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.
2010
Forfattere
Anna H. Petersén Anna H. PetersénSammendrag
Det er ikke registrert sammendrag
Sammendrag
The efficiency of different organic waste material as NPK fertilizer and risk for leaching losses related to shower precipitation in the first part of the growing season was testet in a pot experiment on a sandy soil in green house. Six organic fertilizers were evaluated: liquid anaerobic digestate (LAD) of source separated household waste, nitrified liquid anaerobic digestate (NLAD) of same origin as LAD, meat and bone meal (MBM), hydrolysed salmon protein (HSP), reactor composted catering waste (CW) and cattle manure (CM). Unfertilized control, calcium nitrate (CN) and compound fertilizer, Fullgjødsel® 21-4-10 were used as reference fertilizers. Two levels of N-fertilization were applied: 80 kg N ha-1 and 160 kg N ha-1. The amount of fertilizer applied was based on content of mineral N for LAD, NLAD, CN and Fullgjødsel, while Kjeldahl-N content was used for dosage of MBM, HSP, CW and CM. At Zadoks 14 the pots were given a surplus of 28 mm water, as a simulated shower precipitation, and leached water was collected and analyzed for content of N and P. LAD and Fullgjødsel® gave equal yield of barley and uptake of N, P, and K in barley grain, when equal amounts of mineral nitrogen were applied. NLAD gave significantly lower barley yield than the original LAD due to leaching of nitrate-N after simulated surplus of 28 mm precipitation at Zadoks 14. CW also gave yield of barley grain similar to Fullgjødsel®, but significantly less yield of straw. The nutrient content in the different organic fertilizers caused different yield limiting effects. MBM showed K deficiency and had equally small K uptake as CN. Cattle manure had only a small portion of mineral N, and low uptake of N. NLAD had low uptake of P compared to LAD, which also was related to smaller amount of P applied in NLAD. The was significant increased leaching of nitrate N from the treatments receiving 160 kg N ha-1 of CN and NLAD compared to all the other organic fertilizers. It was found significant increased leaching of NH4-N at LAD with 160 kg N ha-1 compared to the other treatments, but the amount of leached NH4-N was very small compared to the nitrate-N leaching for the CN and NLAD treatments. Although the LAD treatment received less P than the CM treatment, the highest P-leaching was found for the LAD treatment. A relatively high proportion of the leached P was PO4-P for the LAD treatment receiving 160 kg N ha-1. CM and CW also had significantly higher P leaching than the other organic fertilizers at 160 kg N ha-1, while most of the treatments had very small P losses and not significantly higher than the unfertilized control. This study showed that liquid anaerobic digestate (LAD) was equally good as NPK fertilizer to barley when equal amounts of mineral N were applied. Liquid anaerobic digestate made of source separated household waste can be recommended as fertilizer to cereals. Nitrification of the ammonium N in the digestate caused significantly increased nitrate leaching, and can not be recommended. The composted catering (CW) and hydrolysed salmon protein (HSP) also showed good fertilizer effect, but these fertilizers had not optimal NPK composition and had lower K content than the crop demand. In these materials are used as fertilizers additional K should be applied in order to obtain normal yields.
Sammendrag
Green algae are known to produce H2 under sulphur deprivation in a process called biophotolysis, where solar energy is used to split water and generate O2 and H2. There is still considerable potential for improvement and very little is known about how this mechanism varies between species. This is part of Bioforsk research activities linked to green algae and H2 production. In order to make a H2 production process from algae economically viable, we face several challenges, including bioreactor design, optimisation of environmental conditions, efficiency improvement by genetic and metabolic engineering. One possibility for improving the economical potential of a hydrogen production process also includes exploitation of the algal biomass which, as a result of stress reactions, may produce metabolites with pharmaceutical value. Joining forces with The Norwegian University of Life Science (UMB) and The Norwegian Forest and Landscape Institute, Bioforsk has established The Norwegian Centre for Bioenergy Research. Bioforsk has also taken a leading role on biogas in the newly established CenBio - a national Centre for Environmental- friendly Energy Research. The modern biogas laboratories are located close to facilities for plant growth studies, making them easy accessible for experimental studies of the entire chain from biomass to fertiliser. Research activities include innovative pre-treatment of substrates for increased biogas yield, effects of substrate mixtures for biogas production and digestate quality, biogas potential and biogas process studies, digestates as fertiliser, and effects on the environment and climate
Forfattere
Kari SkjånesSammendrag
Green microalgae can be used for a number of commercial applications, including health food for human consumption, aquaculture and animal feed, coloring agents, cosmetics and pharmaceuticals. Several products from green algae that are in use today, consist of metabolites which can be extracted from the algal biomass. The most well known examples are the carotenoids astaxanthin and Β-carotene, which are used as coloring agents and for health promoting purposes. Many species of green algae are able to produce valuable components for different uses, examples are antioxidants, several different carotenoids, polyunsaturated fatty acids, vitamins, anticancer and antiviral drugs. In many cases these components are secondary metabolites which are produced when the algae are exposed for stress conditions like for example nutrient deprivation, light intensity, temperature, salinity, pH and other. In other cases the components have been detected in algae grown under optimal conditions, and little is known about how an optimal production of each product could be induced and how their production would react to stress conditions. Some green algae have shown the ability to produce significant amounts of hydrogen gas during sulfur deprivation, a process which is currently extensively studied. At the moment, the majority of research in this field has focused on the model organism Chlamydomonas reinhardtii, but other species of green algae have also showed this ability. Currently there is scarce information available regarding the possibility for producing hydrogen and other valuable components in the same process. This study explores stress conditions which are known to induce production of the different valuable products in comparison with stress reactions leading to hydrogen production. Wild type species of green microalgae with ability to produce hydrogen during anaerobic conditions, and during sulfur deprivation are compared to species with known ability to produce high amounts of certain valuable metabolites. . This information is explored in order to form a basis for selection of wild type species for a future multidiciplinary process, where hydrogen production from solar energy is combined with production of valuable metabolites and other commercial uses of the algal biomass.
