Global patterns of taxonomic and phylogenetic diversity of flowering plants: Biodiversity hotspots and coldspots

Species diversity of angiosperms(flowering plants) varies greatly among regions.Geographic patterns of variation in species diversity are shaped by the interplay of ecological and evolutionary processes.Here,using a comprehensive data set for regional angiosperm floras across the world,we show geographic patterns of taxonomic(species) diversity,phylogenetic diversity,phylogenetic dispersion,and phylogenetic deviation(i.e.,phylogenetic diversity after accounting for taxonomic diversity) across the world.Phylogenetic diversity is strongly and positively correlated with taxonomic diversity;as a result,geographic patterns of taxonomic and phylogenetic diversity across the world are highly similar.Areas with high taxonomic and phylogenetic diversity are located in tropical regions whereas areas with low taxonomic and phylogenetic diversity are located in temperate regions,particularly in Eurasia and North America,and in northern Africa.Similarly,phylogenetic dispersion is,in general,higher in tropical regions and lower in temperate regions.However,the geographic pattern of phylogenetic deviation differs substantially from those of taxonomic and phylogenetic diversity and phylogenetic dispersion.As a result,hotspots and coldspots of angiosperm diversity identified based on taxonomic and phylogenetic diversity and phylogenetic dispersion are incongruent with those identified based on phylogenetic deviations.Each of these metrics may be considered when selecting areas to be protected for their biodiversity.

Phylogenetic diversity of eastern Asia-eastern North America disjunct plants is mainly associated with divergence time

The underlying causes of biodiversity disparities among geographic regions have long been a fundamental theme in ecology and evolution.However,the patterns of phylogenetic diversity(PD) and phylogenetic beta diversity(PBD) of congeners that are disjunctly distributed between eastern Asia-eastern North America(EA-ENA disjuncts) and their associated factors remain unknown.Here we investigated the standardized effect size of PD(SES-PD),PBD,and potentially associated factors in 11natural mixed forest sites(five in EA and six in ENA) where abundant EA-ENA disjuncts occur.We found that the disjuncts in ENA possessed higher SES-PD than those in EA at the continental scale(1.96vs-1.12),even though the number of disjunct species in ENA is much lower than in EA(128 vs 263).SESPD of the EA-ENA disjuncts tended to decrease with increasing latitude in 11 sites.The latitudinal diversity gradient of SES-PD was stronger in EA sites than in ENA sites.Based on the unweighted unique fraction metric(UniFrac) distance and the phylogenetic community dissimilarity,PBD showed that the two northern sites in EA were more similar to the six-site ENA group than to the remaining southern EA sites.Based on the standardized effect size of mean pairwise distances(SES-MPD),nine of eleven studied sites showed a neutral community structure(-1.96 ≤SES-MPD ≤1.96).Both Pearson’s r and structural equation modeling suggested that SES-PD of the EA-ENA disjuncts was mostly associated with mean divergence time.Moreover,SES-PD of the EA-ENA disjuncts was positively correlated with temperaturerelated climatic factors,although negatively correlated with mean diversification rate and community structure.By applying approaches from phylogenetics and community ecology,our work sheds light on historical patterns of the EA-ENA disjunction and paves the way for further research.

Amphibian Species Contribute Similarly to Taxonomic, but not Functional and Phylogenetic Diversity: Inferences from Amphibian Biodiversity on Emei Mountain

Understanding the relationships between species, communities, and biodiversity are important challenges in conservation ecology. Current biodiversity conservation activities usually focus on species that are rare, endemic, distinctive, or at risk of extinction. However, empirical studies of whether such species contribute more to aspects of biodiversity than common species are still relatively rare. The aim of the present study was to assess the contribution of individual amphibian species to different facets of biodiversity, and to test whether species of conservation interest contribute more to taxonomic, functional, and phylogenetic diversity than do species without special conservation status. To answer these questions, 19 000 simulated random communities with a gradient of species richness were created by shuffling the regional pool of species inhabiting Emei Mountain. Differences of diversity values were then computed before and after removing individual species in these random communities. Our results indicated that although individual species contributed similarly to taxonomic diversity, their contribution to functional and phylogenetic diversity was more idiosyncratic. This was primarily driven by the diverse functional attributes of species and the differences in phylogenetic relationships among species. Additionally, species of conservation interest did not show a significantly higher contribution to any facet of biodiversity. Our results support the claims that the usefulness of metrics based only on species richness is limited. Instead, assemblages that include species with functional and phylogenetic diversity should be protected to maintain biodiversity.

