A multi-faceted comparative perspective on elevational beta-diversity: the patterns and their causes

The observed patterns and underlying mechanisms of elevational beta-diversity have been explored intensively, but multi-dimensional comparative studies remain scarce. Herein, across distinct beta-diversity components, dimensions and species groups, we designed a multi-faceted comparative framework aiming to reveal the general rules in the observed patterns and underlying causes of elevational beta-diversity. We have found that: first, the turnover process dominated altitudinal patterns of species beta-diversity ( β sim > β sne ), whereas the nestedness process appeared relatively more important for elevational trait dissimilarity ( β funcsim < β funcsne ); second, the taxonomic turnover was relative higher than its phylogenetic and functional analogues ( β sim > β phylosim / β funcsim ), conversely, nestedness-resultant trait dissimilarity tended to be higher than the taxonomic and phylogenetic measures ( β funcsne > β sne / β phylosne ); and third, as elevational distance increased, the contradicting dynamics of environmental filtering and limiting similarity have jointly led the elevational patterns of beta-diversity, especially at taxonomic dimension. Based on these findings, we infer that the species turnover among phylogenetic relatives sharing similar functional attributes appears to be the main cause of shaping the altitudinal patterns of multi-dimensional beta-diversity. Owing to the methodological limitation in the randomization approach, currently, it remains extremely challenging to distinguish the influence of the neutral process from the offset between opposing niche-based processes. Despite the complexities and uncertainties during species assembling, with a multi-dimensional comparative perspective, this work offers us several important commonalities of elevational beta-diversity dynamics.

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Co-occurrences of tropical trees in eastern South America: disentangling abiotic and biotic forces

Plant Ecology ◽

10.1007/s11258-021-01143-3 ◽

2021 ◽

Author(s):

Emma-Liina Marjakangas ◽

Otso Ovaskainen ◽

Nerea Abrego ◽

Vidar Grøtan ◽

Alexandre A. de Oliveira ◽

...

Keyword(s):

South America ◽

Tree Species ◽

Large Scale ◽

Environmental Filtering ◽

Limiting Similarity ◽

Phylogenetic Relatedness ◽

Biogeographical Regions ◽

Dependent Processes ◽

Occurrence Of Species

AbstractSpecies co-occurrences in local communities can arise independent or dependent on species’ niches. However, the role of niche-dependent processes has not been thoroughly deciphered when generalized to biogeographical scales, probably due to combined shortcomings of data and methodology. Here, we explored the influence of environmental filtering and limiting similarity, as well as biogeographical processes that relate to the assembly of species’ communities and co-occurrences. We modelled jointly the occurrences and co-occurrences of 1016 tropical tree species with abundance data from inventories of 574 localities in eastern South America. We estimated species co-occurrences as raw and residual associations with models that excluded and included the environmental effects on the species’ co-occurrences, respectively. Raw associations indicate co-occurrence of species, whereas residual associations indicate co-occurrence of species after accounting for shared responses to environment. Generally, the influence of environmental filtering exceeded that of limiting similarity in shaping species’ co-occurrences. The number of raw associations was generally higher than that of the residual associations due to the shared responses of tree species to the environmental covariates. Contrary to what was expected from assuming limiting similarity, phylogenetic relatedness or functional similarity did not limit tree co-occurrences. The proportions of positive and negative residual associations varied greatly across the study area, and we found a significant tendency of some biogeographical regions having higher proportions of negative associations between them, suggesting that large-scale biogeographical processes limit the establishment of trees and consequently their co-occurrences.

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Partitioning the colonization and extinction components of beta diversity: Spatiotemporal species turnover across disturbance gradients

10.1101/2020.02.24.956631 ◽

2020 ◽

Author(s):

Shinichi Tatsumi ◽

Joachim Strengbom ◽

Mihails Čugunovs ◽

Jari Kouki

Keyword(s):

