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
Rachel Cassidy Philip Jordan Marianne Bechmann Brian Kronvang Katarina Kyllmar Mairead ShoreSammendrag
Achieving an operational compromise between spatial coverage and temporal resolution in national scale river water quality monitoring is a major challenge for regulatory authorities, particularly where chemical concentrations are hydrologically dependent. The efficacy of flow-weighted composite sampling (FWCS) approaches for total phosphorus (TP) sampling (n = 26–52 analysed samples per year), previously applied in monitoring programmes in Norway, Sweden and Denmark, and which account for low to high flow discharges, was assessed by repeated simulated sampling on high resolution TP data. These data were collected in three research catchments in Ireland over the period 2010–13 covering a base-flow index range of 0.38 to 0.69. Comparisons of load estimates were also made with discrete (set time interval) daily and sub-daily sampling approaches (n = 365 to >1200 analysed samples per year). For all years and all sites a proxy of the Norwegian sampling approach, which is based on re-forecasting discharge for each 2-week deployment, proved most stable (median TP load estimates of 87–98%). Danish and Swedish approaches, using long-term flow records to set a flow constant, were only slightly less effective (median load estimates of 64–102% and 80–96%, respectively). Though TP load estimates over repeated iterations were more accurate using the discrete approaches, particularly the 24/7 approach (one sample every 7 h in a 24 bottle sampler - median % load estimates of 93–100%), composite load estimates were more stable, due to the integration of multiple small samples (n = 100–588) over a deployment.
Sammendrag
Over their life course, people change their consumption habits when prices, income, tastes or nutritional needs change. The time period during which an individual grew up is often reflected in his or her consumption of different types of food. To investigate the possible links between demographic changes and food consumption, we constructed two-step censored demand systems for different groups of foods. We estimated the systems using Norwegian data for the 1986 – 2012 period. In the systems, age, period, cohort, other demographic and economic variables are included. The estimated systems are used to construct a long-run forecasting model for meat and dairy products. In this model, younger cohorts replace older cohorts with a different consumption pattern. The total purchases of beef, lamb, pork and fluid milk are predicted to decrease, while the total purchases of chicken, yoghurt and cheese are predicted to increase towards 2027.
Sammendrag
The apple fruit moth Argyresthia conjugella (Lepidoptera, Yponomeutidae) is a seed predator of rowan (Sorbus aucuparia) and is distributed in Europe and Asia. In Fennoscandia (Finland, Norway and Sweden), rowan fruit production is low every 2–4 years, and apple (Malus domestica) functions as an alternative host, resulting in economic loss in apple crops in inter-mast years. We have used Illumina MiSeq sequencing to identify a set of 19 novel tetra-nucleotide short tandem repeats (STRs) in Argyresthia conjugella. Such motifs are recommended for genetic monitoring, which may help to determine the eco-evolutionary processes acting on this pest insect. The 19 STRs were optimized and amplified into five multiplex PCR reactions. We tested individuals collected from Norway and Sweden (n = 64), and detected very high genetic variation (average 13.6 alleles, He = 0.75) compared to most other Lepidoptera species studied so far. Spatial genetic differentiation was low and gene flow was high in the test populations, although two non-spatial clusters could be detected. We conclude that this set of genetic markers may be a useful resource for population genetic monitoring of this economical important insect species.
