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.
2016
Forfattere
Inger HansenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Beitesesongen 2016 ble det gjennomført en tapsundersøkelse i tre sauebesetninger tilhørende Nykirke beitelag i Modum kommune. Formålet med prosjektet var å kartlegge dødsårsaker hos sau i et tapsutsatt skogsbeite, med hovedfokus på lammetap. Totalt inngikk 335 søyer og 584 lam i undersøkelsen, hvorav 230 lam og 76 søyer var instrumenterte med mortalitetssendere. Statens naturoppsyn (SNO) og Veterinærinstituttet i Oslo (VI) bistod til å dokumentere dødsårsak. Førtitre av de totalt 230 radiomerkede lammene omkom på beite (18,7 %). Trettifem av disse ble gjenfunnet. SNO vurderte 33 av kadavrene med mortalitetssendere og VI undersøkte seks........
Sammendrag
Stadig flere nordmenn bor og jobber i byer og tettsteder. Behovet for nye bygninger er derfor stort, noe som medfører at grønne områder her er under konstant utbyggingspress. Samtidig har slike områder flere viktige funksjoner som ofte oversees i areal- og utbyggingsprosesser.
Forfattere
Jutta Kapfer Radim Hédl Gerald Jurasinski Martin Kopecký Fride Høistad Schei John-Arvid GrytnesSammendrag
Background: Resurveying historical vegetation plots has become more and more popular in recent years as it provides a unique opportunity to estimate vegetation and environmental changes over the past decades. Most historical plots, however, are not permanentlymarked and uncertainty in plot location, in addition to observer bias and seasonal bias, may add significant errors to temporal change. These errorsmay havemajor implications for the reliability of studies on long-term environmental change and deserve closer attention of vegetation ecologists. Methods: Vegetation data obtained from the resurveying of non-permanently marked plots are assessed for their potential to study environmental change effects on plant communities and the challenges the use of such data have to meet. We describe the properties of vegetation resurveys, distinguishing basic types of plots according to relocation error, and we highlight the potential of such data types for studying vegetation dynamics and their drivers. Finally, we summarize the challenges and limitations of resurveying non-permanently marked vegetation plots for different purposes in environmental change research. Results and conclusions: Re-sampling error is caused by three main independent sources of error: error caused by plot relocation, observer bias and seasonality bias. For relocation error, vegetation plots can be divided into permanent and non-permanent plots, while the latter are further divided into quasi-permanent (with approximate relocation) and non-traceable (with random relocation within a sampled area) plots. To reduce the inherent sources of error in resurvey data, the following precautions should be followed: (i) resurvey historical vegetation plots whose approximate plot location within a study area is known; (ii) consider all information available from historical studies in order to keep plot relocation errors low; (iii) resurvey at times of the year when vegetation development is comparable to the historical survey to control for seasonal variability in vegetation; (iv) retain a high level of experience of the observers to keep observer bias low; and (v) edit and standardize data sets before analyses.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
NIBIO har på oppdrag av Ringsaker kommune utført taksering av elgbeite i de skogkledde delene av kommunen i juni/juli 2016. Dette er en oppfølging av tilsvarende takst utført i 2015, med formål å kunne si noe om beiteproduksjon og beitepress på de enkelte jaktvald. NIBIO understreker at slike tall må brukes med forsiktighet på valdnivå, både fordi antall takstflater er få per vald og fordi det er ukjent i hvor stor grad elgens områdebruk følger valdgrenser. Tilbudet av buskbeite (lauv og furu) er lavt i alle vald sammenliknet med Østlandet for øvrig (listet fra størst til minst skuddproduksjon: Veldre, Furnes, Brøttum, RJFO, Nes), mens dekningen av beiteplanter i feltsjiktet følger Østlandet. Beitepresset (andel vinterbeita skudd) er også høyt i alle vald (listet fra størst til minst beitepress: RJFO, Veldre, Nes, Brøttum, Furnes), og trolig over de fleste planteartenes tålegrense.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Large areas of cultivated grasslands are annually abandoned and no longer used for production in Norway. Such areas will over time be encroached by shrubs and trees. Knowing that access to spring and autumn pastures is a limiting factor for sheep farmers, we tested the effect of grazing abandoned grassland on sheep production. We also assessed herbage production by looking at plant community development, pasture production, herbage quality and pasture utilization by sheep and heifers. The experiment was run for two consecutive years; 2014 and 2015. The sheep production was assessed by studying one sheep flock with 83(88) ewes(lambs) in 2014 and 77(106) ewes(lambs) in 2015, which was assigned each year with respect to age of ewe and number of lambs born to three treatments: 1) control; common farm procedure with short spring grazing period before summer grazing on range pasture, 2) spring extended; 4 weeks extended spring grazing period on abandoned cultivated grassland before summer grazing on range pasture, 3) whole season grazing on abandoned grassland. Assessment of herbage production was done by sheep grazing the whole area for one month in spring and autumn. During the summer, the area was assigned to three replicated treatments: a) control with no management, b) grazing heifers and c) grazing sheep with offspring. The stocking rate was 1.8 LU/ha, in both b and c, for a duration of one month. Pasture production and herbage intake was estimated using grazing exclosure cages. Weight gain from birth to autumn as well as slaughter weight were significantly (P<0.05) higher in lambs assigned to treatment 2 with four weeks extended spring grazing period (259 g/day and 15.7 kg) compared to treatment 1 (238 g/day and 14.3 kg) and treatment 3 (216 g/day and 13.2 kg). Herbage consumed during the summer period was on average 211 g DM/m2 and the pasture utilization was 55%. The annual consumption and utilization was 336 g DM/m2 and 62% in the grazed treatments and 28 g DM/m2 and 15% in the control, respectively. Total annual pasture production was on average 72% higher in the grazed treatments compared to the control. There was no difference between the grazed treatments on annual herbage production, herbage intake or pasture utilization. The use of abandoned cultivated grassland for extended spring grazing improved weight gain and slaughter weight of lambs. Further, grazing stimulated herbage production