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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.

2023

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Abstract

Black soil is a major agricultural soil in China. Based on published research papers and related research, this chapter reviews the composition, diversity, and ecological functions of farmland soil microbial communities in black soil areas of China. The aim is to summarize the main groups of soil microorganisms in black soil farmland, the ecological processes they participate in, their responses to environmental factors, and the main environmental indicators, and then put forward the importance of isolation and cultivation of indigenous functional microbial strains, so as to provide a basis for the protection and sustainable use of black soil resources.

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Abstract

Why should the producers be subsidized? What are the contributions and channels of subsidies in total factor productivity (TFP) and profitability changes? We address these in a novel way by decomposing TFP and profitability changes into technical change, scale economies, subsidies, input and output misallocations, and inefficiency. A battery of models is deployed to answer these questions, instead of using a single model as done in past studies. First, we use both parametric and nonparametric approaches and estimate them treating subsidies as either exogenous or endogenous. Second, we reexamine both approaches with and without inefficiency. Third, we check the robustness of results across different models using a panel of Norwegian farms. The empirical results show an overall increase of 2.3% per annum in profitability in which the subsidy, scale, and inefficiency components contributed, on average, positively. It is important to note that the magnitude of these components varies across models.

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Abstract

The durability against decay organisms is an essential material property for wood in outdoor use. A jack of all trades method for above-ground wood durability testing has been sought for decades, but until now no method has found its way into European standardization. The method of choice shall be applicable for untreated and treated wood—ideally also for wood composites. It shall further be reproducible, objective, fast, easy, and inexpensive. Finally, it shall provide high predictive power. This study was aimed at a review of results and practical experience with the Bundle test method which could serve as a standard procedure for above-ground field tests of wood-based materials. The method allows for water-trapping, creates a moderate moisture-induced decay risk typical for UC 3 situations, and was found applicable for a wide range of wood materials. The method allows for rapid infestation and failure of non-durable reference species within five years in Central Europe. Based on results from Bundle tests with different modifications and performed at different locations, a guideline has been developed. The method is recommended as a suitable tool for determining the durability of various wood-based materials including modified and preservative-treated wood and can provide data for durability classification.

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Abstract

Butt rot is a main defect in Norway spruce (Picea abies (L.) Karst.) trees and causes large economic losses for forest owners. However, little empirical research has been done on the effects of butt rot on harvested roundwood and the magnitude of the resulting economic losses. The main objective of this study was to characterize the direct economic losses caused by butt rot in Norway spruce trees for Norwegian forest owners. We used data obtained from seven cut-to-length harvesters, comprising ∼400,000 trees (∼140,000 m3) with corresponding stem profiles and wood grade information. We quantified the economic losses due to butt rot using bucking simulations, for which in a first case, defects caused by butt rot were included, and in a second case, all trees were assumed to be free of butt rot. 16% of trees were affected by butt rot, whereby butt rot tended to occur in larger trees. When butt rot was present in a tree, the saw log volume was reduced by 48%. Proportions of roundwood volume affected by butt rot varied considerably across harvested stands. Our results suggest that butt rot causes economic losses upwards of 7% of wood revenues, corresponding to € 18.5 million annually in Norway.