Phylogenetic diversity of bacteria associated with the marine sponge Agelas robusta from South China Sea

It is well known that marine sponges harbor large numbers of bacteria,some of which have been proved to be sponge-specific.The diversity of bacteria in marine sponges distributed along the coast of South China Sea has been previously studied but that of bacteria in sponges inhabiting the open sea has been rarely investigated.In this report,the diversity of bacteria associated with the marine sponge Agelas robusta from a remote coral reef in the South China Sea was documented employing 16S rDNA library construction,amplified ribosomal DNA restriction analysis（ARDRA） and phylogenetic analysis.A total of 32 phylotypes were finally categorized in nine phyla including Cyanobacteria,Proteobacteria,Chloroflexi,Firmicutes,Actinobacteria,Acidobacteria,Planctomycetes,Bacteroidetes and Gemmatimonadetes.The dominant phylum was Proteobacteria whereas the dominant genus was Synechococcus in Cyanobacteria.Some spongespecific bacteria were also found in the bacteria population,but the proportion（5 OTUs/32 OTUs） was much lower than other sponges.This study reveals the phylogenetic diversity of bacteria in A.robusta and confirms the presence of some sponge-specific bacteria in the South China Sea.Understanding the diversity of sponge-associated bacteria in China assists to exploit the bacteria resources for biotechnology.

Phylogenetic diversity of culturable bacteria in surface seawater from the Drake Passage,Antarctica

The Drake Passage is located between the Antarctic Peninsula and Tierra del Fuego in the south of South America.Surface seawater samples were collected at seven sites in the Drake Passage during the austral summer of 2012.The 16 S rRNA sequences were analyzed from 187 isolated bacterial strains.Three phyla,29 genera and 56 species were identified.The three phyla were Actinobacteria,Firmicutes and Proteobacteria;the Proteobacteria included a-Proteobacteria,P-Proteobacteria and y-Proteobacteria.y-Proteobacteria,Actinobacteria and Firmicutes were the dominant class or phyla in terms of quantity and species.Gram-positive bacteria(Actinobacteria and Firmicutes) accounted for 57.8% of all types identified.There were nine dominant genera,including Curtobacterium,Staphylococcus,and Halomonas,and 14 dominant species including Curtobacterium flaccumfaciens,Curtobacterium pusillum,and Staphylococcus sciuri.Of the strains identified,87.2% were catalase positive or weakly positive.

Phylogenetic diversity and bioactivity of culturable deepsea-derived fungi from Okinawa Trough

Deep-sea sediments are now recognized as a home for rich and largely microbial community.Recently,it has been believed in an increasing number of studies that bacteria could be abundant in deepsea sediments of many types;however,fungi in deep-sea sediments remain relatively unknown.The phylogenetic diversity and bioactivity of culturable deep-sea-derived fungi from Okinawa Trough sediments were investigated in traditional method combined with fungal identification of molecular biology in this study.A total of 76 isolates belonged to 15 fungal taxa were recovered in a harsh condition of low nutrient and low temperature,indicating that the fungal communities in deep-sea sediments from Okinawa Trough were relatively abundant and diversified.Aspergillus,Cladosporium,and Penicillium were the dominant fungal genera,while Mycosphaerella,Purpureocillium,and Schizophyllum were relatively rare in the deep-sea sediments from Okinawa Trough.Among the six genera recovered,Mycosphaerella was firstly recovered from deep-sea sediments in this study.Moreover,about 75%of the extracts from the 15 fungal representative isolates displayed distinct bioactivity against at least one indicator bacterium or marine macrofouler,emphasizing the potentials of these deep-sea-derived fungi from Okinawa Trough as producers of bioactive metabolites.Notably,isolates Cladosporium oxysporum SCSIO z001 and Penicillium citrinum SCSIO z049 displayed a wide spectrum of bioactivities,isolates Cladosporium cladosporioides SCSIO z015,Cladosporium sphaerospermum SCSIO z030,and Penicillium verruculosum SCSIO z007 exhibited a strong anti-bacterial-growth activity,and isolate Penicillium chrysogenum SCSIO z062 displayed a strong anti-larval-settlement activity.These results suggest that these isolates deserved further study as potential sources of novel bioactive metabolites.

