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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.

2026

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Abstract

Abstract Atmospheric deposition is a critical driver of biogeochemical cycling in forest ecosystems. Among the pathways of deposition, throughfall (TF) — precipitation that has interacted with the forest canopy — plays a significant role in the input of atmospheric substances and canopy leachates to the forest floor. We investigated the influence of airborne pollen deposited in TF on its chemical composition across 60 Level II plots of the ICP Forests network in eight European countries. Based on 196 TF samples collected during the 2018 early vegetative season, we identified 53 pollen taxa, with Pinus , Picea , Fagus , and Quercus accounting for 91.4% of the total grains. Linear mixed-effects models revealed significant positive links between pollen deposition rates and TF fluxes of several ions, especially potassium (K⁺), which was explained by pollen abundance of all four main tree genera. Additionally, pollen of broadleaved taxa ( Fagus , Quercus ) influenced fluxes of the non-purgeable organic carbon (NPOC), dissolved organic nitrogen (DON), ammonium (NH 4 + ), and phosphate (PO 4 3− ). Conversely, broadleaved pollen showed a weak negative link with nitrate (NO₃⁻) fluxes, even if its interpretation requires a cautious approach, as several non-mutually exclusive pathways could explain it. Fractionation of the DOC pools highlighted a higher potential for microbial origin in broadleaves than in conifers. These findings provide the first continental-scale evidence of a link between pollen and TF water chemistry, concurrently analyzed on each water sample. This study underscores the ecological significance of pollen beyond plant reproduction and the need to consider flowering phenology and pollen release in forest deposition and nutrient assessments.

Abstract

An overview of the European Heathland Network, its history, purpose and role in connecting research, management and policy across Europe. The presentation also highlighted past workshops, current management challenges and priorities for strengthening the network in the future.

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Abstract

Insect pollinators are important drivers of fruit quality and yield in horticultural systems. The global reduction in wild bee populations has increased the demand for managed honeybees, despite honeybees relatively low pollination efficiency. Here, we assessed how bee communities, bee behaviour, and orchard design in Norwegian apple orchards affects apple pollination success, an important determinant of apple quality. We placed pan and vane traps in 18 apple orchards, in six distinct locations, within the two main apple growing regions in Norway. We also tracked individual bees (honeybees, bumblebees, and solitary bees) throughout the apple flowering season, and recorded their flower handling time, number of flower visits, stigma contact, and movement between apple flowers. Finally, we calculated the seed set rate (ovules developed into seeds / total number of ovules) from 908 harvested apples to estimate pollination success. Our key finding is that pollination success was driven by the abundance of wild bees and overall orchard planting design. We found lower pollination success in block design orchards where a single cultivar is planted continuously over a large area, compared to orchards with an integrated design where compatible cultivars are planted within the orchard. We also found that stigma contact decreased as apple flowering progressed, and that solitary bees visited fewer flowers per foraging event but were potentially more thorough foragers. Our results highlight the importance of promoting wild bees in apple orchards while also ensuring there is compatible pollen in the orchards for optimal pollination.