series, reduce the uncertainty in the monitoring data and to manage eutrophication in agricultural catchments.
Forfattere
Sigrun Hjalmarsdottir Kværnø Stein Turtumøygard Alexander Melvold Engebretsen Torsten StarkloffSammendrag
På oppdrag fra vannområdet Bunnefjorden med Årungen- og Gjersjøvassdraget (PURA) er den empiriske modellen Agricat 2 brukt til å beregne potensialet for erosjon og fosforavrenning fra jordbruksarealer i 16 tiltaksområder, ved faktisk drift i 2017. Arealfordelingen av faktisk drift (vekst, jordarbeiding og miljøtiltak) i 2017, har framkommet av registerdata fra Landbruksdirektoratet og føringer/informasjon fra Follo Landbrukskontor, og er fordelt på de dyrka arealene etter bestemte rutiner i modellen. Arealfordelingsrutinen i modellen ga følgende utbredelse av kombinasjon vekst/jordarbeiding i vannområdet for 2017: 31 % stubb (jordarbeiding vår eller direktesåing), 14 % gras, 38 % vårkorn med høstpløying, 4 % høstkorn med høstpløying, 10 % høstharving til vår- og høstkorn, og 3 % poteter og grønnsaker. Den største forskjellen fra 2016 var mindre høstkornareal og større areal med stubb og høstpløying med vårkorn i 2017. Arealfordelingen varierte mellom tiltaksområder. Eksisterende grasdekte buffersoner og fangdammer inngikk også i beregningene. Jord- og fosfortap i vannområdet PURA i 2017 ble beregnet til henholdsvis 4,3 kilotonn SS og 8,6 tonn TP, dvs. på samme nivå som i 2014 og 2015, og litt lavere enn i 2016. For individuelle tiltaksområder varierte jordtapet fra nær 0 til 2 kilotonn, og fosfortap fra nær 0 til knapt 4 tonn. I fem tiltaksområder var fosfortapet noe økt i 2017 sammenliknet med i 2016, i resten av tiltaksområdene var fosfortapet redusert eller tilnærmet uendret. Endret drift bidro til å forklare forskjellene.
Forfattere
Esther Bloem Annette Dathe Attila Nemes Perrine Marguerite Fernandez Helen French Matthew Patterson Daniel GiminezSammendrag
Det er ikke registrert sammendrag
Forfattere
Esther Bloem Annette Dathe Attila Nemes Perrine Marguerite Fernandez Helen French Matthew Patterson Daniel GiminezSammendrag
Det er ikke registrert sammendrag
Forfattere
Inga Greipsland Sigrun Hjalmarsdottir Kværnø Stein Turtumøygard Anne-Grete Buseth BlankenbergSammendrag
På oppdrag fra Ørland kommune har NIBIO beregnet fosforavrenning fra jordbruksarealer i nedbørfeltet og evaluert effekten av ulike tiltak ved bruk av modellen Agricat 2. Det er også beregnet avlastningsbehov for fosfor i vassdraget basert på etablerte overvåkingsstasjoner for vannkvalitet i Balsnesvassdraget. Beregningene viser at størst reduksjon oppnås ved å kombinere buffersoner langs vassdrag med redusert fosforgjødslingen over tid. Fosfortapet kan, i følge modellen, reduseres med 20 % med disse tiltakene, mens tap av partikler kan reduseres med 8 %. Det anbefales å fortsette overvåkingen av vassdraget slik at kunnskapstatus om vannkvaliteten kan bedres.
Forfattere
Roland Bol Gerard Gruau Per-Erik Mellander Rémi Dupas Marianne Bechmann Eva Skarbøvik Magdalena Bieroza Faruk Djodjic Miriam Glendell Philip Jordan Bas van der Grift Michael Rode Erik Smolders Mieke Verbeeck Sen Gu Erwin Klumpp Ina Pohle Maelle Fresne Chantal Gascuel-OdouxSammendrag
In this paper, we outline several recent insights for the priorities and challenges for future research for reducing phosphorus (P) based water eutrophication in the agricultural landscapes of Northwest Europe.We highlight that new research efforts best be focused on headwater catchments as they are a key influence on the initial chemistry of the larger river catchments, and here many management interventions are most effectively made. We emphasize the lack of understanding on how climate change will impact on P losses from agricultural landscapes. Particularly, the capability to disentangle current and future trends in P fluxes, due to climate change itself, from climate driven changes in agricultural management practices and P inputs. Knowing that, future climatic change trajectories for Western Europe will accelerate the release of the most bioavailable soil P. We stress the ambiguities created by the large varieties of sources and storage/transfer processes involved in P emissions in landscapes and the need to develop specific data treatment methods or tracers able to circumvent them, thereby helping catchment managers to identify the ultimate P sources that most contribute to diffuse P emissions. We point out that soil and aqueous P exist not only in various chemical forms, but also in range of less considered physical forms e.g., dissolved, nanoparticulate, colloidal and other particulates, all affected differently by climate as well as other environmental factors, and require bespoke mitigation measures. We support increased high resolution monitoring of headwater catchments, to not only help verify the effectiveness of catchments mitigation strategies, but also add data to further develop new water quality models (e.g., those include Fe-P interactions) which can deal with climate and land use change effects within an uncertainty framework. We finally conclude that there is a crucial need for more integrative research efforts to deal with our incomplete understanding of the mechanisms and processes associated with the identification of critical source areas, P mobilization, delivery and biogeochemical processing, as otherwise even highintensity and high-resolution research efforts will only reveal an incomplete picture of the full global impact of the terrestrial derived P on downstream aquatic and marine ecosystems.
Sammendrag
Høye P-AL-verdier i jorda utgjør en betydelig forurensningsrisiko for vann og vassdrag. Det er derfor viktig å redusere P-AL-nivået der dette er unødvendig høyt ved å gjødsle med mindre fosfor enn det som tas ut med avlingene. I følge NIBIOs gjødslingsanbefaling kan fosfor utelates på arealer med meget høye fosforverdier (P-AL >14), fordi jorda bidrar med nok fosfor til plantene. Det har vært usikkert om denne gjødslingsanbefalingen følges opp i praksis, og vi har derfor gjennomført en spørreundersøkelse blant landbruksrådgiverne. Formålet med denne spørreundersøkelsen var å avdekke flaskehalser for å utelate fosforgjødsling på arealer med meget høye fosforverdier. Spørreundersøkelsen ble sendt til landbruksrådgivere i Norsk Landbruksrådgivning (NLR). Det kom inn 96 svar...........