Beyond taxonomic diversity: Revealing spatial mismatches in phylogenetic and functional diversity facets in Mediterranean tree communities in southern France

Abstract

Adopting a multifaceted approach of biodiversity is believed to capture different aspects of the ecosystem functioning and it is thus advised for conservation prioritisation, especially for anthropogenic ecosystems but this key topic has never been conducted for the Mediterranean tree assemblages, despite their ecological importance. We explored how the multi-faceted diversity of woody plant assemblages, as measured by taxonomic (TD), functional (FD) and phylogenetic (PD) diversities, are distributed over space in the French part of the Mediterranean biome, and to which extend they are spatially correlated to each other, in order to understand whether one facet can be used as a proxy for another, especially for conservation management purposes.We analysed data from 5885 plots over the study area. We estimated several FD types by considering separately (i) regeneration, (ii) morphology traits (iii) modalities on species ecological properties, and finally (iv) considering all traits together. We used the Rao quadratic entropy to estimate the TD, FD and PD diversity facets. We tested for the links and spatial correlation (congruence) levels among these facets, using simultaneous autoregressive (SAR) models and partial Mantel tests.Spatial structure varied among diversity facets and spatial autocorrelation patterns were identified for all diversity indices from 30 to 50 km distances. We observed a functional convergence and a phylogenetic divergence within tree assemblages comparing to the ones expected given the regional species pool, indicating that even in tree communities with functional similarities, phylogenetic diversity may be high. PD was zero to slightly congruent to FD, regardless the type of functional traits considered. The highest SAR slope (=0.3) and partial Mantel test (=0.2) were revealed between the PD and the FD based on species morphological traits, but still remained considerably low.Each one of the diversity indicators reflected a different tree community spatial pattern. Functional diversity patterns varied according to the type of traits considered. Using only taxonomic indices may be misleading for responding to Mediterranean tree assemblages conservation needs and additional information about the species phylogeny and functional responses to disturbance pressures should be considered in large scale analyses.

Fish taxonomic, functional, and phylogenetic diversity and their vulnerabilities in the largest river in southeastern China

“…Correlations between different facets of biodiversity are weakened by these factors. Thus, incongruences occurred in many cases on regional scales, and it raised the challenge that trade‐offs were inevitable when protecting multiple biodiversity facets (Doxa et al., 2020 ; Kuczynski et al., 2018 ). This is the case in the Min River, whose mismatches of different facets of biodiversity were correlated with segmented river networks.…”

“…Conservation biologists are interested in PD because maximizing PD is assumed to conserve the most genotypes or phenotypes of different phylogenetic taxa in a community (Veron et al., 2019 ). Many conservation practices try to seek congruence of TD, FD, and PD, aiming to balance the protection of different biodiversity facets at the same time (Doxa et al., 2020 ; Strecker et al., 2011 ; Wong et al., 2018 ).…”

Spatial patterns of genus‐level phylogenetic endemism in the tree flora of Mediterranean Europe

“…Limitations may also arise when considering all species equal entities and ignoring their particular functional role in the ecosystem, their associated communities and/or their evolutionary history (e.g., Doxa et al, 2020).…”

Traits, landmarks and outlines: Three congruent sides of a tale on coral reef fish morphology

“…The highest and lowest values with the corresponding sites are also indicated in the bottom right corner of each map hotspots is one of the most common strategies to conserve biodiversity (Norman & White, 2019). The location of such hotspots may, however, be elusive and context-dependent given that biodiversity is multifaceted and the different facets are not necessarily spatially congruent (Doxa et al, 2020;Tolimieri et al, 2015). The integration of more than one biodiversity metric or a more informed use of the different metrics depending on the particular conservation goals, has been called for (Cadotte & Tucker, 2018;Devictor et al, 2010a;Tolimieri et al, 2015).…”