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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.

2024

Abstract

Forest grazing by free-roaming livestock is a common practice in many countries. The forestry sector sees the practice as unfortunate owing to several reasons, such as damages inflicted by grazing in young plantations. Concerning Norway spruce forests, a tree species known to develop wood decay with high frequency followed from stem bark damage, there is a strong perception among foresters that the trampling damage caused by livestock on the superficial root system of this tree leads to decay. Because of the very limited scientific documentation available on this topic, we pursued a clarification by investigating three 38- to 56-year-old Norway spruce forests used for silvopasture. Two types of injuries were observed on exposed roots: bark cracks characterized by resin exudation, and injuries involving localized bark peeling and exposure of the underlying wood. These injuries occurred up to 250 cm away from the root collar, with the sector 50–150 cm away from the root collar showing the highest incidence of injuries. In two of the forest stands, wood within the injured root areas was primarily colonized by the wound parasite Corinectria fuckeliana or species of the order Helotiales, fungi that do not cause wood decay. Wood colonization of injured roots by Heterobasidion species, the most frequent wood decay fungi of Norway spruce, was common in the third stand, but only in a few cases it was possible to deduce that the colonization had probably initiated via trampling injuries on roots. In a few cases, an injury was located at stem base at the root collar height along paths used by animals, and in such cases, it was obvious that stem colonization by Heterobasidion species had initiated via the wound. The relatively small amount of data warrants caution when drawing conclusions. Considering the high establishment frequency of decay via stem bark wounds of Norway spruce observed in previous studies, our data would suggest that roots are generally better equipped to defend themselves upon infliction of superficial wounds than stem of this tree species. The likelihood of trampling injuries leading to decay may vary considerably between different stands, this presumably depending on the level of local propagule pressure by pathogenic wood decay fungi and the frequency of damages close to root collar.

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Abstract

This article aims to increase the knowledge of the roles and functions of public health institutes (PHIs) by exploring and comparing the Scandinavian PHIs, their roots, and developments over time. The research questions are the following: What was the history behind these public institutions? How have they changed over time? Have they followed divergent or parallel paths of change? How, if at all, have they been influenced by public sector reforms? Comparing the three Scandinavian countries based on an institutionalist approach, the article seeks to increase the understanding of the role of PHIs in governing public health. The article is based on documents from parliaments and governments from the public health institutes, supplemented by institution narratives and relevant public health and public administration literature. The Scandinavian PHIs have common roots from the early 1900s, have followed different routes, and have different institutional characteristics and different roles as public health institutions. However, after more than 100 years, the Scandinavian PHIs belong to the international PHI organization. They are responsible for knowledge dissemination, surveillance, and preparedness for the handling of epidemics and pandemics. The article argues for more comparative research on institutions related to public health authorities, such as the PHIs.

To document

Abstract

This article aims to increase the knowledge of the roles and functions of public health institutes (PHIs) by exploring and comparing the Scandinavian PHIs, their roots, and developments over time. The research questions are the following: What was the history behind these public institutions? How have they changed over time? Have they followed divergent or parallel paths of change? How, if at all, have they been influenced by public sector reforms? Comparing the three Scandinavian countries based on an institutionalist approach, the article seeks to increase the understanding of the role of PHIs in governing public health. The article is based on documents from parliaments and governments from the public health institutes, supplemented by institution narratives and relevant public health and public administration literature. The Scandinavian PHIs have common roots from the early 1900s, have followed different routes, and have different institutional characteristics and different roles as public health institutions. However, after more than 100 years, the Scandinavian PHIs belong to the international PHI organization. They are responsible for knowledge dissemination, surveillance, and preparedness for the handling of epidemics and pandemics. The article argues for more comparative research on institutions related to public health authorities, such as the PHIs.

Abstract

The fall armyworm, Spodoptera frugiperda, situation in Africa remains a priority threat despite significant efforts made since the first outbreaks in 2016 to control the pest and thereby reduce yield losses. Field surveys in Benin and Mali reported that approximately one-week post-emergence of maize plants, the presence of fall armyworm (egg/neonates) could be observed in the field. Scouting for fall armyworm eggs and neonates is, however, difficult and time consuming. In this study, we therefore hypothesized that the optimum timeframe for the fall armyworm female arriving to lay eggs in sown maize fields could be predicted. We did this by back-calculating from interval censored data of egg and neonates collected in emerging maize seedlings at young leaf developmental stage. Early time of ovipositing fall armyworm after sowing was recorded in field experiments. By using temperature-based models to predict phenological development for maize and fall armyworm, combined with analytical approaches for time-to-event data with censored status, we estimated that about 210 accumulated Degree Days (DD) is needed for early detection of neonate larvae in the field. This work is meant to provide new insights on timely pest detection and to guide for precise timing of control measures.