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.
2006
Forfattere
Marianne StenrødSammendrag
Det er ikke registrert sammendrag
Forfattere
Marianne Stenrød Jeanne Perceval Rudi Yi Xu Marit Almvik Randi Bolli Christophe Moni Christian W. Thorstensen Espen Haugland Pierre Benoit Marie-Paule Charnay Ole Martin Eklo Mona le Menn Jens Kværner Tore SveistrupSammendrag
Det er ikke registrert sammendrag
Forfattere
Anne Kristine Søvik Nina SyversenSammendrag
A lysimeter experiment with drained soil columns has been established in order to study the retention efficiency of particles and nutrients from artificial agricultural runoff in soil from a vegetative buffer zone. The effect of vegetation, grass versus trees and alder versus aspen, high and low runoff as well as different seasons has been examined. It was found that the retention of particles, total P and phosphate was significantly higher in the columns with trees compared to the columns with grass. In general this was the case for organic carbon and the nitrogen compounds as well. Columns with aspen and alder had equal retention efficiency for particles, organic matter and total phosphorus. Again this was in general valid for total nitrogen and nitrate as well. The retention efficiency for the measured parameters followed in general the pattern: particles/organic matter > phosphorus > nitrogen. The retention efficiency of the nutrients was generally better during the summer and early autumn compared to late autumn, for particles and organic carbon less difference between the seasons was observed.
Forfattere
Anne Kristine Søvik Nina SyversenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Effects of composting on survival and reproduction of the potato cyst nematode (PCN) Globodera rostochiensis were investigated in 150-liter pilot scale reactors. Small bags containing cysts of PCN were incubated in organic waste and composted for 8, 15 or 29 days. Temperatures in the areas close to the cyst bags were monitored. Survival, measured by hatching, was reduced by 99.9% already after 8 days of composting and at 29 days no hatching was recorded. A few eggs, however, still hatched after being composted for 15 days and exposed to temperatures higher than 60°C for several days. Maximal temperatures and thermal exposure time as such could not explain the hatching pattern of PCN, so other factors are likely to be involved in causing lethality. PCN failed to reproduce after 8 days of composting with temperatures reaching a minimum of 50°C during the period. Hence, eight days of composting where all material have reached a temperature of minimum 50°C during the period, could be regarded as a satisfactory method for sanitation of PCN.
Sammendrag
This document contains a summary of some techniques that can be used for CO2 monitoring considering a field laboratory site with an injection depth in the order of hundreds of meters. We will mainly focus on seismic: 3D and 4D surface seismic, acoustic image, multicomponent (MC) seismic, microseismic monitoring, boreholebased seismic, 4D cross-hole seismic surveying, 4D vertical seismic profiling (VSP); acoustic sonar bathimetry techniques; gravimetric techniques; electrical or electromagnetic techniques: electrical resistance tomography (ERT), ground penetrating radar, borehole radar, magnetotellurics; but geochemical techniques are included, like isotope methods, geochemical tracers, water chemistry. Finally, soil gas techniques and remote sensing methods area also described in this document. Storage of CO2 in geological formations is feasible on industrial scale. At the same time there is a requirement from Environmental and Health Authorities for documentation of subsurface behaviour of CO2. In this document we summarize different approaches for monitoring of subsurface migration, leakage and chemical reactions of CO2. We suggest performing studies at different scales including laboratory and field experiments. The methods we suggest has special emphasize on early detection of small amounts of CO2 migration. Of that reason the main focus of this report is on indirect geophysical monitoring (viz seismic, electrical and electromagnetic methods). To document subsurface reactions we also include geochemical methods. We suggest including ecological monitoring as an integrated part of the field experiments. Ecological monitoring will provide detection (or confirmation) of moderate CO2 leakage to the soil surface, and at the same time quantify effects on the vegetation of potentially leakages from geologically-stored CO2. In order to add value to the monitoring program, we recommend initiating simulation of monitoring experiments as early as possible in the project. Simulation of monitoring experiments should then be coupled to inverse flow simulations in order to optimize the monitoring program. Finally, monitoring of two specific field sites is suggested: The Brumunddal sandstone, and the Svelvik ridge in the outlet of the Drammensfjord. The preliminary budget for monitoring a field experiment on each side is 27.3 and 30.2 million NOK respectively. Recommendations for further work include: " Geological characterization of storage site and surrounding area. " Production of geological and numerical flow models of storage site and surrounding area. " Simulation of CO2 injection into the geological formation to identify potential migration and thus leakage points. This includes physical and chemical changes of the reservoir rock and surrounding strata. " Risk assessment to identify features, events and processes that might lead to the migration of CO2 and potential leakage. " Establish monitoring based on step 3 and 4 above. This includes monitoring of subsurface and surface area surrounding the storage site. " History matching of observations and simulation results (and if necessary modification of monitoring acquisitions).
Forfattere
Harald Johansen Olaf Huseby Per Aagaard Eivind Aker Nils-Otto Kitterød al etSammendrag
Det er ikke registrert sammendrag
Sammendrag
The effect of concentrate supplementation on nitrogen (N) intake and excretion in grazing lactating dairy cows was determined in three herds in Norway. Grazing trials were conducted with each herd in June and August for two consecutive years. The average supplementation was 1.8 (S.D. 2.1) kg DM/day, and the concentrate was based on grain with a N content ranging from 18.7 to 24 g/kg DM. Herbage DM and N intake were reduced with increasing supplementation, but total DM and N intake increased. Milk yield and protein content increased by 1.1 kg milk and 0.28 g protein per kg milk for each kg extra concentrate. Milk N excretion increased with increasing supplementation (6.5 g N/kg DM), and N utilisation improved by 11.7 g N per kg N intake per kg extra concentrate. Excretion of urine N and its share of total excreta N decreased by 4.0 and 9.2 g/kg concentrate, respectively. The reducing effect on urine N excretion of supplementation was, however, numerically low compared with other studies, most likely due to a high crude protein content of the concentrate used. (c) 2006 Elsevier B.V. All rights reserved.
Sammendrag
Use of high energy feed supplementation can improve the protein retention by the cattle, and it has been suggested as a way to increase the nitrogen (N) effi-ciency of dairy production. However, in praxis feed supplementation is also used to increase the intensity of animal production above the level that can be supported by the farm's local plant production. A collection of published surveys showed that dairy farms that buy feed are considerably lees N efficient than farms that supply the entire animal ration from their own plant production. The total N emission to the environment per litre milk doubled when 30% of the total feed ration was produced outside the dairy farm. This was so for organic as well as conventional farms. Similar results can be expected for phosphorous and other nutrients. In order to ensure a sustainable and environmentally friendly organic production, imports of feed produced far away from the dairy farm should be strictly limited. We suggest a ceiling of 5 - 10% of total feed ration.
Sammendrag
Use of high energy feed supplementation can improve the protein retention by the cattle, and it has been suggested as a way to increase the nitrogen (N) effi-ciency of dairy production. However, in praxis feed supplementation is also used to increase the intensity of animal production above the level that can be supported by the farm's local plant production. A collection of published surveys showed that dairy farms that buy feed are considerably lees N efficient than farms that supply the entire animal ration from their own plant production. The total N emission to the environment per litre milk doubled when 30% of the total feed ration was produced outside the dairy farm. This was so for organic as well as conventional farms. Similar results can be expected for phosphorous and other nutrients. In order to ensure a sustainable and environmentally friendly organic production, imports of feed produced far away from the dairy farm should be strictly limited. We suggest a ceiling of 5 - 10% of total feed ration.