Plant Communities ◽

Beta Diversity ◽

Species Turnover ◽

Single Point ◽

Relative Importance ◽

Dynamic Nature ◽

Colonization Dynamics ◽

Per Se ◽

The Given ◽

Temporal Species Turnover

ABSTRACTChanges in species diversity often result from species losses and gains. The dynamic nature of beta diversity (i.e., spatial variation in species composition) that derives from such temporal species turnover, however, has been largely overlooked. Here, we disentangled extinction and colonization components of beta diversity by using the sets of species that went locally extinct and that newly colonized the given sites. We applied this concept of extinction and colonization beta diversity to plant communities that have been repeatedly measured in experimentally disturbed forests. We first found no difference in beta diversity across disturbance gradients when it was analyzed for communities at a single point in time. From this result, we might conclude that disturbance caused no impact on how species assemble across space. However, when we analyzed the extinction and colonization beta diversity, both measures were found to be significantly lower in disturbed sites compared to undisturbed sites. These results indicate that disturbance removed similar subsets of species across space, making communities differentiate, but at the same time induced spatially uniform colonization of new species, causing communities to homogenize. Consequently, the effects of these two processes canceled each other out. The relative importance of extinction and colonization components per se also changed temporally after disturbance. Analyses using extinction and colonization beta diversity allowed us to detect nonrandom dis- and re-assembly dynamics in plant communities. Our results suggest that common practices of analyzing beta diversity at one point in time can mask significant variation driven by disturbance. Acknowledging the extinction–colonization dynamics behind beta diversity is essential for understanding the spatiotemporal organization of biodiversity.

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Environmental and historical imprints on beta diversity: insights from variation in rates of species turnover along gradients

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.1201 ◽

2013 ◽

Vol 280 (1768) ◽

pp. 20131201 ◽

Cited By ~ 85

Author(s):

Matthew C. Fitzpatrick ◽

Nathan J. Sanders ◽

Signe Normand ◽

Jens-Christian Svenning ◽

Simon Ferrier ◽

...

Keyword(s):

Beta Diversity ◽

Linear Models ◽

Species Turnover ◽

Ecological Systems ◽

Climate History ◽

Northern European ◽

Species Similarity ◽

Southwest Australia ◽

Novel Method ◽

Curvilinear Relationships

A common approach for analysing geographical variation in biodiversity involves using linear models to determine the rate at which species similarity declines with geographical or environmental distance and comparing this rate among regions, taxa or communities. Implicit in this approach are weakly justified assumptions that the rate of species turnover remains constant along gradients and that this rate can therefore serve as a means to compare ecological systems. We use generalized dissimilarity modelling, a novel method that accommodates variation in rates of species turnover along gradients and between different gradients, to compare environmental and spatial controls on the floras of two regions with contrasting evolutionary and climatic histories: southwest Australia and northern Europe. We find stronger signals of climate history in the northern European flora and demonstrate that variation in rates of species turnover is persistent across regions, taxa and different gradients. Such variation may represent an important but often overlooked component of biodiversity that complicates comparisons of distance–decay relationships and underscores the importance of using methods that accommodate the curvilinear relationships expected when modelling beta diversity. Determining how rates of species turnover vary along and between gradients is relevant to understanding the sensitivity of ecological systems to environmental change.

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Taxonomic Dependency of Beta Diversity for Bacteria, Archaea and Fungi in a Semi-Arid Lake

10.21203/rs.3.rs-1120535/v1 ◽

2021 ◽

Author(s):

Haijun Yuan ◽

Weizhen Zhang ◽

Huaqun Yin ◽

Runyu Zhang ◽

Jianjun Wang

Keyword(s):

Water Depth ◽

Beta Diversity ◽

Species Turnover ◽

Environmental Drivers ◽

Ecological Processes ◽

Environmental Selection ◽

Community Variation ◽

Taxonomic Groups ◽

Semi Arid ◽

Total Beta

Abstract Microbial beta diversity has been recently studied along the water depth in aquatic ecosystems, however its turnover and nestedness components remain elusive especially for multiple taxonomic groups. Based on the beta diversity partitioning developed by Baselga and Local Contributions to Beta Diversity (LCBD) partitioning by Legendre, we examined the water-depth variations in beta diversity components of bacteria, archaea and fungi in surface sediments of Hulun Lake, a semi-arid lake in northern China, and further explored the relative importance of environmental drivers underlying their patterns. We found that the relative abundances of Proteobacteria, Chloroflexi, Euryarchaeota and Rozellomycota increased towards deep water, while Acidobacteria, Parvarchaeota and Chytridiomycota decreased. For bacteria and archaea, there were significant (P < 0.05) decreasing water-depth patterns for LCBD and LCBDRepl (i.e., species replacement), while increasing patterns for total beta diversity and turnover, implying that total beta diversity and LCBD were dominated by species turnover or LCBDRepl. Further, bacteria showed a strong correlation with archaea regarding LCBD, total beta diversity and turnover. Such parallel patterns among bacteria and archaea were underpinned by similar ecological processes like environmental selection. Total beta diversity and turnover were largely affected by sediment total nitrogen, while LCBD and LCBDRepl were mainly constrained by water NO2−-N and NO3−-N. For fungal community variation, no significant patterns were observed, which may be due to different drivers like water nitrogen or phosphorus. Taken together, our findings provide compelling evidences for disentangling the underlying mechanisms of community variation in multiple aquatic microbial taxonomic groups.

