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.
2015
Abstract
The development of water storage schemes in Sub-Saharan Africa (SSA) is considered a major aid for those regions with unequal water distribution, limited accessibility and anticipated climate change impacts. Great attention is given by many SSA countries to set up different water storage schemes that may improve rural and urban development on a national level. The funding for the water storage schemes is often derived from foreign agencies which conduct feasibility studies for the financing of potential investments. Often however, the feasibility studies rely on a single monetary criterion which may not identify the most appropriate water storage in each case. In addition, limited data availability in many SSA countries increases the difficulty of identifying the most suitable storage option. This paper develops a multicriteria framework for the integrated evaluation of water storage strategies in Sub-Saharan African countries. A set of economic, agronomic and opinion-based criteria are assessed through the PROMETHEE II outranking approach. The introduction of crop modeling complements the limited field data available in agronomic criteria and enhances the scientific rigor of the method. Ethiopia is adopted as a representative case of SSA countries where a diverse set of water storage options is currently under construction, often financed by foreign agencies.
Abstract
The aim of this paper is to evaluate relationships between decomposition rates of Scots pine (Pinus sylvestris) and lodgepole pine (Pinus contorta var. contorta) needle litter in the late stage of decomposition (>30% accumulated mass loss), and the progressively changing concentrations of manganese (Mn), nitrogen (N), and acid unhydrolyzable residue (AUR), as well as mean annual temperature (MAT) and mean annual precipitation (MAP). Using available long-term decomposition studies on pine needle litter in a climate gradient in Sweden, we calculated annual mass loss and related to concentrations of Mn, N, and AUR at the start of each one-year period as well as to MAT and MAP. We investigated these relationships for (i) all data on annual mass loss combined and (ii) annual mass loss for five different decomposition categories as defined by accumulated mass loss. We found highly significant, negative, and dominant relationships between annual mass loss and N (R2 = 0.39) and AUR (R2 = 0.39), a slight but significant positive relationship to Mn (R2 = 0.08) and a significant negative relationship to MAT (R2 = 0.06). The relationships were dynamic, and changed with accumulated mass loss. The rate-dampening effect of N decreased to be a rate-enhancing effect at c. 60–80% accumulated mass loss. A similar trend was found for AUR, becoming rate-enhancing at 70–80% accumulated mass loss. For Scots pine needle litter the effect of MAT on mass loss decreased with increasing accumulated mass loss and changed to a rate-dampening effect at c. 50–70% accumulated mass loss. Mn showed a stimulating effect on mass loss rate in all categories whereas MAP showed no effect in this mainly boreal climatic gradient. The current approach indicates a method for detailed studies of rate-regulating factors for litter decomposition.
Authors
Laura Zoratti Luisa Palmieri Laura Jaakola Hely HäggmanAbstract
Published version. Source at <a href=http://doi.org/10.1093/aobpla/plv117>http://doi.org/10.1093/aobpla/plv117</a>.
Abstract
In Norway domestic sheep are mostly kept on mountain pastures over summer. Previous studies have shown that climate conditions affect the growth of mountain grazing lambs in contrasting ways. We analysed a data-set from the Tjøtta Research farm in northern Norway comprising weights and growth of 8696 lambs over 17 years. The lambs grazed coastal or a mountain pasture, 15 km apart. We found that the lambs grew faster when grazing the mountain pasture. Spring and integrated Normalized Difference Vegetation Index (NDVI) affected only the lambs grazing in the mountains. Winter conditions (North Atlantic Oscillation) and summer temperature had a positive effect on growth in both pastures while spring temperature and spring NDVI were important only in the mountains. The positive effect of spring NDVI suggests that the mountain pasture will produce bigger lambs under future climate warming, while the lambs on the coastal pasture will be less affected.
Abstract
Mold growth on the surface of wooden façades is usuall y dealt with by using surface treatment such as paint with fungicides. However, new developments in architecture ar e m oving towards less use of coating, and more use of untreated wooden clad dings. Mould growth is well understood and described, and several m odels for predicting mould growth on building materials exist. It is commonly k nown that mould growth is directly controlled by the cli mate which the w ood is exposed to. Several authors identify humidity, temperature and time as the main drivers of mould growth. However, most of the cu rrent g rowth models developed are based on lab oratory measurements at stable climatic conditions. Consequently, these models are less suitable for prediction of mould growth on exterior surfaces exposed to rapidly changing weather conditions . T his paper analyses the effect of variations of meteorological data on the mould growth on wooden clad dings. An experimental setup of wood samples was exposed to outdoor conditions and h ourly weather conditions as well as t he mould growth at different intervals were measured. The measurements were supplied with 1- D Heat And Moisture (HAM) simulations to provide a more accurate estimate of the conditions on the surface of th e sa mples. The purpose of the analysis was to evaluate if an existing mould growth model might be applicable also for predicting outdoor mould growth. Several profiles of temperature and moisture were co ntinuously monitored on different locations of an eight - story building made from Cross Laminated Timber (CLT). The results from the an alysis of the samples of wood cladding were used to model the mould growth on different l ocations of the building. Also the drying effect of wind around the building was studied. The study shows that there is large variatio n of potential mould growth on the façade of the building.
Abstract
No abstract has been registered
Authors
Ingunn Øvsthus Tor Arvid Breland Sidsel Fiskaa Hagen Kirsten Brandt Anne-Berit Wold Gunnar Bengtsson Randi SeljåsenAbstract
Organic vegetable production attempts to pursue multiple goals concerning influence on environment, production resources, and human health. In areas with limited availability of animal manure, there is a need for considering various off-farm nutrient resources for such production. Different organic and waste-derived fertilizer materials were used for broccoli production at two latitudes (58° and 67°) in Norway during two years. The fertilizer materials were applied at two rates of total N (80 and 170 kg ha–1) and compared with mineral fertilizer (170 kg ha–1) and no fertilizer. Broccoli yield was strongly influenced by fertilizer materials (algae meal < unfertilized control < sheep manure < extruded shrimp shell < anaerobically digested food waste < mineral fertilizer). Yield, but not glucosinolate content, was linearly correlated with estimated potentially plant-available N. However, extruded shrimp shell and mineral NPK fertilizer gave higher glucosinolate contents than sheep manure and no fertilizer. Sensory attributes were less affected by fertilizer material and plant-available N.
Abstract
Pythium species are fungal-like organisms distributed all over the world. Most Pythium spp. live as saprophytes, but some of them are pathogenic. Here we report on disease incidence in Norway spruce (Picea abies) seedlings caused by Pythium undulatum, and pathogenicity in vitro of Norwegian isolates of P. undulatum and P. anandrum.
Abstract
The objective of this pilot study was to compare resource use in a mountainous summer farming landscape between old and modern dairy cow breeds during a five-day period. The modern breed used a larger part of the landscape than the old breed, most likely due to differences in habitat patterns. The old breed group preferred semi-natural pastures, while the modern breed preferred overgrown semi-natural meadows, intermediate fen, intermediate wooded fen, and grass-rich sub-alpine birch woodland. Both breeds spent most time grazing grasses, but the modern breed showed a higher frequency of grasses and Vaccinium myrtillus in its diet, while the old breed showed a higher frequency of bushes and trees. The pilot study shows some trends supplementing and strengthening earlier results on how modern and traditional cattle breeds are differing in their impact on vegetation based on their use of space and their different diets.
Abstract
No abstract has been registered