Sammendrag
Background: Generalized height-diameter curves based on a re-parameterized version of the Korf function for Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.) and silver birch (Betula pendula Roth) in Norway are presented. The Norwegian National Forest Inventory (NFI) is used as data base for estimating the model parameters. The derived models are developed to enable spatially explicit and site sensitive tree height imputation in forest inventories as well as future tree height predictions in growth and yield scenario simulations. Methods: Generalized additive mixed models (gamm) are employed to detect and quantify potentially non-linear effects of predictor variables. In doing so the quadratic mean diameter serves as longitudinal covariate since stand age, as measured in the NFI, shows only a weak correlation with a stands developmental status in Norwegian forests. Additionally the models can be locally calibrated by predicting random effects if measured height-diameter pairs are available. Based on the model selection of non-constraint models, shape constraint additive models (scam) were fit to incorporate expert knowledge and intrinsic relationships by enforcing certain effect patterns like monotonicity. Results: Model comparisons demonstrate that the shape constraints lead to only marginal differences in statistical characteristics but ensure reasonable model predictions. Under constant constraints the developed models predict increasing tree heights with decreasing altitude, increasing soil depth and increasing competition pressure of a tree. A two-dimensional spatially structured effect of UTM-coordinates accounts for the potential effects of large scale spatially correlated covariates, which were not at our disposal. The main result of modelling the spatially structured effect is lower tree height prediction for coastal sites and with increasing latitude. The quadratic mean diameter affects both the level and the slope of the height-diameter curve and both effects are positive. Conclusions: In this investigation it is assumed that model effects in additive modelling of height-diameter curves which are unfeasible and too wiggly from an expert point of view are a result of quantitatively or qualitatively limited data bases. However, this problem can be regarded not to be specific to our investigation but more general since growth and yield data that are balanced over the whole data range with respect to all combinations of predictor variables are exceptional cases. Hence, scam may provide methodological improvements in several applications by combining the flexibility of additive models with expert knowledge.
Forfattere
Gernot Bodner Arta Kronberga Liga Lepse Margit Olle Ingunn M. Vågen Lasma Rabante Juan A. Fernández Georgia Ntatsi Astrit Balliu Boris RewaldSammendrag
European pulse production faces a continued loss of cultivated area along with decreasing or stagnant yields. Vicia faba is a traditional legume with high genetic diversity cultivated in a wide range of European climates. Therefore V. faba is promising to identify stable and high yielding genotypes for specific target environments. The Nordic-Baltic region is challenging for legume growing due to short vegetation period and heat/drought stress in continental climates. Within the pan-European Eurolegume project a set of 18 V. faba accessions containing var. minor and major local landraces and modern cultivars of different geographical origin was evaluated in multi-environmental trials. The aim of this study was to identify ideotypes for Northern Europe and reveal key phenotypic traits conferring high yield potential and stability. Four target environmental clusters represented the range of Nordic growing conditions with yield levels from 128 gm−2 to 380 gm−2. Multivariate classification differentiated distinctive groups of var. minor and var. major accessions with few overlapping genotypes, the former having higher average yield, taller structure, more pods per node and longer flowering duration. Late sowing under long-day conditions above 55°N latitudes resulted in early flowering due to short vegetative development (650 °Cd). Extended flowering duration and tall stature were the most important traits conferring high yields. A negative trade-off between yield potential and yield stability was detected, with yield advantages of stress resistant genotypes only in a limited range of low yielding target environments (< 180 gm−2). The highest yielding accessions (Latvian var. minor landrace Bauska and var. major landrace Cēres) represented a favourable combination of yield potential and stability. High temperatures at flowering, within a range of average maximum July temperatures between 20.5–24.5 °C, were identified as most critical environmental variable depressing yield levels between 38.5 (var. major) and 56.2 (var. minor) gm−2 °C−1. It was concluded that Baltic landraces are promising ideotypes, with adapted flowering phenology and morphological structure, for increased V. faba yields in Nordic target environments.