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Beta Diversity Partitioning and Drivers of Variations in Fish Assemblages in a Headwater Stream: Lijiang River, China

Water ◽

10.3390/w11040680 ◽

2019 ◽

Vol 11 (4) ◽

pp. 680 ◽

Cited By ~ 1

Author(s):

Liangliang Huang ◽

Jian Huang ◽

Zhiqiang Wu ◽

Yuanmin Mo ◽

Qi Zou ◽

...

Keyword(s):

Species Composition ◽

Beta Diversity ◽

Fish Assemblages ◽

Headwater Streams ◽

Species Turnover ◽

Diversity Partitioning ◽

Spatial Variables ◽

Lijiang River ◽

Abiotic Variables ◽

Hydrological Variables

Beta diversity partitioning has currently received much attention in research of fish assemblages. However, the main drivers, especially the contribution of spatial and hydrological variables for species composition and beta diversity of fish assemblages are less well studied. To link species composition to multiple abiotic variables (i.e., local environmental variables, hydrological variables, and spatial variables), the relative roles of abiotic variables in shaping fish species composition and beta diversity (i.e., overall turnover, replacement, and nestedness) were investigated in the upstream Lijiang River. Species composition showed significant correlations with environmental, hydrological, and spatial variables, and variation partitioning revealed that the local environmental and spatial variables outperformed hydrological variables, and especially abiotic variables explained a substantial part of the variation in the fish composition (43.2%). The overall species turnover was driven mostly by replacement (87.9% and 93.7% for Sørensen and Jaccard indices, respectively) rather than nestedness. Mantel tests indicated that the overall species turnover (ßSOR and ßJAC) and replacement (ßSIM and ßJTU) were significantly related to hydrological, environmental, and spatial heterogeneity, whereas nestedness (ßSNE or ßJNE) was insignificantly correlated with abiotic variables (P > 0.05). Moreover, the pure effect of spatial variables on overall species turnover (ßSOR and ßJAC) and replacement (ßSIM and ßJTU), and the pure effect of hydrological variables on replacement (ßSIM and ßJTU), were not important (P > 0.05). Our findings demonstrated the relative importance of interactions among environmental, hydrological, and spatial variables in structuring fish assemblages in headwater streams; these fish assemblages tend to be compositionally distinct, rather than nested derivatives of one another. Our results, therefore, indicate that maintaining natural flow dynamics and habitat continuity are of vital importance for conservation of fish assemblages and diversity in headwater streams.

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Alpha and beta diversity patterns of polychaete assemblages across the nodule province of the eastern Clarion-Clipperton Fracture Zone (equatorial Pacific)

Biogeosciences ◽

10.5194/bg-17-865-2020 ◽

2020 ◽

Vol 17 (4) ◽

pp. 865-886 ◽

Cited By ~ 5

Author(s):

Paulo Bonifácio ◽

Pedro Martínez Arbizu ◽

Lénaïck Menot

Keyword(s):