Opposite latitudinal gradients for species richness and phylogenetic diversity of endemic snakes in the Atlantic Forest

The decrease in species richness toward higher latitudes is an expected biogeographical pattern.This pattern could be related to particular envi-ronmental constraints and the evolutionary history of clades.However,species richness does not fully represent the evolutionary history of the clades behind their distributions.Phylogenetic diversity better clarifies the role of historical factors in biogeographical patterns.We analyzed envi-ronmental and historical drivers related to latitudinal variation in species richness and phylogenetic diversity of Atlantic Forest endemic snakes.We implemented species distribution models,from voucherbased locality points,to map the snake ranges and diversity.We used generalized additive mixed models to evaluate the relationships among the diversity metrics and area,topographical roughness,and past climate change velocity since the Last Maximum Glacial in the Atlantic Forest latitudinal gradient.Contrary to the expected general pattern,species richness was higher toward higher latitudes,being positively related to past climatic stability.Species richness also increased with total area and higher topographical roughness.Phylogenetic diversity,on the other hand,showed opposite relationships related to the same factors.Phylogenetic diversity increased with lower climatic stability in lower latitudes.Thus,dimensions of diversity were affected in different ways by historical and environmental constraints in this unique and threatened biodiversity hotspot.

A phylogenetic approach identifies patterns of beta diversity and floristic subregions of the Qinghai-Tibet Plateau

Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional biota.The Qinghai-Tibet Plateau(QTP)harbors an exceptionally diverse flora,however,a phylogenetic perspective has rarely been used to investigate its beta diversity and floristic regions.In this study,we used a phylogenetic approach to identify patterns of beta diversity and quantitatively delimit floristic regions on the Qinghai-Tibet Plateau.We also examined the relationships between multifaceted beta diversity,geographical distance,and climatic difference,and evaluated the relative importance of various factors(i.e.,climate,topography and history)in shaping patterns of beta diversity.Sørensen dissimilarity indices indicated that patterns of species turnover among sites dominated the QTP.We also found that patterns of both taxonomic and phylogenetic beta diversity were significantly related to geographical distance and climatic difference.The environmental factors that contributed most to these patterns of beta diversity include annual precipitation,mean annual temperature,climatic gradients and climatic instability.Hierarchical dendrograms of dissimilarity and non-metric multidimensional scaling ordination based on phylogenetic beta diversity data identified ten floristic subregions in the QTP.Our results suggest that the contemporary environment and historical climate changes have filtered species composition among sites and eventually determined beta diversity patterns of plants in the QTP.

Global patterns of phylogenetic diversity and transmission of bat coronavirus

Bats are reservoirs for multiple coronaviruses(Co Vs).However,the phylogenetic diversity and transmission of global bat-borne Co Vs remain poorly understood.Here,we performed a Bayesian phylogeographic analysis based on 3,594 bat Co V Rd Rp gene sequences to study the phylogenetic diversity and transmission of bat-borne Co Vs and the underlying driving factors.We found that host-switching events occurred more frequently forα-Co Vs than forβ-Co Vs,and the latter was highly constrained by bat phylogeny.Bat species in the families Molossidae,Rhinolophidae,Miniopteridae,and Vespertilionidae had larger contributions to the cross-species transmission of bat Co Vs.Regions of eastern and southern Africa,southern South America,Western Europe,and Southeast Asia were more frequently involved in cross-region transmission events of bat Co Vs than other regions.Phylogenetic and geographic distances were the most important factors limiting Co V transmission.Bat taxa and global geographic hotspots associated with bat Co V phylogenetic diversity were identified,and bat species richness,mean annual temperature,global agricultural cropland,and human population density were strongly correlated with the phylogenetic diversity of bat Co Vs.These findings provide insight into bat Co Vevolution and ecological transmission among bat taxa.The identified hotspots of bat Co V evolution and transmission will guide early warnings of bat-borne Co V zoonotic diseases.

