Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2016
Sammendrag
Nonylphenols (NP) are a group of alkylphenols, formed upon degradation of nonylphenol ethoxylates such as nonylphenol monoethoxylate (NP1EO) or nonylphenol diethoxylate (NP2EO), which have been broadly used as non-ionic surfactants. Both NP and their ethoxylates are often present in the sewage, despite being banned and substituted by less toxic alcohol ethoxylates in many countries. There is a number of degradation studies of nonylphenol in the soil environment, but there is a lack of understanding on how plants and soil organisms such as earthworms can affect the degradation. In our study, we investigated the degradation of 4-nonylphenol (4-NP) in a mineral field soil in the presence of barley (Hordeum vulgare) and earthworms (Aporrectodea caliginosa). Soil was spiked with 4-NP at a concentration of 12.5 mg kg-1 d.w. soil. Results showed that the degradation of 4-NP in soil was rapid during the 28 days after spiking, with remaining concentration of 0.397 mg kg-1 d.w. soil on day 28. Degradation was much slower between days 28 and 120, with a remaining concentration of 0.214 mg kg-1 d.w. soil on day 120. No significant difference in the degradation of 4-NP in the presence of either plants or worms was observed, but sampling after 28 days of exposure revealed transfer of 4-NP to worms (worm tissue concentration = 0.79 μg g-1), which increased with time (1.66 μg g-1 after 120 d). The calculated transfer factor after 28 (TF28) and 120 days (TF120) was 0.07 and 0.13 respectively. No toxicity or accumulation in plants was observed at the concentration tested herein. Concentration of 4-NP in the rhizosphere was not statistically different from that in the bulk soil.
Sammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Forfattere
Ove BergersenSammendrag
This report contains all the monitoring data collected in the course of three years, from 2013 to May 2016. The deposits had high contents of organic material and high water content before monitoring started. Data showed minimum temperatures close to 0-2°C under winter conditions and maximum temperatures at 14°C during the period from May to September in 2013. In 2014 the minimum temperature increased to 6-7°C and the maximum temperature increased to 17-18°C. Data recorded in 2015 showed minimum temperature 7-9°C and maximum temperature at 16-19°C. The average and median values calculated in 2013 were about 11°C, 13°C in 2014 and 14°C in 2015. High soil moisture was found in all layers, and fluctuated with precipitation. This increased more frequently in 2014 and 2015 under periods with high precipitation. This high precipitation frequency the last two years and infiltration of roof water has decreased the redox potential to more anoxic conditions, which is positive for the preservation of the archaeological remains. The previous status report II, written in 2015, informs that the redox sensor was malfunction because of the great curve drop in 2014 for sensors in layer 2 and 3. In 2015, the redox sensors all show more stable conditions of -400, -311 to -11 mV in layers 2, 3 and 4.
Forfattere
Vibeke Vandrup Martens Ove Bergersen Michel Vorenhout Paula Utigard Sandvik Jørgen HollesenSammendrag
This paper presents archaeological observations and results of palaeoecological and geochemical analyses of archaeological deposits from two rural sites in northernmost Norway. These are combined with climate data and the first period of continuous monitoring of soil temperature, moisture and redox potential in sections. This data constitutes the basic research material for evaluations of conservation state and preservation conditions. The data has been collected in collaboration between the partners of a cross disciplinary project. This is an important Norwegian research initiative on monitoring of rural archaeological deposits and the results have consequences for heritage management of a large number of sites from all periods. Palaeoecological analyses and redox measurements have revealed ongoing decay that might not otherwise have been detected. Decay studies indicate that both site types may be at risk with the predicted climate change. Some mitigating acts are suggested.
Sammendrag
Medieval Trondheim is located on the eastern part of Nidarneset, a small peninsula formed by the river plain at the mouth of the River Nid on the southern shore of Trondheimsfjord. The topographic conditions for medieval Trondheim differ from those of the other Norwegian medieval towns (notably Bergen, Oslo, and Tønsberg), and the protected, historic part of Trondheim contains anthropogenic sediments which lie entirely within an unsaturated environment. A large proportion of these sediments contain wood and other types of organic material. The thickness of the anthropogenic sediments varies greatly from more than 4 m to less than 0.5 m, and they overlie well-drained alluvial sands and gravels. The Directorate for Cultural Heritage (Riksantikvaren) and the Norwegian Institute for Cultural Heritage Research (NIKU) have different roles in the management of cultural heritage sites. However, they cooperate in developing sustainable management and a scientific approach to research, as well as finding practical solutions aimed at securing stable preservation conditions for anthropogenic sediments that are vulnerable and sensitive to environmental changes, both chemical and mechanical. In this paper we present results from environmental investigations conducted in 2007 and 2012 at a location in the central part of medieval Trondheim where an in situ preservation project has been established on the site of new construction work. The project is cross-interdisciplinary, combining archaeological retrieval methods with the sampling and analysis of soil chemical parameters and the monitoring of present basic parameters such as temperature, moisture and redox potential. The monitoring has been ongoing since the beginning of 2013 and will continue until 2017.
Sammendrag
No abstract has been registered
Sammendrag
This study examined the P fertilization effects of 11 sewage sludges obtained from sewage treated with Al and/or Fe salts to remove P by a pot experiment with ryegrass (Lolium multiflorum) and a nutrient-deficient sand−peat mixture. Also it investigated whether fertilization effects could be predicted by chemical sludge characteristics and/or by P extraction. The mineral fertilizer equivalent (MFE) value varied significantly but was low for all sludges. MFE was best predicted by a negative correlation with ox-Al and ox-Fe in sludge, or by a positive correlation with P extracted with 2% citric acid. Ox-Al had a greater negative impact on MFE than ox-Fe, indicating that Fe salts are preferable as a coagulant when aiming to increase the plant availability of P in sludge. The results also indicate that sludge liming after chemical wastewater treatment with Al and/or Fe salts increases the P fertilization effect.
Forfattere
Eva BrodSammendrag
No abstract has been registered
Forfattere
Eva BrodSammendrag
No abstract has been registered