Fracture Zone ◽

Beta Diversity ◽

Species Turnover ◽

Regional Scale ◽

Equatorial Pacific ◽

Equatorial Pacific Ocean ◽

Species Ranges ◽

Diversity Patterns ◽

Clipperton Fracture Zone ◽

Clarion Clipperton Fracture Zone

Abstract. In the abyssal equatorial Pacific Ocean, most of the seafloor of the Clarion-Clipperton Fracture Zone (CCFZ), a 6 million km2 polymetallic nodule province, has been preempted for future mining. In light of the large environmental footprint that mining would leave and given the diversity and the vulnerability of the abyssal fauna, the International Seabed Authority has implemented a regional management plan that includes the creation of nine Areas of Particular Environmental Interest (APEIs) located at the periphery of the CCFZ. The scientific principles for the design of the APEIs were based on the best – albeit very limited – knowledge of the area. The fauna and habitats in the APEIs are unknown, as are species' ranges and the extent of biodiversity across the CCFZ. As part of the Joint Programming Initiative Healthy and Productive Seas and Oceans (JPI Oceans) pilot action “Ecological aspects of deep-sea mining”, the SO239 cruise provided data to improve species inventories, determine species ranges, identify the drivers of beta diversity patterns and assess the representativeness of an APEI. Four exploration contract areas and an APEI (APEI no. 3) were sampled along a gradient of sea surface primary productivity that spanned a distance of 1440 km in the eastern CCFZ. Between three and eight quantitative box cores (0.25 m2; 0–10 cm) were sampled in each study area, resulting in a large collection of polychaetes that were morphologically and molecularly (cytochrome c oxidase subunit I and 16S genes) analyzed. A total of 275 polychaete morphospecies were identified. Only one morphospecies was shared among all five study areas and 49 % were singletons. The patterns in community structure and composition were mainly attributed to variations in organic carbon fluxes to the seafloor at the regional scale and nodule density at the local scale, thus supporting the main assumptions underlying the design of the APEIs. However, the APEI no. 3, which is located in an oligotrophic province and separated from the CCFZ by the Clarion Fracture Zone, showed the lowest densities, lowest diversity, and a very low and distant independent similarity in community composition compared to the contract areas, thus questioning the representativeness and the appropriateness of APEI no. 3 to meet its purpose of diversity preservation. Among the four exploration contracts, which belong to a mesotrophic province, the distance decay of similarity provided a species turnover of 0.04 species km−1, an average species range of 25 km and an extrapolated richness of up to 240 000 polychaete species in the CCFZ. By contrast, nonparametric estimators of diversity predict a regional richness of up to 498 species. Both estimates are biased by the high frequency of singletons in the dataset, which likely result from under-sampling and merely reflect our level of uncertainty. The assessment of potential risks and scales of biodiversity loss due to nodule mining thus requires an appropriate inventory of species richness in the CCFZ.

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Livestock grazing-induced large-scale biotic homogenization in arid Mediterranean steppe rangelands

10.22541/au.161494226.60674414/v2 ◽

2021 ◽

Author(s):

Merdas Saifi ◽

Yacine Kouba ◽

Tewfik Mostephaoui ◽

Yassine Farhi ◽

Haroun Chenchouni

Keyword(s):

Species Composition ◽

Spatial Scale ◽

Plant Communities ◽

Beta Diversity ◽

Large Scale ◽

Management Practices ◽

Species Turnover ◽

Livestock Grazing ◽

Biotic Homogenization ◽

Arid Steppe

Despite many studies explored the effect of livestock grazing on plant communities, the response of species composition and diversity to livestock grazing in arid rangelands remain ambiguous. This study examined the effects of livestock grazing on plant communities in arid steppe rangelands of North Africa. Plant diversity of annual species, perennial species and all species combined was measured and compared between grazed and grazing-excluded areas. We also examined the relative importance of species turnover and community nestedness. Moreover, the effects of livestock grazing on beta diversity at local among transects and landscape among sites scales were examined using the multiplicative diversity partitioning. Results revealed that livestock grazing significantly decreased the alpha diversity of all species combined and the diversity of annual plants. Livestock grazing induced a shift in plant community composition where most of species composition variation (~74%) was due to infrequent species replacement ‘turnover’ between the two management types rather than nestedness (~26%). Results revealed also that among transects, beta diversity was higher in grazed steppes than in grazing-excluded steppes. Whereas, among sites, beta diversity was lower in grazed steppes compared to grazing-excluded steppes. These findings suggest that livestock grazing in arid steppe rangelands increases the variation in plant species composition at a local spatial scale and engenders vegetation homogeneity at landscape spatial scale. Therefore, the implementation of appropriate management practices such as short-term grazing exclusion is mandatory to prevent these ecosystems from large scale biotic homogenization.

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Identifying the Drivers of Spatial Taxonomic and Functional Beta-Diversity of British Breeding Birds

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.620062 ◽

2021 ◽

Vol 9 ◽

Author(s):

Joseph P. Wayman ◽

Jonathan P. Sadler ◽

Thomas A. M. Pugh ◽

Thomas E. Martin ◽

Joseph A. Tobias ◽

...