Evolutionary fingerprint, phylogenetic and forest structure of tropical montane Atlantic cloud forests along an elevation gradient

Environmental conditions can change markedly over geographical distances along elevation gradients,making them natural laboratories to study the processes that structure communities.This work aimed to assess the influences of elevation on Tropical Montane Cloud Forest plant communities in the Brazilian Atlantic Forest,a historically neglected ecoregion.We evaluated the phylogenetic structure,forest structure(tree basal area and tree density)and species richness along an elevation gradient,as well as the evolutionary fingerprints of elevation-success on phylogenetic lineages from the tree communities.To do so,we assessed nine communities along an elevation gradient from 1210 to 2310 m a.s.l.without large elevation gaps.The relationships between elevation and phylogenetic structure,forest structure and species richness were investigated through Linear Models.The occurrence of evolutionary fingerprint on phylogenetic lineages was investigated by quantifying the extent of phylogenetic signal of elevation-success using a genus-level molecular phylogeny.Our results showed decreased species richness at higher elevations and independence between forest structure,phylogenetic structure and elevation.We also verified that there is a phylogenetic signal associated with elevation-success by lineages.We concluded that the elevation is associated with species richness and the occurrence of phylogenetic lineages in the tree communities evaluated in Mantiqueira Range.On the other hand,elevation is not associated with forest structure or phylogenetic structure.Furthermore,closely related taxa tend to have their higher ecological success in similar elevations.Finally,we highlight the fragility of the tropical montane cloud forests in the Mantiqueira Range in face of environmental changes(i.e.global warming)due to the occurrence of exclusive phylogenetic lineages evolutionarily adapted to environmental conditions(i.e.minimum temperature)associated with each elevation range.

No generality in biodiversity-productivity relationships along elevation in temperate and subtropical forest landscapes

An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis suggests that BPRs are stronger in stressful environments compared to more favorable conditions.However,there is limited knowledge regarding the variation of BPRs along elevational gradients and their generality across different landscapes.To study how BPRs change with elevation,we harnessed inventory data on 6,431 trees from152 plots surveyed twice in eight to ten year intervals in mountain forests of temperate Europe and subtropical Asia.We quantified the relationship between aboveground productivity and different biodiversity measures,including taxonomic,functional,and phylogenetic diversity.To elucidate the processes underlying BPRs,we studied the variation of different functional traits along elevation across landscapes.We found no general pattern of BPRs across landscapes and elevations.Relationships were neutral for all biodiversity measures in temperate forests,and negative for taxonomic and functional diversity in subtropical forests.BPRs were largely congruent between taxonomic,functional and phylogenetic diversity.We found only weak support for the stress-gradient hypothesis,with BPRs turning from negative to positive(effect not significant)close to the tree line in subtropical forests.In temperate forests,however,elevation patterns were strongly modulated by species identity effects as influenced by specific traits.The effect of traits such as community-weighted mean of maximum plant height and wood density on productivity was congruent across landscapes.Our study highlights the context-dependence of BPRs across elevation gradients and landscapes.Species traits are key modulating factors of BPRs and should be considered more explicitly in studies of the functional role of biodiversity.Furthermore,our findings highlight that potential trade-offs between conserving biodiversity and fostering ecosystem productivity exist,which require more attention in policy and management.

Diversity and interactions of lichen mycobionts and photobionts in the Fildes Region, King George Island, maritime Antarctica

Lichens,as dual organisms comprising a major mycobiont and a major photobiont,exhibit remarkable survival capabilities in extreme conditions,such as those found in Antarctica.Despite their adaptability,the diversity and distribution of lichen photobionts in the ice-free areas of maritime Antarctica remain less understood compared to their mycobiont counterparts.In our study,we investigated the diversity of both lichen mycobionts and photobionts in 56 samples collected from the Fildes Region on King George Island,maritime Antarctica.Through sequencing of the nuclear ribosomal internal transcribed spacer regions and subsequent phylogenetic analysis,we examined the relationships and association patterns between mycobionts and photobionts.Our findings revealed 19 taxa of lichen mycobionts across 13 families and seven orders,along with nine photobiont species within the class Trebouxiophyceae.These photobionts encompassed six Trebouxia species,one Asterochloris species,one Chloroidium species,and one Stichococcus species.In particular,a new Trebouxia lineage(Trebouxia sp.OTU D08)and a new Chloroidium lineage were found.The analysis indicated that many mycobionts could be associated with multiple photobiont species,a pattern also observed among the photobionts.These results contribute significantly to our understanding of the complex diversity of lichen mycobionts and photobionts in the ice-free areas of maritime Antarctica.

