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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.

2023

Sammendrag

Rapporten gir en oversikt over resultater fra dataanalyse over store og ekstreme avrenningsepisoder fra fire felt i JOVA-programmet; Mørdre, Skuterud,Time og Vasshaglona overvåkingsfelt. De representerer ulike jordbruksproduksjoner i ulike regioner. Det er analysert for nedbør, avrenning, tap av partikler, total nitrogen og fosfor. Dokumentasjonen av slike store hendelser kan brukes som del av kunnskapsgrunnlag for vurdering av behov for tiltak. Behov for tiltak er diskutert på webinar med ulike brukergrupper. Se utvidet sammendrag.

Sammendrag

Livestock husbandry has raised enormous environmental concerns around the world, including water quality issues. Yet there is a need to document long-term water quality trends in livestock-intensive regions and reveal the drivers for the trends based on detailed catchment monitoring. Here, we assessed the concentration and load trends of dissolved reactive phosphorus (DRP) in streamwater of a livestock-intensive catchment in southwestern Norway, based on continuous flow measurements and flow-proportional composite water sampling. Precipitation and catchment-level soil P balance were monitored to examine the drivers. At the field level, moreover, the relationship between soil P balance and soil test P (measured using the ammonium lactate extraction method, P-AL) was assessed. Results showed that on average of 20 years 95 % of the P was applied to the catchment during March–August, when 40 % of annual precipitation and 25 % of annual discharge occurred. The low runoff helped reduce P loss following P applications. However, flow-weighted annual mean DRP concentration significantly increased with increasingly cumulative soil P surplus (R2 = 0.55, p = 0.0002). With a mean annual P surplus of 8.8 kg ha−1, the annual mean DRP concentration (range: 49–140 μg L−1; mean: 80 μg L−1) and annual DRP load (range: 0.35–1.46 kg ha−1; mean: 0.65 kg ha−1) significantly increased over the 20-year monitoring period (p = 0.001 and 0.0003, respectively). At the field level, P-AL concentrations were positively correlated with soil P balances (R2 = 0.48, p < 0.0001), confirming the long-term impact of P balances on the risks of P loss. The study highlights the predominant role of long-term P balances in affecting DRP loss in livestock-intensive regions through the effect on soil test P.

Sammendrag

Formålet med denne rapporten er å gi en metodebeskrivelse med oppsummering av resultater for ti faktaark (vedlegg til denne rapporten), ett for hver av nedbørfeltene: (1) Borrevannet, (2) ‘Storelva, Dalselva og Undrumsdal’, (3) Merkedamselva, (4) Byfjorden, Vellebekken og Søndre Slagen, (5)Færder, (6)Akersvannet, (7) Vårnesbekken, Rovebekken, Unnebergsbekken og Haslebekken, (8) Istrevassdraget - Ula, (9) Vikfjord og (10) Brunlanes. Tilførsler av totalfosfor til elvene er dominert av arealavrenning fra jordbruksarealer og utslipp fra avløp. Tiltak som vil ha umiddelbar effekt på tilførslene omfatter blant annet oppgradering av private avløpsanlegg, overvintring i stubb på jordbruksarealer, grasdekte vannveier og kantsoner, og etablering av fangdammer. På lengre sikt er redusert gjødsling med fosfor også et viktig tiltak.

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Sammendrag

Soil health assessments that integrate physical, chemical and biological indicators help the evaluation of soil functioning, provide a framework for monitoring soil degradation, guide land management activities and secure the delivery of soil ecosystem services. In this study, we assessed soil health by soil texture class on arable land in Southeast Norway and mid-Norway and between grassland and arable land in mid-Norway. We used descriptive statistics and the Welch t-test with unequal variance and Bonferroni corrections to compare a physical soil indicator (bulk density) and chemical indicators (organic matter, P-AL, K-AL, Ca-AL, Mg-AL, Na-AL and pH). We developed scoring curves from cumulative normal distribution functions on regional soil data for various soil indicators where climate, soil texture class and land use were considered. Our results show that for certain soil texture classes, average soil indicator values differed between pedo-climatic zones on arable land, but for others the difference was not significant. The variability between the pedo-climatic zones for these can be neglected, but for the ones that differ, the variability is important to consider when assessing soil health. Similarly, this was the case when comparing land use (grassland and arable land) for most soil indicators in mid-Norway. This finding illustrates the importance of addressing unique local conditions in soil health assessments. We propose aggregating similar soil texture classes where no differences are apparent when developing scoring curves. The sub-optimal levels of plant available nutrients (P-AL and K-AL) found in the soil in both pedo-climatic zones highlights the importance of suitable threshold values for targeted soil ecosystem services to ensure soil health and sustainable agricultural production. We also recommend prioritizing the most relevant soil ecosystem services to limit the number of soil indicators that need monitoring.