Forfattere
Kari SkjånesSammendrag
Det er ikke registrert sammendrag
Sammendrag
The production of hydrogen in green algae is catalyzed by FeFe- hydrogenases, which have high conversion efficiency and high oxygen sensitivity. Most green algae analyzed to date where hydrogenase genes are detected, have been shown to contain two distinct hydrogenases. However, very little is known about which functions the two different enzymes represent. There are also many unknowns within the mechanisms behind hydrogen production as to the roles hydrogenases play under different conditions, and consequently also about the potential for optimization of a hydrogen production process which could be found in this respect. The presented study focuses on the possibility for presence of more than two hydrogenases in a single green alga. A large number of degenerate primers were designed and used to produce 3"-RACE products, which in turn were used to design gene specific primers used for PCR and 5"-RACE reactions. The sequences were aligned with known algal hydrogenases to identify products which had homology to these. Products where homology was identified were then explored further. A high number of clones from each band were sequenced to identify products with similar lengths which would not show up as separate bands on a gel. Sequences found to have homology with algal hydrogenases were translated into putative amino acid sequences and analyzed further to obtain detailed information about the presence of specific amino acids with known functions in the enzyme. This information was used to evaluate the likelihood of these transcripts coding for true hydrogenases, versus hydrogenase-like or narf-like proteins. Conclusion: Evidence showing that Chlamydomonas noctigama is able to transcribe three genes which share a significant number of characteristics with other known algal FeFe-hydrogenases is presented . The three genes have been annotated hydA1, hydA2 and hydA3.
Forfattere
Ketil HaarstadSammendrag
A literature review shows that more than 500 organic and metallic compounds have been reported occurring in wetlands, and also that wetlands are suitable for removing pollutants. There are, however, obvious pitfalls for treatment wetlands, the most important being the maintenance of the hydraulic capacity and controlling the detention time. Treatment wetlands should have an adapted design to target specific compounds. Aquatic plants and soils are suitable for wastewater treatment because they have a high capacity of removing nutrients and other substances through uptake, sorption and microbiological degradation. The heavy metals Cd, Cu, Fe, Ni and Pb were found to exceed limit values in water. Also these studies revealed high values of phenol and SO4. No samples showed concentrations in sediments exceeding limit values, but fish samples showed concentrations of Hg exceeding the limit for fish sold in the EU. The main route of heavy metal uptake in aquatic plants was through the roots in the case of emergent and surface floating plants, whereas in submerged plants roots as well as leaves take part in removing heavy metals and nutrients. Submerged rooted plants have potential from water as well as sediments, where as rootless plants extracted metals rapidly only from water. Caution is due about the use of SSF CWs for the treatment of metal-contaminated industrial wastewater as metals are shifted to another environmental compartment and moreover stable redox conditions are required to ensure long-term efficiency. Mercury is one of the most toxic heavy metals and since wetlands have been shown to be a source of methylmercury. Methyl Hg concentrations are typically approximately 15% of Hgt. In wetland water samples, PAH, bisphenol A, BTEX, hydrocarbons including diesel range organics, glycol, DDT, PCB, cyanide, benzene, chlorophenols and formaldehyde were found to exceed limit values. In sediments only PAH and PCB were found exceeding limit values. In the water phase the pesticides found above limit values were atrazine, simazine, terbutylazine, metolachlor, mecoprop, endosulfan, chlorfenvinphos and diuron. There are few listings of these compounds in the commonly used water quality limit values, except for some well-known endocrine disrupters such as nonylphenol, phtalates etc. The performance of extensive household wastewater treatment systems of removing pharmaceuticals and personal care products (PPCPs) are similar to that obtained in conventional activated sludge wastewater treatment plants
Forfattere
Odd-Arild FinnesSammendrag
Muligheter for ny næring og nye kunnskapsbehov
Forfattere
Anna GrzybekSammendrag
Det er ikke registrert sammendrag
Sammendrag
Styrt beitedrift ved bruk av inngjerding kan være en løsning for å unngå store tap til rovvilt. Det er imidlertid en oppfatning at denne driftsformen kan være en utfordring med hensyn til dyrevelferd, helse og kjøttproduksjon. Bioforsk Nord Tjøtta startet opp et treårig prosjekt sommeren 2008 for å kartlegge beitekapasitet og velferds- og produksjonsparametre i utvalgte sauebesetninger i Nord-Trøndelag som benytter denne driftsformen. I løpet av tre-års perioden er det kartlagt åtte sauebesetninger med tilhørende fem beiteområder i Indre Namdal. To av besetningene ble kartlagt både i 2008 og 2010 for å se på evt. endringer i beitekapasitet og smittebelastning i beiteområdene. Målet med prosjektet er å finne en god balanse mellom arealgrunnlag og dyretall ved hjelp av estimering av beitekapasitet og velferdsvurdering av sauene for å sikre god dyrevelferd og tilfredsstillende kjøttproduksjon på inngjerdete beitearealer. Prosjektet viser at det er mulig å oppnå tilfredsstillende dyrevelferd og produksjonsresultater på inngjerdet beite, men at det kreves en del oppfølging av dyrene i beitesesongen, spesielt med hensyn til parasittproblematikk og beitetilgang.