Diversity patterns and phylogenetic structure of vascular plants along elevational gradients in a mountain ecosystem, South Korea

Recently, a phylogenetic diversity and community structure analysis as complementary to species-centric approaches in biodiversity studies provides new insights into the processes of community assembly. In this study, we analyzed species and phylogenetic diversity and community structures for woody and herbaceous plants along two elevational transects on Mt. Baekhwa, South Korea. The species richness and phylogenetic diversity of woody plants showed monotonic declining patterns with increasing elevation along all transects, whereas herbaceous plants showed different patterns, such as no relationship and a reversed unimodal pattern, between the study transects. The main drivers of these patterns were climate and habitat variables for woody and herbaceous plants, respectively. In addition, the phylogenetic community structure primarily showed phylogenetic clustering regulated by deterministic processes, especially environmental filtering, such as climate or habitat factors, along the two transects, although herbaceous plants along a transect depicted phylogenetic randomness as a result of a neutral process. Our findings suggest that deterministic and neutral processes may simultaneously control the community structures along small-scale elevational gradients such as local transects, although the deterministic process may be the predominant type.

How do altitude and soil properties influence the taxonomic and phylogenetic structure and diversity of Brazilian páramo vegetation?

Altitude and environmental variables such as edaphic properties are considered determinants of species distribution and community composition in mountain ecosystems.Here,we aimed to outline the effects of distinct mountain peaks,altitude and soil properties on community composition,species density,phylogenetic structure and diversity of angiosperm páramo communities from the Serra do Brigadeiro State Park,Minas Gerais,southeastern Brazil.For that,we identified all angiosperm species found in 300 plots(1 m×1 m)from three mountain peaks,measured soil depth and analyzed soil fertility and texture in each plot.To reduce the number of soil variables and species composition,we computed principal coordinates based on soil properties and principal coordinates based on species-plot matrix for each plot.Furthermore,we computed the standard effect sizes of the mean phylogenetic pairwise distance and the mean nearest phylogenetic taxon distance for each plot to investigate differences in the degree of relatedness among coexisting species.We compared differences in response variables between peaks and modelled them in function of altitude and principle components of soil properties using mixed effect models.Species density and phylogenetic diversity differed between peaks,but,contrary to the previous findings,no relationships between species richness or phylogenetic diversity and altitude or soil properties were found,indicating that further investigations are necessary to understand the altitude-biodiversity relationship in Brazilian páramo vegetation.Community composition differed between peaks and depended on altitude,soil properties and interactions between them,indicating that upward shifting of bioclimatic conditions due to climate changes may alter communities of this ecosystem.Phylogenetic structure differed between peaks and was influenced by altitude and soil properties.As phylogenetic clustering increased with altitude,eventual upward movements of species in Brazilian páramo vegetation due to climate change may alter community composition and the degree of relatedness among coexisting species,increasing the risk of species from higher altitudes to disappear.Therefore,conservation priorities arise for higher landscape portions,where these high altitude species may find refuges.

Phylogenetic diversity stabilizes community biomass

Aims The relationship between biodiversity and ecological stability is a long-standing issue in ecology.Current diversity–stability studies,which have largely focused on species diversity,often report an increase in the stability of aggregate community properties with increasing species diversity.Few studies have examined the linkage between phylogenetic diversity,another important dimension of biodiversity,and stability.By taking species evolutionary history into account,phylogenetic diversity may better capture the diversity of traits and niches of species in a community than species diversity and better relate to temporal stability.In this study,we investigated whether phylogenetic diversity could affect temporal stability of community biomass independent of species diversity.Methods We performed an experiment in laboratory microcosms with a pool of 12 bacterivorous ciliated protist species.To eliminate the possibility of species diversity effects confounding with phylogenetic diversity effects,we assembled communities that had the same number of species but varied in the level of phylogenetic diversity.Weekly disturbance,in the form of short-term temperature shock,was imposed on each microcosm and species abundances were monitored over time.We examined the relationship between temporal stability of community biomass and phylogenetic diversity and evaluated the role of several stabilizing mechanisms for explaining the influence of phylogenetic diversity on temporal stability.Important Findings Our results showed that increasing phylogenetic diversity promoted temporal stability of community biomass.Both total community biomass and summed variances showed a U-shaped relationship with phylogenetic diversity,driven by the presence of large,competitively superior species that attained large biomass and high temporal variation in their biomass in both low and high phylogenetic diversity communities.Communities without these species showed patterns consistent with the reduced strength of competition and increasingly asynchronous species responses to environmental changes under higher phylogenetic diversity,two mechanisms that can drive positive diversity–stability relationships.These results support the utility of species phylogenetic knowledge for predicting ecosystem functions and their stability.

