Publications by authors named "Anne Sverdrup-Thygeson"

Forests contribute to numerous ecosystem functions and services and contain a large proportion of terrestrial biodiversity, but they are being negatively impaced by anthropogenic activities. Forests that have never been clear-cut and have old growth characteristics, termed "near-natural," often harbor different and richer species assemblages than managed forests. Alternative management strategies may be able to balance the needs of biodiversity with the demands of forestry, but evaluation efforts are limited by the challenges of measuring biodiversity.

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Article Synopsis
  • Functional trait approaches in ecology struggle due to unclear hypotheses about how traits interact with environmental factors, which complicates understanding of ecological mechanisms.
  • Community-weighted mean trait values (CWMs) can skew insights since they mainly represent dominant species, while hierarchical joint species distribution models (JSDMs) provide a broader view of trait-niche relationships.
  • A study of saproxylic beetles in Finland showed that trait-niche relationships varied depending on the metric used, with CWMs indicating more support for these relationships than JSDMs, emphasizing the need for careful metric selection in ecological research.
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The species-energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e.

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Climate, topography and the 3D structure of forests are major drivers affecting local species communities. However, little is known about how the specific functional traits of saproxylic (wood-living) beetles, involved in the recycling of wood, might be affected by those environmental characteristics.Here, we combine ecological and morphological traits available for saproxylic beetles and airborne laser scanning (ALS) data in Bayesian trait-based joint species distribution models to study how traits drive the distributions of more than 230 species in temperate forests of Europe.

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The role of insects in the transfer of radionuclides has received little attention, despite their key role in nutrient cycling within ecosystems. In this study, we investigated the trophic food chain transfer of radiocaesium (Cs) from reindeer meat to the blowfly Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae) and further from blowfly pupae to the parasitoid wasp Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae). Radiocaesium was transferred to blowfly larvae during their feeding stage, with the highest whole-organism to food source concentration ratios (CR) being found in actively feeding third instar blowfly larvae, with CR in the range of 0.

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Recent progress in the taxonomy of flat bark beetles (Cucujidae), specifically, in the genus Cucujus, has revealed great diversity in subtropical Asia, but the seemingly well-known temperate and boreal taxa need further attention because of their conservation status. Here, we used an integrative approach using morphology, DNA, and species distribution modelling to disentangle phylogenetic relations, verify the number of species, and understand the historical biogeography of Palearctic and Nearctic Cucujus beetles, particularly the C. haematodes species group.

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During decomposition of organic matter, microbial communities may follow different successional trajectories depending on the initial environment and colonizers. The timing and order of the species arrival (assembly history) can lead to divergent communities through priority effects. We explored how assembly history and resource quality affected fungal communities and decay rate of decomposing wood, 1.

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Biological communities within living organisms are structured by their host's traits. How host traits affect biodiversity and community composition is poorly explored for some associations, such as arthropods within fungal fruit bodies. Using DNA metabarcoding, we characterized the arthropod communities in living fruit bodies of 11 wood-decay fungi from boreal forests and investigated how they were affected by different fungal traits.

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The amount of carbon stored in deadwood is equivalent to about 8 per cent of the global forest carbon stocks. The decomposition of deadwood is largely governed by climate with decomposer groups-such as microorganisms and insects-contributing to variations in the decomposition rates. At the global scale, the contribution of insects to the decomposition of deadwood and carbon release remains poorly understood.

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The extinction of species is a non-random process, and understanding why some species are more likely to go extinct than others is critical for conservation efforts. Functional trait-based approaches offer a promising tool to achieve this goal. In forests, deadwood-dependent (saproxylic) beetles comprise a major part of threatened species, but analyses of their extinction risk have been hindered by the availability of suitable morphological traits.

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Veteran hollow trees are keystone structures in ecosystems and provide important habitat for a diverse set of organisms, many of which are involved in the process of decomposition. Since veteran trees are 'islands' of high biodiversity, they provide a unique system in which to study the relationship between biodiversity and decomposition of wood. We tested this relationship with a balanced experiential design, where we quantified the taxonomic and functional diversity of beetles directly involved in the process of decomposing wood, and measured the decomposition of experimentally added bundles of small diameter wood around 20 veteran trees and 20 nearby young trees in southern Norway.

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Globally, many insect populations are declining, prompting calls for action. Yet these findings have also prompted discussion about sampling methods and interpretation of long-term datasets. As insect monitoring and research efforts increase, it is critical to quantify the effectiveness of sampling methods.

