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.
2011
Authors
Jan Svtlík Isabella Børja Toril Drabløs Eldhuset Holger Lange Frank Newell Kidder Douglas Lawrence GodboldAbstract
Fungi are the main degraders of organic matter and are associated symbiotically with over 80% of terrestrial plants (Smith and Read 1997). Thus, the extent of the mycelial network is an indicator of the decomposing or symbiotic activity. Although the importance of fungi in soil is undisputable, the determination of the extent of hyphal mats and the hyphal biomass is difficult to assess. Methods for estimating hyphae in soil are mostly based on the gridline intersect method originally developed to determine the root length or recently by measuring of the ergosterol content, fungal sterol found in the cell membranes....
Abstract
This study is a part of a larger project designed to find out the causes of top dieback symptoms in Norway spruce in SE Norway. Because sapwood tracheids constitute a water transport system while parenchyma serves as a reserve tissue (Sellin, 1991), the separation and quantification of the sapwood and heartwood may contribute to understanding of the healthy tree functioning. As the extent of sapwood is related to tree vitality, it reflects the tree growth, health and effect of environmental factors (Sandberg & Sterley, 2009). Therefore, the sapwood cross-sectional area is widely used as a biometric parameter indicating the tree vitality, although its estimation and evaluation is prone to scaling errors....
Authors
Arnold ArnoldussenAbstract
Publiced earlier in English in 2006. In 2011 revised and translated into Chinese.
Authors
Johannes BreidenbachAbstract
The aim in the analysis of sample surveys is frequently to derive estimates of sub-population characteristics. This task is denoted small area estimation (SAE). Often, the sample available for the sub-population is, however, too small to allow a reliable estimate. Frequently, auxiliary variables exist that are correlated with the variable of interest. Several estimators can make use of auxiliary information which may reduce the variance of the estimate.
Abstract
No abstract has been registered
Abstract
Fungal hyphae in soil, although crucial in the C-dynamics, are difficult to quantify. Here we present a simple method for fungal biomass assessment and possibility for up-scaling. Originally we used root nets to quantify fine roots in drought-stressed Picea abies stand as described by Lukac and Godbold (2010).Root nets (7 cm wide, mesh size 1 mm) were inserted vertically to 20 cm depth, twice during the course of one year. When root nets were extracted from the soil, large amounts of hyphae were growing on and through the nets in the control plot, whereas little or no hyphae were growing in nets from the drought-stressed plot.This observation led us to consider root nets as a promising tool to quantify hyphae as well. The inert net material together with its regular geometric pattern is well suited for obtaining fungal biomass estimates and provide a material for further molecular analysis of fungal species. We will describe a proposal how to scan the hyphae, calculate the biomass and upscale to the soil volume unit.
Authors
Bernt-Håvard ØyenAbstract
Bruken av furuskogressursene og trender knyttet til ressursbruken i Vest-Norge er beskrevet. Artikkelen gir råd om skjøtsel av furuskog vestafjells og angir data og noen økonomisk tallsstørrelser knyttet til gårdsskogbruk basert på furuskogressurser i dag.
Abstract
Wood protection in the last century has mainly been based on chemical treatments. Additionally, the type of construction of wooden buildings and the choice of wood species play an important role. Degradation of wood is not only caused by fungi or bacteria but also by insects. Termites have been a potential risk to wooden structures not only in the warmer regions of our continents but also beyond the regions of their natural habitat due to transport of wood. A new treatment, Electro osmotic pulsing technology (PLEOT), has been tested in lab termite tests and fungi tests. The two choice and non-choice termite tests were carried out using different duration of exposure and different initial wood moisture content. The results show growth of mould fungi on untreated wood samples with high initial wood moisture content after 4 weeks of termite testing whereas PLEOT treatment strongly reduced the development of moulds. Termite mortality was high on untreated wood samples with high initial moisture content but not on wood samples with low initial moisture content. This is explained by mould growth on the wetter samples, which termites don\"t tolerate in large amounts. The loss of wood mass due to termite attack could be reduced by using PLEOT. The mortality of termites was higher in test systems with protected wood samples than untreated samples. PLEOT could be used successfully against fungal attack. The treatment reduced on the one hand mould growth in a termite test and on the other hand reduced strongly the attack of brown rot fungi in a lab test.
Abstract
A changing climate will likely influence the selection of tree species in the future, and this may in turn affect the size of the pools and fluxes of carbon. Tree species differ in growth rate, fine-root turnover and quality of litter and tend to produce different types of understory vegetation. In Sweden three tree species (Norway spruce [Picea abies] 43%, Scots pine [Pinus sylvestris] 39% and birch [Betula spp.] 11%) dominate. In the present study we used field experiments in southern Sweden to test if these tree species differed in root distribution and turnover.
Abstract
Biodiversity is assumed to have high value for many people, but the necessary preservation also incurs a cost for the forest owner. Typically, studies of this cost are at the stand level, and hence, not very accurate as the cost may vary even within the stand. In this work, we use a 1m×1m grid, generated from LIDAR data, to estimate the cost for harvesting and forwarding. The method could be utilized to calculate compensation, and to select between key woodland habitats to minimise the cost. In three of four test cases, the main cost was reduced harvested volume, but in one case the key woodland habitat also made the harvesting operations more expensive.