Community phylogenetic diversity and abiotic site characteristics influence abundance of the invasive plant Rhamnus cathartica L.

Aims Theory predicts that the success of introduced species is related to the diversity of native species through trait-based processes.Abiotic site characteristics may also affect a site’s susceptibility to invasion.We quantified resident plant species richness,phylogenetic diversity and several abiotic site characteristics for 24 oak forests in Minnesota,USA,to assess their impact on the abundance of a widespread,introduced terrestrial plant species,common buckthorn(Rhamnus cathartica L.).Specifically,we asked(1)whether resident species richness and phylogenetic diversity affected the abundance of R.cathartica and(2)what site characteristics explained the overall abundance of R.cathartica.Methods Our survey included 24 oak-dominated stands in Minnesota’s deciduous forests.In each stand,we identified all species in 16 plots.We also measured a series of environmental site characteristics,including canopy openness(a proxy for light availability),percent bare soil,soil pH,percent sand,an index of propagule availability,duff layer thickness(a proxy for earthworm activity),an index of insolation and slope.For all species present in at least one site,we estimated a community phylogeny.We combined all sitelevel characteristics,including phylogenetic diversity of the resident plant species,in a multiple regression model to examine site-level drivers of community invasibility.Important Findings Results indicate that sites with higher overall plant phylogenetic diversity harbor less R.cathartica,even though native species richness was not significantly related to R.cathartica abundance.Regression analyses indicated that,in addition to resident species phylogenetic diversity,the most important predictors of R.cathartica abundance were canopy openness and the amount of bare soil,both positively related to the abundance of the invader.By combining the effects of abiotic site characteristics and resident species phylogenetic diversity in a model that predicted the abundance of R.cathartica,we were able to simultaneously account for a wide range of factors that might influence invasibility.Overall,our results suggest that management strategies aimed at reducing disturbances that lead to increased bare soil and light levels may be more successful if they also maximize phylogenetic diversity of the resident plant community.

The effects of evolutionary and environmental variance on estimates of phylogenetic diversity in temperate forest plots

Aims Phylogenetic diversity metrics can discern the relative contributions of ecological and evolutionary processes associated with the assembly of plant communities.However,the magnitude of the potential variation associated with phylogenetic methodologies,and its effect on estimates of phylogenetic diversity,remains poorly understood.Here,we assess how sources of variation associated with estimates of phylogenetic diversity can pote ntially affect our understanding of plant community structure for a series of temperate forest plots in China.Methods In total,20 forest plots,comprising of 274 woody species and 581 herbaceous species,were surveyed and sampled along an elevational gradient of 2800 m on Taibai Mountain,China.We used multi-model inference to search for the most parsimonious relationship between estimates of phylogenetic diversity and each of four predictors(i.e.type of phylogenetic reconstruction method,phylogenetic diversity metric,woody or herbaceous growth form and elevation),and their pairwise interactions.Important Findings There was nosignificant difference in patterns of phylogenetic diversity when using synthesis-based vs.molecular-based phylogenetic methods.Results showed that elevation,the type of phylogenetic diversity metric,growth form and their interactions,accounted for>44% of the variance in our estimates of phylogenetic diversity.In general,phylogenetic diversity decreased with increasing elevation;however,the trend was weaker for herbaceous plants than for woody plants.Moreover,the three phylogenetic diversity metrics showed consistent patterns(i.e.clustered)across the elevational gradient for woody plants.For herbaceous plants,the mean pairwise distanee showed a random distribution over the gradient.These results suggest that a better understanding of temperate forest comunity structure can be obtained when estimates of phylogenetic diversity include methodological and environmental sources of variation.

Impact of agricultural landscape structure on the patterns of bird species diversity at a regional scale

