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Context

The effects of landscape structure on biodiversity may change with the spatial and temporal scale at which landscape structure is measured. Identifying the spatial extent and temporal scale at which the biodiversity-landscape relationship is strongest (i.e., the scale of effect) is important to better understand the effect of landscape structure.

Objectives

The spatial and temporal scale of effect is analyzed to identify whether it differs in ecologically distinct species groups. How species richness-landscape relationship changes with spatial and temporal scales is tested.

Methods

Based on 98 survey plots (1 km22) of vascular plants on the Swiss Plateau, we analyzed the relationships between species richness of different species groups and landscape predictors at different spatial extents (1 km22, 4 km22, 16 km22, 36 km22) and time periods (past landscapes—1985, 1997, 2009 and the current landscape 2018).  

Results

The spatial scale of effect was 1 km for most species groups, while the temporal scale of effect differed among species groups. The strength of the species richness-landscape relationship generally decreased with increased spatial extents, while it changed little across temporal scales.

Conclusions

Although our study only considered changes in landscape structure over the last c. 30 years, ecologically distinct species groups revealed differences in the temporal scale of effect including a rapid response of neophytes linked to ongoing biological invasions. However, the variation in the species richness-landscape relationship was greater when changing spatial extent than time. We highlight that studying the relationship between landscape structure and biodiversity should consider not only space but also time, and different responses of ecologically distinct species groups.

Pan, Y., Hersperger, A. M., Kienast, F., Liao, Z., Ge, G., & Nobis, M. P. (2022). Spatial and temporal scales of landscape structure affect the biodiversity-landscape relationship across ecologically distinct species groups. Landscape Ecology. https://doi.org/10.1007/s10980-022-01477-x

Bryophytes provide key ecosystem services at the global scale such as carbon storage and primary production in resource limited habitats, but compared to vascular plants knowledge on how these organisms face recent climate warming is fragmentary. This is particularly critical because bryophytes differ fundamentally from vascular plants in their ecophysiological and biological characteristics, so that community alterations most likely have different dynamics.

In a comparative approach, we analysed thermophilisation of bryophyte and vascular plant communities in 1146 permanent plots distributed along an elevational gradient of nearly 3.000 m in Switzerland (Central Europe) that were visited in 5-years intervals between 2001 and 2021. We estimated thermophilisation from changes in unweighted mean temperature indicator values of species, compared it to expected thermophilisation rates given the shift of isotherms and addressed differences between the two lineages, major land use types (managed grasslands, forests, unmanaged open areas), life strategy types (long- and short-lived species) and in elevation.

Thermophilisation of bryophyte communities was on average 2.1 times higher than of vascular plant communities and at high elevations it approximated the expected rate given the shift of isotherms. Thermophilisation of both, bryophyte and vascular plant communities was not driven by a loss of cryophilic species but by an increase in thermophilic and mesophilic species, indicating an in-filling process. Furthermore, our data show that thermophilisation is higher in managed grasslands than in forests.

We suggest that the higher responsiveness of bryophytes compared to vascular plants depends on their poikilohydry and dispersal capacity and that lower thermophilisation of forests communities is related to the buffering effect of microclimatic conditions in the interior of forests. Our study emphasises the heterogeneity of climate warming effects on plants because response dynamics differ between taxonomic groups as well as between land use types and along elevational gradients.

Kiebacher, T., Meier, M., Kipfer, T., & Roth, T. (2023). Thermophilisation of communities differs between land plant lineages, land use types and elevation. Scientific Reports, 13(1), 11395. https://doi.org/10.1038/s41598-023-38195-6