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
Sammendrag
Pærevisnesjuke regnes som en av de mest alvorlige sjukdommene på pære. Pærevisnesjuke forårsakes av fytoplasma, små veggløse bakterier som lever i silvevet i planter Dette er en karanteneskadegjører i Norge som ble påvist her i landet for første gang i 2015. I 2016 og 2017 ble det gjenomført et OK-program for denne skadegjøreren. Det ble totalt analysert 853 prøver i OK-programmet i 2016. Det ble totalt påvist pærevisnesjuke i 72 av prøvene. Det ble påvist pærevisnesjuke i 10 av 44 undersøkte frukthager. I 2017 ble det undersøkt 260 prøver fra 14 lokaliteter i fire fylker. Det påvist pærevisnesjuke i 13 prøver fra to lokaliteter.I 2017 ble også innsamlede sugere testet for pærevisnesjuke. Av i alt 304 individer fra 6 lokaliteter var 21 individer fra to lokaliteter infisert.
Sammendrag
Sewage sludge is a significant phosphorus resource that should be better utilized in the plant production than today. However, phosphorus in sludge produced after precipitation with aluminium and iron coagulants have low plant availability. This article presents results from plant growth experiments where plant available phosphorus in lime precipitated sewage sludge from Bokerøya and Skådevika wastewater treatment plants was studied. Both wastewater treatment plants normally use iron as coagulant aid, but Skådevika produced in addition a sludge to the experiments without using iron. The growth experiments included a pot experiment in greenhouse with three harvests of Italian ryegrass (Lolium multiflorum) and a two-year field experiment in cereals in Southeast Norway. The results showed that precipitation with lime gives a sludge with higher plant availability of phosphorus than what is earlier found for aluminium/ iron precipitated sludge. This was special the case with moderate use of iron as coagulant aid.
Sammendrag
This paper compares technical efficiencies (TEs) and technological gap ratios (TGRs) for dairy farms in regions of Norway, accounting for differences in working environments. We used the state-of-the-art stochastic meta-frontier approach to estimate TEs and TGRs to account for regional heterogeneity, and the ‘true’ random-effect model to account for farm effects. The dataset used was farm-level balanced panel data for 24 years (1992–2014), with 5442 observations from 731 dairy farms. The results of the analysis provide empirical evidence of small regional differences in TEs, TGRs, and input use. Furthermore, the results may provide support for the more regionally specific agricultural policy, in terms of support schemes and structural regulations.
Forfattere
Per VesterbuktSammendrag
Rapporten inneholder revidering av fire skjøtselsplaner for verdifulle slåttemarker på Flåøya i Sunndal kommune, Møre og Romsdal Fylke. Slåttemarkene er; BN00068533 Flåøya 1, BN00068532 Flåøya 2, BN00068530 Flåøya 3, BN00068531 Flåøya 4. Samtlige lokaliteter innehar artsrike slåttemarker med god hevd og verdi A. Slåttemarkene utgjør også habitat for rødlistearten stor bloddråpesvermer (EN – Sterkt truet). I tillegg opprettholder engene et kulturlandskap langs Sunndalsfjorden som gir en landskapsverdi. Det er avgjørende med en videreføring av tradisjonell ekstensiv skjøtsel for å kunne opprettholde verdien på disse slåttemarkene.
Forfattere
Per VesterbuktSammendrag
Rapporten inneholder revidering av tre skjøtselsplaner for verdifulle slåttemarker på Fremste Kilsti i Norddal kommune, Møre og Romsdal Fylke. Slåttemarkene er; 1. Eidsdal: Kilsti, Elveteigen. 2. Eidsdal: Kilsti, Elveteigen øvst. 3. Eidsdal: Kilsti, Rabbane. Samtlige lokaliteter innehar artsrike slåttemarker med god hevd og verdi A. Samtidig inngår de i et helhetlig kulturlandskap med både nedlagte og aktive fjell- og fjordgårder langs Storfjorden og har i tillegg til verdien av slåttemarka stor landskapsverdi. Det er avgjørende at den tradisjonelle ekstensive skjøtsel videreføres hvis man skal kunne opprettholde verdien på disse slåttemarkene.
Forfattere
Therese With BergeSammendrag
Det er ikke registrert sammendrag
Sammendrag
Utarbeiding av skjøtselsplanen for Holandsosen naturreservat har blitt gjennomført på oppdrag fra Vega verneområdestyre på vegne av grunneiere og beitebrukere. Skjøtselsplanen er en revidering av planen fra 2007 og gir faglig funderte anbefalinger for videre skjøtsel av kystlynghei og andre viktige naturtyper i Holandsosen naturreservat i Vega kommune. De viktigste tiltak som anbefales i denne planen for å ivareta kulturlandskapsverdiene og biologisk mangfold i Holandsosen naturreservat er å fortsette med sauebeiting og opprettholde beitetrykket slik det har vært de siste årene, samt å fortsette å svi kystlynghei i tråd med gjeldende sviplan. I tillegg bør bjørkeoppslaget tynnes i enkelte områder der bjørka opptrer som en gjengroingstrussel og å fjerne oppslag av buskfuru og spredte trær av sitkagran og buskfuru. To nye naturbaselokaliteter har blitt registrert i forbindelse med feltarbeidet til denne skjøtselsplanen.