The loss of bird species diversity is a crucial problem in the European agricultural landscape.Change in the area coverage of major land cover types has been mentioned as one of the main factors responsible for bird biodiversity impoverishment.In this study,we focused on the impact of landscape matrix characteristics on bird species richness and on Faith’s phylogenetic diversity index on a spatial scale of 1000-m radius around the measured occurrence points.We investigated how land cover composition affects bird diversity on the landscape scale using nationwide citizen science data.In total,168,739 records of bird occurrence in the South Moravian Region of the Czech Republic during growing season from 2009 to 2019 were evaluated.We found that the presence of water bodies and wetlands significantly corresponded to the areas of highest bird species richness.We also revealed that the presence of forests(~60%of the forest in the Czech Republic is occupied by commercial forests),urban areas and arable land were negatively associated with bird species richness and phylogenetic diversity.Forests(both coniferous and deciduous)and urban habitats were found to have a tendency to host a clustered phylogenetic community structure in comparison with wetland and arable land.A strong negative association between forest proportion and bird diversity led us to conclude that the expansion of the forest(with simple species composition,horizontal and vertical structure)could be one of the critical drivers of the decline of bird species diversity in the European agricultural landscape.On the other hand,our results also pointed out that small woody features(i.e.,woodlots)and scattered woodland shrub vegetation were one of the main landscape characteristics supporting a bird diversity in rural landscape.This is in concordance with other studies which mention these landscape structures as important elements for nesting and foraging of farmland birds.We thus recommend to maintain and restore scattered trees or woodlots with complex structure in agricultural landscape.

Phylogenetic structure and phylogenetic diversity of angiosperm assemblages in forests along an elevational gradient in Changbaishan,

Aims Understanding what drives the variation in species composition and diversity among local communities can provide insights into the mechanisms of community assembly.Because ecological traits are often thought to be phylogenetically conserved,there should be patterns in phylogenetic structure and phylogenetic diversity in local communities along ecological gradients.We investigate potential patterns in angiosperm assemblages along an elevational gradient with a steep ecological gradient in Changbaishan,China.Methods We used 13 angiosperm assemblages in forest plots(32×32 m)distributed along an elevational gradient from 720 to 1900 m above sea level.We used Faith’s phylogenetic diversity metric to quantify the phylogenetic alpha diversity of each forest plot,used the net relatedness index to quantify the degree of phylogenetic relatedness among angiosperm species within each forest plot and used a phylogenetic dissimilarity index to quantify phylogenetic beta diversity among forest plots.We related the measures of phylogenetic structure and phylogenetic diversity to environmental(climatic and edaphic)factors.Important Findings Our study showed that angiosperm assemblages tended to be more phylogenetically clustered at higher elevations in Changbaishan.This finding is consistent with the prediction of the phylogenetic niche conservatism hypothesis,which highlights the role of niche constraints in governing the phylogenetic structure of assemblages.Our study also showed that woody assemblages differ from herbaceous assemblages in several major aspects.First,phylogenetic clustering dominated in woody assemblages,whereas phylogenetic overdispersion dominated in herbaceous assemblages;second,patterns in phylogenetic relatedness along the elevational and temperature gradients of Changbaishan were stronger for woody assemblages than for herbaceous assemblages;third,environmental variables explained much more variations in phylogenetic relatedness,phylogenetic alpha diversity and phylogenetic beta diversity for woody assemblages than for herbaceous assemblages.

Diversity patterns of cushion plants on the Qinghai-Tibet Plateau:A basic study for future conservation efforts on alpine ecosystems

The Qinghai-Tibet Plateau(QTP)is an important cushion plant hotspot.However,the distribution of cushion plants on the QTP is unknown,as are the factors that drive cushion plant distribution,limiting our understanding of the evolution of cushion species in the region.In this study,we assessed spatial patterns of total cushion plant diversity(including taxonomic and phylogenetic)over the entire QTP and compared patterns of diversity of cushion plants with different typologies(i.e.,compact vs.loose).We also examined how these patterns were related to climatic features.Our results indicate that the southern QTP hosts the highest total cushion plant richness,especially in the south-central Hengduan Mountains subregion.The total number of cushion species declines from south to north and from southeast to northwest.Compact cushion plants exhibit similar patterns as the total cushion plant richness,whereas loose cushion plants show random distribution.Cushion plant phylogenetic diversity showed a similar pattern as that of the total cushion plant richness.In addition,cushion plant phylogenetic community structure was clustered in the eastern and southwestern QTP,whereas random or overdispersed in other areas.Climatic features represented by annual energy and water trends,seasonality and extreme environmental factors,had significant effects on cushion plant diversity patterns but limited effects on the phylogenetic community structure,suggesting that climatic features indeed promote the formation of cushion plants.Because cushion plants play vital roles in alpine ecosystems,our findings not only promote our understanding of the evolution and formation of alpine cushion plant diversity but also provide an indispensable foundation for future studies on cushion plant functions and thus alpine ecosystem sustainability in the entire QTP region.