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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.

2010

Abstract

Soil, composed of minerals, organic material, air and water, performs a number of key environmental, social and economic services that are vital to life. Supplying water and nutrients to plants while at the same time protecting water supplies by storing, bufferingand transforming pollutants. Soil is also an incredible habitat that provides raw materials, preserves our history and limits floods. Without soil, the planet as we know it would not function. However, the importance of soil and the multitude of environmental services that depend on soil properties are not widely understood by society at large. Soil scientists are becoming increasingly aware of the necessity to produce material to raise awareness and educate the general public, policy makers and other scientists of the importance and global significance of soil. This is particularly true of soils in northern latitudes where the impacts of global climate change would be dramatic on both a local and global perspective.

To document

Abstract

In Scandinavia, high losses of soil and particulate-bound phosphorus (PP) have been shown to occur from tine-cultivated and mouldboard-ploughed soils in clay soil areas, especially in relatively warm, wet winters. Omitting primary tillage (not ploughing)in autumn and continuous crop cover are generally used to control soil erosion. In Norway, ploughing and shallow cultivation of sloping fields in spring instead of ploughing in autumn has been shown to reduce particle transport by up to 89% on soils with high erodibility. Particle erosion from clay soils can be reduced by 79% by direct drilling in spring compared with autumn ploughing. Hence, field experiments in Scandinavia on ploughless tillage of clay loams and clay soils compared with conventional ploughing in autumn usually show reductions in total P losses of 10-80%, via both surface runoff and subsurface runoff (lateral movements to drains). However, the effects of not ploughing during autumn on losses of dissolved reactive P (DRP) are frequently negative, since the proportion of DRP losses without ploughing compared conventional ploughing has increased up to fourfold in field experiment. In a comprehensive Norwegian field experiment at a site with high erosion risk the proportion of DRP compared to total P has increased twice in water after direct drilling compared to ploughing before winter wheat. Therefore erosion control measures should be further evaluated for fields with a low erosion risk since reduction in PP losses may be low and DRP losses still high. Ploughless tillage systems have potential side-effects, including an increased need for pesticides to control weeds (e.g. Elytrigia repens (L.) Desv. ex Nevski) and plant diseases (e.g. Fusarium spp.) harboured by crop residues on the soil surface. Overall, soil tillage systems should be appraised for their positive and negative environmental effects before they are widely used for all conditions of soil, management practices, climate and landscape.

Abstract

This report gives an overview of some characteristics of the Vansjø-Hobøl (Morsa) catchment in Southern Norway. The catchment is one of the most studied catchments in Norway in terms of water quality, partly because it has been a pilot project for the implementation of the EU Water Framework Directive (WFD), partly because eutrophication and harmful algal blooms have been a problem in the latter years. Information from the catchment has until now been scattered in several different papers and reports, and most of these have been written in Norwegian.

Abstract

The objective of the research work has been to investigate whether the quality of dried and planed sawn timber can be improved by sorting logs and planks before the drying process. The research material was selected by randomly choosing 30 butt logs and 30 middle logs in a given diameter class at a sawmill. The logs were sawn in a 4 x log pattern, and one inner plank (near pith) and one outer plank (near bark) were chosen from each log. Various properties were measured on the logs and on the sawn timber before and after drying. The material was then planed, and the quality of the panel boards was registered. Based on the results, different models for sorting the timber before drying to optimise the drying process are proposed. One of them is to separate outer and inner planks. An evident improvement is then expected, both due to possibilities for adjusting the drying process to the moisture content before and after drying, and the possibilities for optimising the drying process in accordance with the requirements of the various wood products. In addition to a separation of inner and outer planks, it is also of interest to separate planks from different types of logs (e.g. butt logs and middle logs) to be able to further optimise the drying process according to the wood properties. The project results also show that the best wood quality for production of panel boards is found in the inner planks from middle logs, mainly due to the knot pattern in the stems.