Forfattere
Ari Hietala Isabella Børja Hugh Cross Nina Elisabeth Nagy Halvor Solheim Volkmar Timmermann Adam Vivian-SmithSammendrag
European ash (Fraxinus excelsior), a keystone species with wide distribution and habitat range in Europe, is threatened at a continental scale by an invasive alien ascomycete, Hymenoscyphus fraxineus. In its native range of Asia, this fungus is a leaf endophyte with weak parasitic capacity and robust saprobic competence in local ash species that are closely related to European ash. In European ash, H. fraxineus has a similar functional role as in Asia, but the fungus also aggressively kills shoots, resulting in crown dieback and tree death. H. fraxineus is a typical invasive species, as its spread relies on high propagule pressure. While crown dieback of European ash is the most obvious symptom of ash dieback, the annual colonization of ash leaves is a crucial key dependency for the invasiveness of H. fraxineus, since its fruiting bodies are formed on overwintered leaf vein tissues in soil debris. Leaves of European ash host a wide range of indigenous epiphytes, endophytes, facultative parasites and biotrophic fungi, including Hymenoscyphus albidus, a relative of H. fraxineus that competes for the same sporulation niche as the invader. At face value, leaves of European ash are colonized by a large and diverse indigenous mycobiome. In order to understand why this invader became successful in Europe, we discuss and summarize the current knowledge of diversity, seasonal dynamics and traits of H. fraxineus and indigenous fungi associated with leaves of European ash.
Forfattere
Donghai Wu Philippe Ciais Nicolas Viovy Alan K. Knapp Kevin Wilcox Michael Bahn Melinda D. Smith Sara Vicca Simone Fatichi Jakob Zscheischler Yue He Xiangyi Li Akihito Ito Almuth Arneth Anna Harper Anna Ukkola Athanasios Paschalis Benjamin Poulter Changhui Peng Daniel Ricciuto David Reinthaler Guangsheng Chen Hanqin Tian Helene Genet Jiafu Mao Johannes Ingrisch Julia E.S.M. Nabel Julia Pongratz Lena R. Boysen Markus Kautz Michael Schmitt Patrick Meir Qiuan Zhu Roland Hasibeder Sebastian Sippel Shree R.S. Dangal Stephen Sitch Xiaoying Shi Yingping Wang Yiqi Luo Yongwen Liu Shilong PiaoSammendrag
Field measurements of aboveground net primary productivity (ANPP) in temperate grasslands suggest that both positive and negative asymmetric responses to changes in precipitation (P) may occur. Under normal range of precipitation variability, wet years typically result in ANPP gains being larger than ANPP declines in dry years (positive asymmetry), whereas increases in ANPP are lower in magnitude in extreme wet years compared to reductions during extreme drought (negative asymmetry). Whether the current generation of ecosystem models with a coupled carbon– water system in grasslands are capable of simulating these asymmetric ANPP responses is an unresolved question. In this study, we evaluated the simulated responses of temperate grassland primary productivity to scenarios of altered precipitation with 14 ecosystem models at three sites: Shortgrass steppe (SGS), Konza Prairie (KNZ) and Stubai Valley meadow (STU), spanning a rainfall gradient from dry to moist. We found that (1) the spatial slopes derived from modeled primary productivity and precipitation across sites were steeper than the temporal slopes obtained from interannual variations, which was consistent with empirical data; (2) the asymmetry of the responses of modeled primary productivity under normal inter-annual precipitation variability differed among models, and the mean of the model ensemble suggested a negative asymmetry across the three sites, which was contrary to empirical evidence based on filed observations; (3) the mean sensitivity of modeled productivity to rainfall suggested greater negative response with reduced precipitation than positive response to an increased precipitation under extreme conditions at the three sites; and (4) gross primary productivity (GPP), net primary productivity (NPP), aboveground NPP (ANPP) and belowground NPP (BNPP) all showed concave-down nonlinear responses to altered precipitation in all the models, but with different curvatures and mean values. Our results indicated that most models overestimate the negative drought effects and/or underestimate the positive effects of increased precipitation on primary productivity under normal climate conditions, highlighting the need for improving eco-hydrological processes in those models in the future.
Sammendrag
Beta-keratin in poultry feathers is a structural protein that is resistant to degradation due to disulfide and hydrogen bonds. Feather meal can be a valuable feed compound if the digestibility can be increased. The objective of the present study was to analyze the effects of chemical, enzymatic, and pressure-thermic treatments for chicken feathers on solubility, in vitro protein digestibility (IVPD), and amino acid composition of solubilized and residual fractions. Two experiments were conducted. In experiment 1, models for solubility and IVPD were developed including the above factors applying a central composite face-centered design. Addition of sodium hydroxide (NaOH) and sodium sulfite (Na2SO3), and autoclaving time affected solubility and IVPD of the feather hydrolysates, but not addition of keratinolytic enzyme. In experiment 2, 7 combinations of the hydrolysis factors NaOH, Na2SO3, and autoclaving time with a predicted IVPD of 900 g/kg of DM, calculated for the sum of solubilized and residual feather fractions, were included to measure effects on IVPD and amino acid composition in each fraction. The IVPD values were higher for solubilized than residual fractions when treated with NaOH and autoclaving, but no differences were found when treated with Na2SO3 and autoclaving. Losses of cystine were substantial for all treatments, but lower for Na2SO3 than for NaOH. Furthermore, use of lower Na2SO3 concentration and longer autoclaving time reduced losses of cystine. Compared with NaOH treatments, Na2SO3 gave lower losses of threonine, arginine, serine, and tyrosine. With reference to the ideal protein profile for Atlantic salmon (Salmo salar L.), the treatments with 60 or 90 min autoclaving and 0.36 or 0.21% Na2SO3 had the highest chemical scores. The scores were generally higher for amino acids in residual than solubilized fractions, but with 90 min autoclaving and 0.21% Na2SO3 differences were small. In conclusion, hydrolysis of chicken feathers with low concentrations of Na2SO3 combined with autoclaving results in feather meal with high nutritional value for Atlantic salmon; separation of solubilized and residual fractions is not necessary.