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
Abstract
Minable rock phosphate is a finite resource. Replacing mineral phosphorus (P) fertilizer with P-rich secondary resources is one way to manage P more efficiently, but the importance of physicochemical and microbial soil processes induced by secondary resources for plant P uptake is still poorly understood. Using radioactive-labeling techniques, the fertilization effects of dairy manure, fish sludge, meat bone meal, and wood ash were studied as P uptake by barley after 44 days and compared with those of water-soluble mineral P (MinP) and an unfertilized control (NoP) in a pot experiment with an agricultural soil containing little available P at two soil pH levels, approximately pH 5.3 (unlimed soil) and pH 6.2 (limed soil). In a parallel incubation experiment, the effects of the secondary resources on physicochemical and microbial soil processes were studied. The results showed that the relative agronomic efficiency compared with MinP decreased in the order: manure ≥fish sludge ≥wood ash ≥meat bone meal. The solubility of inorganic P in secondary resources was the main driver for P uptake by barley (Hordeum vulgare). The effects of secondary resources on physicochemical and microbial soil processes were of little overall importance. Application of organic carbon with manure resulted in microbial P immobilization and decreased uptake by barley of P derived from the soil. On both soils, P uptake by barley was best explained by a positive linear relationship with the H2O + NaHCO3-soluble inorganic P fraction in fertilizers or by a linear negative relationship with the HCl-soluble inorganic P fraction in fertilizers.
Abstract
Mineable rock phosphate is a limited resource. Replacing mineral phosphorus (P) fertiliser with P-rich secondary resources is one way to manage P more efficiently. The Norwegian potential to replace mineral P fertiliser with total P in secondary resources was analysed here using substance flow analysis. The results obtained were integrated with data on P plant-availability in secondary resources and showed that, theoretically, plant-available P in manure alone could fulfil the Norwegian demand for P fertiliser. However, P in manure is inefficiently utilised due to the geographical segregation of animal husbandry and arable farming, which contributes to considerable P over-application to agricultural soil. In Norway, agriculture and aquaculture drive P consumption and losses at similar levels, and the amount of P in fish excrement and feed losses from off-shore aquaculture pens (fish sludge) is of the same order of magnitude as P in manure. Fish sludge is currently not collected or utilised, but lost to coastal marine waters. All other secondary resources represent relatively small amounts of P, but may still be important regionally. Political incentives are thus needed in current regulations to efficiently close P cycles. To achieve P recycling in practice, it is essential to know the relative agronomic efficiency (RAE) of secondary P products compared with mineral fertiliser. Nine secondary P products were analysed here: Two biomass ashes, meat bone meal, fish sludge, catering waste, two food waste-based digestate products, dairy manure and chicken manure. The RAE of these secondary products studied in a bioassay with ryegrass (Lolium multiflorum) varied widely, partly depending on soil pH. Fertilisation effects were mainly attributable to the solubility of the inorganic P species contained in the secondary products. Combining sequential chemical fractionation and non-destructive speciation methods revealed that P was mainly present as calcium phosphates of differing solubility. Further analysis showed that microbial and physicochemical soil processes induced by the secondary P products studied were of little overall importance for total P uptake in barley (Hordeum vulgare). Based on the results obtained, two chemical extraction methods for predicting the RAE of secondary products with unknown fertilisation effects are suggested: At soil pH <6.5, RAE should be predicted by the fraction of inorganic P in the secondary product (% of total P) that is extractable in H2O. At soil pH >6.5, RAE should be predicted by the fraction of inorganic P (% of total P) that is extractable in 0.5 M NaHCO3 (Olsen P).
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Authors
Eva BrodAbstract
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Eva BrodAbstract
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Ove BergersenAbstract
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.
Abstract
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.
Abstract
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.
Abstract
No abstract has been registered