Forfattere
Ingeborg Callesen Nicholas Clarke Andis Lazdinš Iveta Varnagiryte-Kabasinskiene Karsten Raulund-RasmussenSammendrag
The long-term carrying capacity for biomass production is highly dependent on available soil resources. A soil test method for potential nutrient release capability was applied to 23 Nordic and Baltic forest soil profiles. The soils had coarse (10), medium (12) and fine (1) soil texture and most were podsolising. Extraction with dilute (0.1 M, 1:50 sample:solution ratio) nitric acid for 2 h was followed by 48 h and 168 h of extraction in soil samples from pedogenetic horizons. Dilute nitric acid solution was replaced after each step and release of mineral nutrient elements in solution was determined. C-horizon nutrient release (µmol g−1 fine earth, 0–218 h) was negatively correlated with mean annual temperature (MAT 0.5–8.5 °C) and for potassium (K) also mean annual precipitation (MAP 523–1440 mm y−1) suggesting a gradient in the mineralogy of the parent material that sediment transports during Pleistocene glaciations have not distorted. In B-horizons of sandy parent materials with felsic mineralogy cumulative nutrient release was positively correlated with pH and with Al and Fe release suggesting accumulation and stabilisation of nutrients in pedogenic products. E-horizons had less nutrient release capability than C-horizons, indicating a more weathered state of E-horizon parent material. Soil formation due to mineral dissolution and leaching of base cations and the gradient in parent material origin and weathering state both affected the observed pattern of nutrient release. On soils with very low mineral P resources (e.g. < 250 kg P ha−1 to 50 cm) by repeated dilute acid extraction, harvest of nutrient rich biomass will not be sustainable. However, it can’t be concluded that sites with high P availability by 0.1 M HNO3 can support an intensive harvest without compensation of P (and Ca) by fertilisation. Due to buffering of removed base cations in B-horizons, nutrient export with biomass may not be traceable as pH decline at decadal time scale. Therefore, the direct measurement of nutrient stocks by the extraction procedure (or other similar assessment of nutrient reserves by strong acid) is suggested as indicative for the mineral weathering capability of forest soils to recover from P and base cation depletion by biomass harvest.
Forfattere
Milan Flach Sebastian Sippel Fabian Gans Ana Bastos Alexander Brenning Markus Reichstein Miguel D. MahechaSammendrag
Combined droughts and heatwaves are among those compound extreme events that induce severe impacts on the terrestrial biosphere and human health. A record breaking hot and dry compound event hit western Russia in summer 2010 (Russian heatwave, RHW). Events of this kind are relevant from a hydrometeorological perspective, but are also interesting from a biospheric point of view because of their impacts on ecosystems, e.g., reductions in the terrestrial carbon storage. Integrating both perspectives might facilitate our knowledge about the RHW. We revisit the RHW from both a biospheric and a hydrometeorological perspective. We apply a recently developed multivariate anomaly detection approach to a set of hydrometeorological variables, and then to multiple biospheric variables relevant to describe the RHW. One main finding is that the extreme event identified in the hydrometeorological variables leads to multidirectional responses in biospheric variables, e.g., positive and negative anomalies in gross primary production (GPP). In particular, the region of reduced summer ecosystem production does not match the area identified as extreme in the hydrometeorological variables. The reason is that forest-dominated ecosystems in the higher latitudes respond with unusually high productivity to the RHW. Furthermore, the RHW was preceded by an anomalously warm spring, which leads annually integrated to a partial compensation of 54% (36% in the preceding spring, 18% in summer) of the reduced GPP in southern agriculturally dominated ecosystems. Our results show that an ecosystem-specific and multivariate perspective on extreme events can reveal multiple facets of extreme events by simultaneously integrating several data streams irrespective of impact direction and the variables' domain. Our study exemplifies the need for robust multivariate analytic approaches to detect extreme events in both hydrometeorological conditions and associated biosphere responses to fully characterize the effects of extremes, including possible compensatory effects in space and time.
Sammendrag
Rapporten beskriver, og gir resultater fra, «Overvåkingsprogrammet for skog i verneområder» som omfatter nasjonalparker og naturreservater som var etablert pr. 1.1.2016. Registreringene ble gjennomført av Landsskogtakseringen i perioden 2012-2016. Statistikk for arealtyper, skogtilstand og miljøverdier som er viktig for biologisk mangfold sammenstilles. [...] Denne rapporten er en revidert utgave av NIBIO rapport 3(142) 2017, M-921. Kapittel 4.5: Volum, og tilhørende tabeller i vedlegget, er oppdatert på grunn av endring i grunnlagsdata.
