250 research outputs found
Erfaringer, lønnsomhet og muligheter knyttet til bruk av fornybar energi til korntørking
Tørking av korn er en energikrevende prosess som krever høy effekt i en kort periode. Korntørking på gårdsnivå i Norge baserer seg i stor grad på bruk av fossil energi. For at landbruket skal klare å innfri sine mål om reduksjon av klimagassutslipp, vil det være nødvendig å øke andelen fornybar energi til korntørking. Men er det lønnsomt? Og hvordan er erfaringen til gårdbrukere som allerede tørker korn med fornybar energi? Oppgavens hovedproblemstilling lyder slik:
Erfaringer, lønnsomhet og muligheter knyttet til bruk av fornybar energi til korntørking
Metoden som benyttes for å besvare problemstillingen er en kvantitativ tverrsnittsundersøkelse i form av en spørreundersøkelse. Gårdbrukere med gårdsvarmeanlegg med og uten korntørke danner grunnlaget for datainnsamlingen. Ut fra deres erfaringer vurderes lønnsomheten ved å tørke korn fra ulike fornybare energibærere.
Resultatene fra undersøkelsen viser at gruppen som i dag benytter fornybar energi til korntørking er fordelt mellom små, mellomstore og store kornprodusenter. Flis er det vanligste brenselet til korntørking. Gårdsvarmeanleggene som er analysert har høye investeringskostnader, men lave brensel- og driftskostnader. Dette kombinert med flere varmeforbrukere på gården sikrer i stor grad lønnsomhet ved tørking av korn ved hjelp av gårdsvarmeanlegg. Av alle brenseltypene som er analysert er det halm som har den laveste kostnaden sett over levetiden, med en LCOE på 0,59 kr/kWh i gjennomsnitt. Flis og ved har en LCOE på henholdsvis 1,14 kr/kWh og 2,63 kr/kWh for anlegg som benyttes til korntørking. Halmfyring er gir også mest effekt per investert krone. Innehaverne av korntørke som fortsatt bruker fossilt brensel ønsker seg primært mer investeringsmidler og mer kunnskap om mulighetene for å benytte fornybar energi til korntørking.
Med bakgrunn i resultatene konkluderes det med at korntørking med bruk av fornybar energi kan være en lønnsom og miljøvennlig form for korntørking. Det er mulig å benytte fornybar energi i både nye og gamle, små og store korntørkeanlegg.To dry grain is a process which demands high effect of energy in short periods of time. In Norway, farmers usually use fossil energy to dry their grain. It is necessary to increase the use of renewable energy to be able to lower the level of emissions of greenhouse gasses. But is it cost-effective? What are the experiences of the farmers that already use renewable energy to dry grain? My thesis is as following:
Farmers’ Experiences, Cost-effectiveness and Possibilities Related to the Use of Renewable Energy in the Process of Drying Grain.
The results from the survey show that the group of farmers that use renewable energy to dry grain now, produce grain at small, medium, and large farms. When using renewable energy, woodchips is the most common fuel to use to dry grain. The analysis of the heating plants/installations at farms, show that investment costs are high, but the fuel- and operating costs are low. The combination of different areas of use secures a prominent level of cost-effectiveness when drying grain. The analysis of types of fuels proves that it is straw that has the lowest cost during the installation’s lifespan, with a LCOE of 0.59kr/kWh at an average. Woodchip and regular wood have a LCOE of 1.14kr/kWh and 2.63kr/kWh respectively when used in drying grain. The owners of grain dryers who still use fossil fuel, primarily want more investment funds and more knowledge about the options of using renewable energy in drying grain.
