Search

Aim Biodiversity hotspots are widely used as conservation priorities to preserve the tree of life. However, many conservation practices identify biodiversity hotspots without considering phylogenetic diversity (PD), which reflects total evolutionary history and feature diversity of a region. Moreover, conservation planning rarely distinguishes between neo- and palaeo-biodiversity hotspots despite their differences. Here, we (a) estimated large-scale patterns in PD of woody plants, (b) identified neo- and palaeo-biodiversity hotspots and (c) demonstrated their implication in conservation planning, with special focus on Hengduan Mountains and southern China. Location China. Methods Distributions of 11,405 woody species from the Atlas of Woody Plants in China were updated and were transformed into a grid of 50 x 50 km(2). By integrating distribution maps with a genus-level phylogeny of angiosperms, we estimated Faith's PD of each grid cell and evaluated the contribution of species relatedness to PD at given levels of species diversity (i.e. standardized PD, sPD) using regressions and three null models. Then, we identified areas with significantly lower or higher sPD than expected as neo- and palaeo-hotspots and estimated the coverage of protected areas in these regions. Results Species diversity and PD decreased towards the north. Southern China had high species diversity, PD and sPD, while Hengduan Mountains had high species diversity and PD but low sPD. The coverage of protected areas in southern China was less than half of that in Hengduan Mountains and entire China. Main conclusions Our results identified Hengduan Mountains as a neo-hotspot and southern China as a palaeo-hotspot, highlighting their importance for biodiversity conservation. Compared to Hengduan Mountains, southern China has low coverage of protected areas, which calls for more conservation attention. Our study demonstrates a way of incorporating the phylogenetic component in the identification of neo- and palaeo-hotspots, and hence of achieving a more complete perception of biodiversity patterns for conserving the tree of life., Diversity and Distributions, 27 (1), ISSN:1366-9516, ISSN:1472-4642

[Aim] Alpine habitats support unique biodiversity confined to high-elevation areas in the current interglacial. Plant diversity in these habitats may respond to area, environment, connectivity and isolation, yet these factors have been rarely evaluated in concert. Here we investigate major determinants of regional species pools in alpine grasslands, and the responses of their constituent species groups., [Location] European mountains below 50° N., [Time period] Between 1928 and 2019., [Major taxa studied] Vascular plants., [Methods] We compiled species pools from alpine grasslands in 23 regions, including 794 alpine species and 2,094 non-alpines. We used species–area relationships to test the influence of the extent of alpine areas on regional richness, and mixed-effects models to compare the effects of 12 spatial and environmental predictors. Variation in species composition was addressed by generalized dissimilarity models and by a coefficient of dispersal direction to assess historical links among regions., [Results] Pool sizes were partially explained by current alpine areas, but the other predictors largely contributed to regional differences. The number of alpine species was influenced by area, calcareous bedrock, topographic heterogeneity and regional isolation, while non-alpines responded better to connectivity and climate. Regional dissimilarity of alpine species was explained by isolation and precipitation, but non-alpines only responded to isolation. Past dispersal routes were correlated with latitude, with alpine species showing stronger connections among regions., [Main conclusions] Besides area effects, edaphic, topographic and spatio-temporal determinants are important to understand the organization of regional species pools in alpine habitats. The number of alpine species is especially linked to refugia and isolation, but their composition is explained by past dispersal and post-glacial environmental filtering, while non-alpines are generally influenced by regional floras. New research on the dynamics of alpine biodiversity should contextualize the determinants of regional species pools and the responses of species with different ecological profiles., The authors thank Daniela Gaspar for support in GIS analyses. B.J.-A. thanks the Marie Curie Clarín-COFUND program of the Principality of Asturias-EU (ACB17-26), the regional grant IDI/2018/000151, and the Spanish Research Agency grant AEI/ 10.13039/501100011033. J.V.R.-D. was supported by the ACA17-02FP7 Marie Curie COFUND-Clarín grant. G.P.M. was funded by US National Science Foundation award 1853665. C.M. was funded by grant no. 19-28491 of the Czech Science Foundation.

Aim We use cluster analysis to delimit climatically and functionally distinct mammalian faunal clusters. These entities form regional species pools and are relevant to community assembly processes. Similar clusters can be differentiated in the fossil record, offering the potential for use as palaeoenvironmental proxies. Location North America within W178 degrees, W14 degrees, N83 degrees, N7 degrees and Europe within W32 degrees, E35 degrees, N80 degrees, N35 degrees. Major taxa studied 575 and 124 land mammal species from North America and Europe. Methods K-means clustering was used to subdivide North America and Europe into distinct faunas ranging in number from 3 (largest scale) to 21 (smallest scale). Each set of faunas was tested for significant differences in climate (mean annual precipitation, mean annual temperature) and functional traits (body mass, locomotion and diet). Results In North America, climatic differentiation exists at the scale where mammals are divided into 11 or fewer distinct faunas and, in Europe, at the scale where there are five or fewer faunas. Functional trait differentiation in body mass occurs at a larger spatial scale in North America (8 distinct faunas), but locomotor differentiation is present at all spatial scales, and dietary differentiation is not present at any scale. No significant differentiation in any functional trait at any scale was found in Europe. Main conclusions Faunal clusters can be constructed at any spatial scale, but clusters are climatically and functionally meaningful only at larger scales. Climatic (and environmental) differences and their associated functional trait specialisations are likely to be barriers to large-scale mixing. We argue, therefore, that functionally and climatically distinct faunal clusters are the entities that form regional species pools for community assembly processes. In North America, there are eight such mammal pools, but only one in Europe. Since the functional traits in our study are observable in the fossil record, functional trait analysis can potentially be used to diagnose climatically distinct regions in the past.

The role of dispersal in the assembly of microbial communities remains contentious. This study tested the importance of dispersal limitation for the structuring of local soil bacterial communities using an experimental approach of propagule addition. Microbes extracted from soil pooled from samples collected at 20 localities across ~ 400 km in a temperate steppe were added to microcosms of local soils at three sites; the microcosms were then incubated in situ for 3 months. We then assessed the composition and diversity of bacterial taxa in the soils using 16S rRNA gene amplicon sequencing. The addition of the regional microbial pool did not cause significant changes in the overall composition or diversity of the total bacterial community, although a very small number of individual taxa may have been affected by the addition treatment. Our results suggest a negligible role of dispersal limitation in structuring soil bacterial communities in our study area.

Explanations of biogeographic diversity patterns have emphasized the role of large-scale processes that determine species pools, whereas explanations of local patterns have not. We address the hypothesis that local diversity patterns are also primarily dependent on the size of the available species pools, which are expected to be large when the particular habitat type has been evolutionary more abundant, or in unproductive habitats due to shorter generation time and hence higher diversification rates