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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.

2020

Sammendrag

Denne rapporten presenterer naturtypekartlegging og verdisetting av naturtyper spesielt med hensyn til myr og kystlynghei innen planområdet Nylandet ved Rørvik i Vikna kommune, Trøndelag fylke, på oppdrag fra Vikna kommune.

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Sammendrag

The morphological and productive aspects of Norwegian sheep have developed over time and adapted to the diverse environment of the country. Before 1900, native Norwegian sheep were crossed with UK breeds to attain higher body weight and reproductive efficiency. Subsequent selection programs eventually led to the creation of the heavier (adults often >90 kg) Norwegian White Sheep (NWS), today constituting 70% of the recorded ewes. The modern Norwegian (White) Spæl (NS) sheep, mostly <75 kg and accounting for 10% of the recorded ewe population, originated from the native short-tailed breeds that are smaller and are believed to prefer grazing at higher altitudes than NWS. Other registered breeds of the short-tailed spæl type account for another 12% of the recorded sheep. Rugged Norwegian terrain with rich summer pastures makes the NS a complementary breed to the NWS. Increasing demand for year-round fresh meat requires changes at the farm level. Efficient use of local feed resources by extensive feeding of smaller size ewes is an opportunity for attaining economic gains and for year-round fresh meat production. The NS has a lighter bodyweight, requiring less housing space, is efficient in grazing rangeland and local pastures, and is better suited to outdoor winter grazing in coastal and fjord areas. In this paper, we compare the farm profitability (gross margin) of two Norwegian sheep breeds (NS and NWS) using a linear programming model designed for the coastal and fjord areas. The impact of ewe body weight, housing capacity, and meat produced per unit of concentrate are discussed.

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Sammendrag

By 2050, global food consumption is expected to rise by 60% compared to the 2005–2007 level. In sub-Saharan Africa (SSA), the population increase may be as much as 250% by the same period. Hence, there is an urgent need to increase food production and introduce productivity-enhancing measures in SSA agriculture, including the livestock sector, which is the main focus of this article. The current productivity of the Tanzanian livestock sector is low due to seasonal variations in the availability and quality of pasture and other feeds. The cattle gain weight during the rainy season and lose weight in the subsequent dry season. Additionally, pastoralists face challenges due to the conversion of grazing areas into cropland, overgrazing, and the increasingly frequent droughts. Although the optimum age for slaughter is 3.5–4.5 years, farmers in Tanzania slaughter their cows at 5–6 years. This article argues that this may be an unhelpful economical management practice. To study the effects of improved feeding on economic performance, we collected data on on-farm supplementation experiments with indigenous Zebu cattle, in collaboration with pastoral communities and a large-scale commercial wheat farm in Hanang, Tanzania. The study compared the income and costs associated with traditional cattle keeping (TS) for 6 years at slaughter, with that of two levels of concentrate supplementation, low (LSS) and medium (MSS), allowing for slaughtering at 4.5 and 3.5 years, respectively. Adjusted net margins for the three systems were 199, 911 and 978 USD, respectively. Our results strongly suggest that farmers should supplement the feeding of their young stock regularly, in times when the animals cannot sustain themselves on grazing alone. The primary explanations for the recommendation were that supplementation would lead to increased production of meat and reduced variable costs, that is, feeds and drugs. Our study was limited to steers. Future studies should include supplementation of cows to obtain annual calving and use of crop by-products instead of concentrates.

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Sammendrag

Norway has vast rangeland resources (292,361 km2) with an estimated carrying capacity of nearly four million sheep and lambs, twice the current number. However, the intensive production system currently applied has led to more concentrate dependency, resulting in heavier animals in addition to poorer utilization of rangelands and homegrown feed. Intensive feeding systems indirectly influence the sustainability of ecosystems by promoting intensive cropping that can deplete soil fertility and threaten landscape preservation and biodiversity. By contrast, extensive grazing systems can produce environmentally and animal-friendly food products and contribute to regulating soil health, water and nutrient cycling, soil carbon sequestration, and recreational environments. In this paper, the economics of current sheep feeding practices in Norway, using a linear programming model, were compared with more extensive systems which allow for higher usage of on-farm feed resources. Changes in current sheep farming practices have the potential to increase lamb meat production relative to mutton production, in addition to improving the year-round supply of fresh meat. The investigated alternatives, using the Norwegian White Sheep (NWS) breed, suggest that delayed lambing is useful only on farms with abundant pastures available for autumn feeding. Lambs achieve a better market price than hoggets and mature sheep. Therefore, based on the current Norwegian meat market and price offered per kilogram of meat for lamb, an increase in NWS lamb production improves farm profits. On the other hand, when the aim is on greater use of homegrown feed and rangelands, this can be achieved through hogget production, and the quantity of concentrates required can be reduced substantially.