The conclusion, based on the results from the survey, is that drying grain by using some kind of renewable energy may be cost-effective and environmentally friendly. It is possible to use renewable energy in both new and old, and small and big grain dryers
The Development of a Row of Tines in Front of the Levelling Board on the Globus GRS 540 CR Roller
Antall dekar dyrkbar jord i Norge synker for hvert år som går, samtidig som innbyggertallet stadig øker. For at landbruket skal innfri det politiske målet om økt selvforsyning, betyr dette at avlingene må økes på eksisterende areal. Et punkt i økte avlinger er god og riktig jordbearbeiding. Tradisjonell jordbearbeiding der jorda vendes ved hjelp av plog er mest gjeldende i dagens norske jordbruk. Som sekundær jordbearbeiding, etter plogen, benyttes mange ulike redskaper. Et av disse redskapene er trommel med lamellslodd. Under gode forhold kan redskapet oppnå ferdig såbed ved én overkjøring. Det viser seg derimot at denne redskapen har ulike utfordringer under mindre gunstige vær- og jordforhold. Oppgavens problemstilling lyder derfor slik: Vil et ekstra arbeidsorgan på trommel med lamellslodd gjøre en bedre og mer effektiv bearbeidelse av pløgsla for å sikre et bedre såbed? Oppgaven tar utgangspunkt i Globus AS sin GRS CR 540 trommel med lamellslodd. Innledende tindeteori, konstruksjon av forsøksrigg, gjennomføring av feltforsøk og vurdering av ulike alternativer legger grunnlaget for sluttresultatet som konstrueres ved hjelp av dataassistert konstruksjon. Det konkluderes med at et ekstra arbeidsorgan i form av tinderekke foran lamellslodden definitivt har en funksjon og at sluttproduktet kan gi et bedre resultat enn dagens trommel med kun lamellslodd.The number of acres of arable land in Norway decreases every year, while the population continues to increase. In order to meet the political policy of increased self-sufficiency, this means that crops must be increased on existing areas. One way to obtain increased crops is good and proper tillage. The conventional tillage system where the soil is turned by plough is most common in today's Norwegian agriculture. In a secondary tillage, after the plough, many different tillage implements may be used. When the conditions are suitable the roller with the levelling board may make a seedbed in just one operation. However, it proves that this equipment may cause problems when the weather- and tillage conditions are not optimal. My thesis is therefore the following: Will a row of tines added to a roller with levelling board make a better and more efficient tillage of the plough furrow in order to make a better seedbed? The task is based on the Globus AS's GRS CR 540 roller with levelling board. An introduction of alternative tines, the construction of the experimental rig, the field experiments and finally an evaluation of the results. These results made it possible to construct a functional tillage organ by using computer- aided construction program. The field experiments show that to add a row of tines in front of the levelling board clearly give a better seedbed than just the roller with the levelling board
Low-frequency Pliocene climate variability in the eastern Nordic Seas
The Pliocene (5.3–2.6 Ma) is often described as a relatively stable climatic period, with warm temperatures characterizing high latitudes. New suborbital resolved stable isotope records from ODP Hole 642B in the Eastern Nordic Seas document that the Pliocene was not a stable period characterized by one climate. Rather, seven distinct climate phases, each lasting between 150,000 and 400,000 years, are identified and characterized in the time interval 5.1–3.1 Ma. Four of the transitions between the defined climate phases occurred close to an eccentricity minimum and a minimum in amplitude of change for Northern Hemisphere summer insolation, while two occurred around an eccentricity maximum and a maximum in amplitude in insolation change. Hence, a low frequency response of the Nordic Seas to insolation forcing is indicated. In addition, paleogeographic and related paleoceanographic changes, expansion of the Arctic sea ice cover and onset of NHG were important factors behind the evolving Pliocene low frequency variability in the eastern Nordic Seas. It is likely that the identified climate phases and transitions are important beyond the Nordic Seas, due to their association with changes to both insolation and paleogeography. Also, a strong and variable degree of diagenetic calcite overgrowth is documented for the planktic foraminifera, especially influencing the planktic δ18O results; the absolute values and amplitude of change cannot be taken at face value
Sea surface temperature variability in the Norwegian Sea during the late Pliocene linked to subpolar gyre strength and radiative forcing
Landskapet som historieforteller - Driftavegen gjennom Viglesdalen: Besøksopplevelse og lokalsamfunnsutvikling
Det er i moderne tid at menneskeskapte inngrep har omformet og
endret landskap og naturmiljø så fundamentalt. Kulturminner, -miljø
og landskap er en ikke fornybar ressurs, og for å sikre en bærekraftig
samfunnsutvikling er vi nødt til å forvalte og ivareta viktige naturog
kulturminneverdier. Hensikten med oppgaven er å undersøke
hvordan lokale ressurser i landskapet kan være et utgangspunkt for
ny verdiskaping og lokalsamfunnsutvikling langs den historiske ruta;
Driftavegen gjennom Viglesdalen.
