Heikkinen, R. K. | bioRxiv Science

bioRxiv2026

Energy and heterogeneity shape bird taxonomic and functional gamma-diversity patterns across landscapes in Finland

AimOur aim was to study the effects of energy availability and landscape habitat heterogeneity on bird taxonomic and functional gamma-diversity and propose conservation guidelines based on the results. LocationSouthern and Central Finland Time Period2009-2020 Major Taxa StudiedBirds MethodsWe derived biodiversity variables from bird monitoring line transects to assess the effects of latitude, longitude, and landscape composition, configuration, and heterogeneity at multiple spatial scales: 100, 500, 2,000, and 5,000 m. We tested the effects of these landscape metrics on the total community, bird ecological guilds (species richness and abundance), functional diversity, and overall species specialization index. ResultsWe found clear evidence supporting a positive effect of energy (latitude and soil fertility) and habitat amount on bird abundances. Our results also revealed a northward increasing trend in functional diversity and species specialization. Habitat heterogeneity positively affected both bird abundance and species richness. Heterogeneity of land cover types was shown to promote abundances, while functional measure of landscape heterogeneity was positively connected to species richness. Land use with high anthropogenic activities, such as urban areas and cropland, negatively affected forest specialists and species sensitive to human activities. Main ConclusionsEnergy and habitat heterogeneity and amount are major mutually nonexclusive factors shaping bird communities in Finnish landscapes. Nonetheless, certain land use types favour some guilds while excluding others (for example, urbanized areas or cropland favouring open area species while excluding old-growth forest specialists), showing that biodiversity conservation is a matter of specialized landscapes. Furthermore, different measures of landscape heterogeneity demonstrated positive relationships with the studied bird guilds, highlighting the consistency of the species-heterogeneity relationship.

ecology↗

bioRxiv2026

NordicTraits: imputed species-level functional trait dataset for vascular plants of Denmark, Finland, Iceland, Norway and Sweden

The NordicTraits dataset provides the first comprehensive, imputed, and openly available species-level functional trait resource for all native vascular plants across Denmark, Finland, Iceland, Norway, and Sweden. Functional traits such as plant height, seed mass, and leaf nitrogen content are critical for understanding plant strategies, ecosystem processes including the services they provide to human society, and predicting biodiversity responses to environmental change. The Nordic region has a rich botanical history. However, the absence of a unified trait database has limited trait-based ecological research in this region that is under rapid climate change. To address this gap, we compiled and harmonized trait data from major global databases and regional sources, covering 3,099 vascular plant species. We utilized all together 205 traits in the imputation model with the source data covering, on average, 54% (5-81%) of the species. We employed rigorous data cleaning, taxonomic standardization, and a Random Forest-based imputation framework to fill the missing values, while incorporating phylogenetic information to improve accuracy. The final dataset includes 44 selected key functional traits with no missing values, including both continuous and categorical traits and enabling robust analyses of plant strategies and responses to environmental gradients across the regions diverse temperate, boreal, arctic, and alpine ecosystems. The dataset is particularly valuable for large-scale, multi-species studies, and those focusing on functional community assessments across a wide range of vegetation types. NordicTraits facilitates the paradigm shift from species-based to trait-based ecology, supporting research on biodiversity, conservation, and climate change impact predictions in northern Europe.

ecology↗