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Sammendrag

To understand the thermal plasticity of a coastal foundation species across its latitudinal distribution, we assess physiological responses to high temperature stress in the kelp Laminaria digitata in combination with population genetic characteristics and relate heat resilience to genetic features and phylogeography. We hypothesize that populations from Arctic and cold-temperate locations are less heat resilient than populations from warm distributional edges. Using meristems of natural L. digitata populations from six locations ranging between Kongsfjorden, Spitsbergen (79°N), and Quiberon, France (47°N), we performed a common-garden heat stress experiment applying 15°C to 23°C over eight days. We assessed growth, photosynthetic quantum yield, carbon and nitrogen storage, and xanthophyll pigment contents as response traits. Population connectivity and genetic diversity were analyzed with microsatellite markers. Results from the heat stress experiment suggest that the upper temperature limit of L. digitata is nearly identical across its distribution range, but subtle differences in growth and stress responses were revealed for three populations from the species’ ecological range margins. Two populations at the species’ warm distribution limit showed higher temperature tolerance compared to other populations in growth at 19°C and recovery from 21°C (Quiberon, France), and photosynthetic quantum yield and xanthophyll pigment responses at 23°C (Helgoland, Germany). In L. digitata from the northernmost population (Spitsbergen, Norway), quantum yield indicated the highest heat sensitivity. Microsatellite genotyping revealed all sampled populations to be genetically distinct, with a strong hierarchical structure between southern and northern clades. Genetic diversity was lowest in the isolated population of the North Sea island of Helgoland and highest in Roscoff in the English Channel. All together, these results support the hypothesis of moderate local differentiation across L. digitata's European distribution, whereas effects are likely too weak to ameliorate the species’ capacity to withstand ocean warming and marine heatwaves at the southern range edge.

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Sammendrag

Potato onions (Allium cepa var aggregatum G. Don) are multiplying or aggregating onions, very similar to shallots and have been historically cultivated throughout Europe. Currently in Northern Europe they are maintained in home gardens and ex situ field collections. Potato onions are primarily vegetatively propagated, however in Estonia, near Lake Peipsi, this species has been propagated by seed since the seventeenth century. There is increasing interest in Northern Europe in utilizing this germplasm in organic and/or sustainable farming systems. The genetic diversity and relationship between and within European potato onion collections is unclear. From historical records it is known that cultivation, exchange and trade of potato onion has occurred throughout Europe for hundreds of years. This study utilised molecular markers to assess genetic diversity, duplication of genotypes and relationships among and between Nordic, Baltic, Czech and Croatian potato onion collections. Of 264 accessions, 80 catalogued as unique had identical genotypes with one or more other accessions, and are putative duplicates. The genetic diversity within two Estonian sexually propagated accessions was comparable to that found in all of the vegetatively propagated accessions. Accessions from the Nordic countries grouped together genetically, as did Latvian and Lithuanian accessions. Croatian accessions were genetically separated. These genetic relationships suggest historical movement of potato onion germplasm in North-Eastern Europe. The results, in conjunction with other passport and characterization data, can assist in the development of potato onion core collections, facilitating the conservation and utilization of valuable potato onion genetic resources.

Sammendrag

Nordmenn spiser i gjennomsnitt 6 kg løk i året. Det er lavt sammenlignet med de fleste andre land, men er likevel en økning fra ca 4 kg for 10-15 år siden. Det har blitt jobbet mye i verdikjeden for løk i Norge, med fokus på kvalitet, mangfold og kunnskapsdeling. Løk har fremfor alt god smak, men er også en av de sunneste grønnsakene. Løk anbefales spesielt som en av 5-om-dagen på grunn av sine gode dokumenterte helsevirkninger.