Natur- og kulturressurser kan være menneskelige spor, et element,
naturen som formgiver eller stedshistorie. Alle kulturmiljøer er en kilde
til erfaring, opplevelse og læring. En utfordring for natur- og kulturarv
er å formidle, og ikke alt kan fortelles gjennom bilde og tekst, derfor er
et landskap en kilde til både historien og tidligere levd liv. Oppgavens
litteraturstudie tar for seg verdiskaping og relasjonelle verdier, og hvilken
måte menneske kobler seg på et fysisk miljø, gjennom opplevelsen av
det. Det er et behov for å kommunisere landskapet på et vis som gjør at
verdiskaping av natur- og kulturmiljø kan nå et bredere publikum. Om
samfunnet ser verdien i å ta vare på landskap, kan også forvaltningen av
det styrkes. Landskap krever både helhetlig og langsiktig planlegging.
Et mål med oppgaven er å fremme Driftavegens særegenheter og
formidle disse på best mulig måte, til flest mulig. Driftavegen er en arena
for synergier mellom lokalsamfunn, og verdiskaping fører med seg
direkte og indirekte virkninger gjennom lokalt arbeid og formidling. Det
er utarbeidet tre strategier i oppgaven, de tre diskursene er: Opplevelse,
tilrettelegging og læring. Hvor alle tre er en form for landskapsformidling
i praksis. Dette skal være et virkemiddel til å bygge en relasjon mellom
mennesket og landskapet, og skape gode besøksopplevelser for
vandreren. Det gir grobunn for et levende lokalsamfunn, og kan åpne
dørene for et regionalt felleskap, på tvers av administrative grenser.It is in modern times that human interventions have reshaped and
changed landscape and natural environment so fundamentally.
Cultural heritage and landscape are a non-renewable resource, and
to ensure sustainable social development, we must manage and look
after important nature- and culture heritage values. The purpose of the
assignment is to investigate how local resources in the landscape can be
an origin for broad value creation and vibrant local communities along
historical walking route through Viglesdalen.
Natural and cultural resources can be human traces, an element,
nature as shaper or local history. All cultural heritage are a source of
experience and learning. A challenge of natural and cultural heritage
is to communicate it, and not all can be told through pictures and
text, therefore landscape is a source of both history and past life. The
assignment’s literature study deals with value creation and relational
values, and the way in which people connect to a physical environment,
through the experience of it. There is a need to communicate the
landscape in a direction that enables value creation of the natural
and cultural environment to reach a wider audience. If society sees
the value in taking care of the landscape, its management can also be
strengthened. Landscapes require both comprehensive and long-term
planning.
One aim of the task is to promote Driftavegen’s peculiarities and
communicate these, to a broad audience. Driftavegen is an arena for
synergies between local communities and value creation, this brings
with it direct and indirect effects through local work and interactions.
Three strategies have been designed in the thesis, and the discourses
are: Experience, facilitation and learning, where all is a form of
landscape mediation in practice. It should be a means of building a
relationship between people and the landscape and create better visitor
experience for walkers. This provides fertile ground for a vibrant local
community, and can open the doors for a regional community, across
administrative borders
High resolution benthic Mg/Ca temperature record of the intermediate water in the Denmark Strait across D-O stadial-interstadial cycles
Dansgaard‐Oeschger (D‐O) climate instabilities that took place during Marine Isotope Stage 3 are connected to changes in ocean circulation patterns and sea ice cover. Here we explore in detail the configuration of the water column of the Denmark Strait during D‐O events 8–5. How the ocean currents and water masses within the Denmark Strait region responded and were connected to the North Atlantic are discussed. We investigate sediment core GS15‐198‐36CC, from the northern side of the Greenland‐Iceland Ridge, at 30‐year temporal resolution. Stable carbon and oxygen isotope reconstructions based on benthic foraminifera, together with a high‐resolution benthic foraminiferal record of Mg/Ca paleothermometry, is presented. The site was bathed by warm intermediate waters during stadials and cool but gradually warming intermediate water during interstadials. We suggest that stadial conditions in the Denmark Strait are characterized by a well‐stratified water column with a warm intermediate water mass that lies beneath a cold fresh body of water where sea ice and brine rejection work in consort to uphold the halocline conditions. Interstadial periods are not a pure replicate of modern times, but rather have two modes of operation, one similar to today, and the other incorporating a brief period of warm intermediate water and increased ventilation.publishedVersio