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Predation of invertebrate pest by natural enemies is a critical contribution of nature to people, because invertebrate pests cause a vast amount of economic damage and pesticides use has many long-term costs. Veteran trees are keystone structures and hotspots for biodiversity, and are a potential source of natural enemies. To explore this, we used a balanced experimental design where we measured predatory beetle diversity and attack marks on three colors of artificial caterpillars placed around 20 veteran oaks and 20 nearby young oaks, in Southern Norway.

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Successional processes can be observed for many organisms and resources, but most studies of succession have focused on plants. A general framework has been proposed, advocating that successional patterns in species turnover are predominantly driven by competition, dispersal or abiotic limitation, and that the patterning of species accumulation over time gives clues to which process is most influential in a given system. We applied this framework to succession in communities of wood-living beetles, utilizing ephemeral resources in the form of 60 experimentally created dead aspen high stumps.

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Understanding the effects of landscape fragmentation on global bumblebee declines requires going beyond estimates of abundance and richness and evaluating changes in community composition and trophic and competitive interactions. We studied the effects of forest fragmentation in a Scandinavian landscape that combines temperate forests and croplands. For that, we evaluated how forest fragmentation features (patch size, isolation and shape complexity, percentage of forest in the surroundings) as well as local flowering communities influenced bumblebee abundance, richness and community composition in 24 forest patches along a fragmentation gradient.

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Veteran hollow oaks ( spp.) are keystone structures hosting high insect diversity but are declining in numbers due to intensification of land use and the abandonment of traditional management. The loss of this vital habitat is resulting in a reduction of biodiversity, and this likely has consequences for ecosystem functioning, especially if functional diversity is reduced.

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There is growing evidence that biodiversity is important for ecosystem functions. Thus, identification of habitat requirements essential for current species richness and abundance to persist is crucial. Hollow oaks ( spp.

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Ecological networks are composed of interacting communities that influence ecosystem structure and function. Fungi are the driving force for ecosystem processes such as decomposition and carbon sequestration in terrestrial habitats, and are strongly influenced by interactions with invertebrates. Yet, interactions in detritivore communities have rarely been considered from a network perspective.

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Over the past centuries, humans have transformed large parts of the biosphere, and there is a growing need to understand and predict the distribution of biodiversity hotspots influenced by the presence of humans. Our basic hypothesis is that human influence in the Anthropocene is ubiquitous, and we predict that biodiversity hot spot modeling can be improved by addressing three challenges raised by the increasing ecological influence of humans: (i) anthropogenically modified responses to individual ecological factors, (ii) fundamentally different processes and predictors in landscape types shaped by different land use histories and (iii) a multitude and complexity of natural and anthropogenic processes that may require many predictors and even multiple models in different landscape types. We modeled the occurrence of veteran oaks in Norway, and found, in accordance with our basic hypothesis and predictions, that humans influence the distribution of veteran oaks throughout its range, but in different ways in forests and open landscapes.

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Body size correlates with a large number of species traits, and these relationships have frequently been used to explain patterns in populations, communities, and ecosystems. However, diverging patterns occur, and there is a need for more data on different taxa at different scales. Using a large dataset of 155,418 individual beetles from 588 species collected over 13 years of sampling in Norway, we have explored whether body size predicts abundance, seasonality, and phenology in insects.

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Ancient trees are considered one of the most important habitats for biodiversity in Europe and North America. They support exceptional numbers of specialized species, including a range of rare and endangered wood-living insects. In this study, we use a dataset of 105 sites spanning a climatic gradient along the oak range of Norway and Sweden to investigate the importance of temperature and precipitation on beetle species richness in ancient, hollow oak trees.

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One of the largest threats to biodiversity is land use change and habitat loss. Hollow oaks (Quercus spp. L.

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Community assembly is an integral process in all ecosystems, producing patterns of species distributions, biodiversity, and ecosystem functioning. Environmental filters and colonization history govern the assembly process, but their relative importance varies depending on the study system. Dead wood decomposition is a slow process, allowing decomposer communities to develop within a slowly changing substrate for decades.

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Industrial forestry typically leads to a simplified forest structure and altered species composition. Retention of trees at harvest was introduced about 25 years ago to mitigate negative impacts on biodiversity, mainly from clearcutting, and is now widely practiced in boreal and temperate regions. Despite numerous studies on response of flora and fauna to retention, no comprehensive review has summarized its effects on biodiversity in comparison to clearcuts as well as un-harvested forests.

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In order to safeguard biodiversity in forest we need to know how forest policy instruments work. Here we use a nationwide network of 9400 plots in productive forest to analyze to what extent large-scale policy instruments, individually and together, target forest of high conservation value in Norway. We studied both instruments working through direct regulation; Strict Protection and Landscape Protection, and instruments working through management planning and voluntary schemes of forest certification; Wilderness Area and Mountain Forest.

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