Sammanfattning

This thesis delves into the mechanisms driving community assembly, focusing on the impacts of environmental filtering and dispersal limitation on species richness and composition. I explore diversity patterns in vascular plants, soil fungi, and arthropods across two subarctic landscapes and at different spatial scales. As a background, I characterize the similarity in conditions between the two study areas and quantify patterns of alpha, beta and gamma diversity among the target taxa. I then relate these patterns to variation in microclimate, in productivity, and in the dispersal capacity of each taxon. In particular, I examine the influence of microclimatic conditions on species richness and abundance of arthropods and plants, and the similarity in taxon-specific responses to similar drivers. To test for an association between productivity and diversity, I examine alpha and beta diversity patterns of arthropods across productivity gradients at the local, landscape and regional scales, and test for scaledependencies in the patterns observed. Finally, I assess how community dissimilarity varies among taxa across the landscape. Across the two subarctic regions, I found highly similar microclimatic conditions and productivity gradients. In both regions, species richness generally decreases with elevation and increases with soil temperature and moisture. The increase in arthropod richness along productivity gradients is consistent across scales, but plant richness shows weak relationships with arthropod richness. Higher species richness at lower elevations is attributable to species niche shapes, with a majority of “productivitygeneralist” species covering the entire productivity gradient, and a minority of “productivityspecialist” species occurring exclusively at either low- or high-productivity sites – with the latter group being more specious. Higher species richness in high-productive areas did not translate into any greater dissimilarity in community composition. Moreover, highly dispersive species exhibit greater species turnover across the landscape compared to poorly dispersive species. Overall, my findings shed light on how abiotic factors, energy inputs, and dispersal capacity shape communities of plants, fungi and arthropods across subarctic landscapes, highlighting the complex interplay of factors in shaping community assembly.

Nyckelord

Community assembly; Subarctic; environmental filtering; dispersal

Publicerad i

Acta Universitatis Agriculturae Sueciae
2024, nummer: 2024:36
ISBN: 978-91-8046-336-2, eISBN: 978-91-8046-337-9
Utgivare: Swedish University of Agricultural Sciences

SLU författare

• de La Peña Aguilera, Pablo

  • Institutionen för ekologi, Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Ekologi


Publikationens identifierare

DOI: https://doi.org/10.54612/a.457ae5racn

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/128755