Early Holocene Establishment of the Barents Sea Arctic Front
A main feature of the Barents Sea oceanography is the Arctic front. The Arctic front marks the transition between the dominating water masses of the Barents Sea: Atlantic Water in the south and Arctic Water in the north. Presently, the Barents Sea Arctic front is directed by the topography of the Bear Island Trough and to some degree the location of the sea ice boundary. During the last glacial maximum, the Svalbard-Barents Sea and Scandinavian Ice Sheets covered the Barents Sea. Hence, no water entered the Barents Sea, neither from the south nor from the north. Following the deglaciation of the Barents Sea, the present-day ocean circulation developed. The evolution of how the present location of the Barents Sea Arctic front established during the early Holocene is documented by foraminiferal relative assemblage data from six core sites along the western Barents Sea margin and opening. The relative abundance of Arctic front indicator Turborotalita quinqueloba, in combination with the cold, polar Neogloboquadrina pachyderma and warm, Atlantic Neogloboquadrina incompta, are used to infer the location of the Barents Sea Arctic front relative to the individual core sites. Until ca. 11 ka BP, the Barents Sea Arctic front followed the western margin of the Barents Sea. All sites along the Barents Sea margin where still dominated by Arctic Water between ca. 11 and 10.2 ka BP, however, the Barents Sea Arctic front turned eastwards into the southwestern Barents Sea. From ca. 10.2 to 8.8 ka BP, the Barents Sea Arctic front moved eastward and was located right above most sites as it followed the Barents Sea margin. The northwestern Barents Sea Arctic front was close to the present location from ca. 8.8 to 7.4 ka BP, however, it was still confined to the southwestern Barents Sea. From ca. 7.4 ka BP, the Barents Sea Arctic front has been located close to the present position, along the margin southwards from Svalbard, turning eastwards along and beyond the northern Bear Island Trough margin
paleoclimatic and paleoceanographic changes in the Nordic Seas
[1] High-resolution records from IMAGES core MD95-2011 in the eastern Norwegian Sea provide evidence for relatively large-and small-scale high-latitude climate variability throughout the Holocene. During the early and mid-Holocene a situation possibly driven by consistent stronger westerlies increased the eastward influence of Arctic intermediate and near-surface waters. For the late Holocene a relaxation of the atmospheric forcing resulted in increased influence of Atlantic water. The main changes in Holocene climate show no obvious connection to changing solar irradiance, and spectral analysis reveals no consistent signature for any periodic behavior of Holocene climate at millennial or centennial timescales. There are, however, indications of consistent multidecadal variability
Co-feeding of live feed and inert diet from first-feeding affects Artemia lipid digestibility and retention in Senegalese sole (Solea senegalensis) larvae
The present study intended to evaluate the effects of early introduction of inert diet in lipid digestibility and metabolism of sole, while larval feed intake, growth and survival were also monitored. Solea senegalensis larvae were reared on a standard live feed regime (ST) and co-feeding regime with inert diet (Art R). Trials using sole larvae fed with Artemia enriched with two different lipid emulsions, containing glycerol tri [1-14C] oleate (TAG) and L-3-phosphatidylcholine-1,2-di-[1-14C] oleoyl (PL), were performed at 9 and 17 days after hatching (DAH) to study lipid utilization. Co-feeding did not affect sole survival rates (ST 59.1 ± 15.9 %; Art R 69.56 ± 9.3 %), but was reflected in significantly smaller final weight at 16 DAH (ST 0.71 ± 0.20; Art R 0.48 ± 0.14 mg). Higher feed intake was observed in sole larvae fed on Artemia enriched with labeled PL at 9 DAH but not at 17 DAH. At 17 DAH, the smaller larvae (Art R treatment) ingested proportionally more Artemia in weight percentage, independently of enrichment. At 9 DAH lipid digestibility was equal among treatments and higher than 90%, while at 17 DAH it was higher in ST treatment (around 73 %) compared to the Art R group (around 66 %). Lipid retention efficiency at 9 DAH was higher in the Art R treatment, reaching values of 50 %, while these values almost duplicated at 17 DAH, ranging up to 80 % in both treatments without significant differences. These results show that co-feeding of live feed and inert diet from first-feeding in Senegalese sole has a toll in terms of growth and lipid digestibility but does not seem to compromise lipid metabolic utilization
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