Sammendrag
Antallet kunstgressbaner har økt kraftig i Norge de siste 15 årene, og det finnes per i dag 1750 kunstgressbaner i Norge. De oppmalte bildekkene og andre typer granulat fra nyprodusert industrigummi som brukes på kunstgressbaner er nå ansett som en av de største landbaserte kildene til mikroplast. Det viser seg at selv en godt driftet bane sprer granulatet i det ytre miljøet, spesielt baner med vinterdrift. I Vannområde Indre Oslofjord Vest tilsvarer dette mer enn 100 tonn granulat per år, som slippes ut i naturen. Vannområdet ba NIBIO om å ta jordprøver rundt tre av disse fotballbanene med vinterdrift for å bekrefte utlekking fra banene. Jordprøver viste at store mengder – opp til flere kg per kvadratmeter – finnes i nærheten av kunstgressbanene, og analysen av granulatet med simultan termisk analyse og Fourier-transformert infrarød spektroskopi ga oss innsyn i den kjemiske sammensetning av disse granulatpartiklene. Dette blir presentert i foredraget, samt tiltak som kan iverksettes for å redusere tap av granulat rundt kunstgressbaner.
Sammendrag
CAN THE ALERTNESS OF ICELANDIC LEADERSHEEP HELP TO PROTECT SHEEP FLOCKS AGAINST PREDATORS? Emma BRUNBERG 1), Lise GRØVA 2), Emma EYTHÓRSDÓTTIR 3), Ólafur R. DÝRMUNDSSON 4) 1) NORSØK, Norwegian Centre for Organic Agriculture, Gunnars veg 6, 6630 Tingvoll, Norway; emma.brunberg@djurskyddet.se 2) NIBIO, Norwegian Institute of Bioeconomy Research, Gunnars veg 6, 6630 Tingvoll, Norway; lise.grova@nibio.no 3) LBHÍ, Agricultural University of Iceland, Árleyni 22, 112 Reykjavík, Iceland , emma@lbhi.is 4) Jórusel 12, 109 Reykjavík, Iceland, oldyrm@gmail.com Icelandic leadersheep, a unique sub-breed of the North European short-tailed Iceland breed, are known for their strongly inherited alertness and urge to lead their flock. They have been known through centuries for their outstanding behavioural abilities and intelligence and have not been selected for production traits like other Icelandic sheep. The behavioural traits of these sheep have attracted attention; particularly their alertness and the possibility that this could play a role in protecting sheep flocks against predator attacks. Norwegian scientists have shown breed differences in sheep mortality at summer pastures due to predators. A joint Icelandic/Norwegian project was initiated to test the hypothesis that the presence of Icelandic leadersheep affects flock behaviour when exposed to a predator model. Detecting such differences can clearly be regarded as being of both economic and welfare importance. Since it was not feasible to transport Icelandic leadersheep to Norway it was decided to test their alertness in comparison with that of other sheep in Iceland. An experiment was carried out on Hestur Sheep Experimental Farm in W- Iceland during two days in November 2016 using a total of 66 ewes divided into 11 groups. Six of the groups consisted of one Icelandic leadersheep and five Icelandic sheep (LSG), the remaining five groups consisted of six Icelandic sheep (ISG). The predator model tests took place within a fenced, rectangular pasture of 50m x 25m adjacent to a sheep house. All 11 groups were exposed to the same three treatments: human-, dog- and drone test, after a 10 minutes habituation period. The order of the treatments was randomized and there was a minimum 5 minutes interval between each test. All tests were video recorded. The behaviour observations recorded were; eat, stand walk, run and „other“. Recordings were made every 5 seconds during a two-minute period before and after test period, as well as every 5 seconds in 5*30second periods during each of the human, dog and drone treatment. Statistical analyses were conducted using the GLIMMIX procedure in SAS. There was a significant difference in behaviour between the groups with LSG compared to ISG. The LSG spent significantly more time feeding than the ISG groups for all tests, especially in the period after each test was finished, and it hence seems the LSG recover more quickly after a predator test. Including an Icelandic leadersheep into the flock affects behaviour. This should be further elaborated in commercial settings in order to understand the impact and relevance of including this genetic trait in sheep farming. Keywords: sheep, behaviour, predators, Icelandic leadersheep, predator model