Keyword(s):

Land Use ◽

Beta Diversity ◽

Environmental Filtering ◽

Bird Species ◽

Predictor Variable ◽

Dispersal Limitation ◽

Functional Change ◽

Pairwise Distance ◽

Geographical Distance ◽

Human Influence

Spatial variation in community composition may be driven by a variety of processes, including environmental filtering and dispersal limitation. While work has been conducted on the relative importance of these processes on various taxa and at varying resolutions, tests using high-resolution empirical data across large spatial extents are sparse. Here, we use a dataset on the presence/absence of breeding bird species collected at the 10 km × 10 km scale across the whole of Britain. Pairwise spatial taxonomic and functional beta diversity, and the constituent components of each (turnover and nestedness/richness loss or gain), were calculated alongside two other measures of functional change (mean nearest taxon distance and mean pairwise distance). Predictor variables included climate and land use measures, as well as a measure of elevation, human influence, and habitat diversity. Generalized dissimilarity modeling was used to analyze the contribution of each predictor variable to variation in the different beta diversity metrics. Overall, we found that there was a moderate and unique proportion of the variance explained by geographical distance per se, which could highlight the role of dispersal limitation in community dissimilarity. Climate, land use, and human influence all also contributed to the observed patterns, but a large proportion of the explained variance in beta diversity was shared between these variables and geographical distance. However, both taxonomic nestedness and functional nestedness were uniquely predicted by a combination of land use, human influence, elevation, and climate variables, indicating a key role for environmental filtering. These findings may have important conservation implications in the face of a warming climate and future land use change.

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The many forms of beta diversity: a comment on McGill et al. and some notational suggestions

10.7287/peerj.preprints.3157 ◽

2017 ◽

Author(s):

Tobias Jeppsson

Keyword(s):

Spatial Patterns ◽

Beta Diversity ◽

Temporal Trend ◽

Species Turnover ◽

Temporal Trends ◽

Β Diversity ◽

Different Types ◽

Biodiversity Change ◽

The Many

Fundamentally, beta diversity is a measure of species turnover across time or space. In practice, it is sometimes unclear exactly what aspect of beta diversity that is implied in studies. For instance, a trend in ’spatial beta diversity’ can be used to refer to both differences in spatial beta diversity between sites, as well as a temporal trend in spatial beta diversity (at the same site). In a recent review, McGill et al. [1] provide a useful and much needed overview of different aspects of biodiversity change, and show areas where we lack knowledge. Even so, McGill et al. ignore some aspects of beta diversity and sometimes pool different types of beta diversity under the same heading. However, their review mainly focused on temporal trends in diversity, while I here want to highlight spatial patterns in temporal β -diversity (species turnover) as an important but somewhat overlooked component of biodiversity change. Furthermore, I propose a slightly modified classification and nomenclature of metrics of biodiversity change, with the aim of complementing their review. The notation used here can hopefully be useful to other authors as well.

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Ecological theory applied to environmental metabolomes reveals compositional divergence despite conserved molecular properties

10.1101/2020.02.12.946459 ◽

2020 ◽

Cited By ~ 4

Author(s):

Robert E. Danczak ◽

Amy E. Goldman ◽

Rosalie K. Chu ◽

Jason G. Toyoda ◽

Vanessa A. Garayburu-Caruso ◽

...

Keyword(s):

Environmental Filtering ◽

Molecular Properties ◽

Freshwater Ecosystem ◽

Ecological Communities ◽

Ecological Concept ◽

Metacommunity Ecology ◽

Novel Approach ◽

Underlying Mechanisms ◽

Insight Into ◽

Dom Composition

AbstractStream and river systems transport and process substantial amounts of dissolved organic matter (DOM) from terrestrial and aquatic sources to the ocean, with global biogeochemical implications. However, the underlying mechanisms affecting the spatiotemporal organization of DOM composition are under-investigated. To understand the principles governing DOM composition, we leverage the recently proposed synthesis of metacommunity ecology and metabolomics, termed ‘meta-metabolome ecology.’ Applying this novel approach to a freshwater ecosystem, we demonstrated that despite similar molecular properties across metabolomes, metabolite identity significantly diverged due to environmental filtering. We refer to this phenomenon as ‘thermodynamic redundancy,’ which is analogous to the ecological concept of functional redundancy. We suggest that under thermodynamic redundancy, divergent metabolomes can support equivalent biogeochemical function just as divergent ecological communities can support equivalent ecosystem function. As these analyses are performed in additional ecosystems, potentially generalizable principles, like thermodynamic redundancy, can be revealed and provide insight into DOM dynamics.

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