Species Richness, Functional Diversity and Assemblage Structure of Insectivorous Bats Along an Elevational Gradient in Tropical West Africa

Elevational variation of vegetation has been of interest for centuries, and a prominent example for such pronounced vegetation changes can be found along the steep elevational gradient on Tenerife, Canary Islands, 200 km off the West-African cost. The 3,718-m ascent to the peak of the island volcano, Teide, offers a unique opportunity to investigate associated changes in vegetation. However, elevation is not a directly acting factor, but represents several natural environmental gradients. While the elevational variation of temperature is globally rather uniform and temperature effects on plant communities are well understood, much less is known about the region-specific elevational change of chemical soil properties and their impact on plant communities along elevational gradients. Because human interference takes place even at high-elevation areas, we considered human-induced disturbance as important third factor acting upon plant community assemblages. In our study, we compared the effects of soil properties, temperature and disturbance on species richness, functional identity and functional diversity of plant communities along the elevational gradient on Tenerife. We used pairs of study plots: directly adjacent to a road and in natural vegetation close by. In each plot, we did vegetation relevées, took soil samples, and installed temperature loggers. Additionally, we collected leaf samples to measure leaf functional traits of 80% of the recorded species. With increasing elevation, soil cation concentrations, cation exchange capacity (CEC) and pH decreased significantly, while the soil carbon to phosphorus ratio slightly peaked at mid-elevations. Temperature had the strongest effects, increasing species richness and favoring communities with fast resource acquisition. Species richness was higher at road verges, indicating the positive effect of reduced competition and artificially generated heterogeneity. However, we did not detect road effects on plant functional characteristics. Vice versa, we did not find soil effects on species richness, but increased concentrations of soil cations favored acquisitive communities. Surprisingly, we could not reveal any influence on community functional diversity. The importance of temperature aligns with findings from large-scale biogeographic studies. However, our results also emphasize that it is necessary to consider the effects of local abiotic drivers, like soil properties and disturbance, to understand variation in plant communities.

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Functional evenness of bird communities varies along the elevational gradient in Europe: Conservation implications

10.32942/osf.io/sx9n8 ◽

2019 ◽

Author(s):

Federico Morelli ◽

Yanina

Keyword(s):

Species Richness ◽

Elevation Gradient ◽

Bird Species ◽

Elevational Gradient ◽

Negative Association ◽

Bird Communities ◽

Breeding Bird ◽

Bird Species Richness ◽

Large Spatial Scale ◽

Functional Evenness

ContextThe negative association between elevation and species richness is a well-recognized pattern in macro-ecology. ObjectivesThe aim of this study was to investigate changes in functional evenness of breeding bird communities along an elevation gradient in Europe. MethodsUsing the bird data from the EBCC Atlas of European Breeding Birds we estimated an index of functional evenness which can be assumed as a measure of the potential resilience of communities.ResultsOur findings confirm the existence of a negative association between elevation and bird species richness in all European eco regions. However, we also explored a novel aspect of this relationship, important for conservation: Our findings provide evidence at large spatial scale of a negative association between the functional evenness (potential community resilience) and elevation, independent of the eco region. We also found that the Natura2000 protected areas covers the territory most in need of protection, those characterized by bird communities with low potential resilience, in hilly and mountainous areas.ConclusionsThese results draw attention to European areas occupied by bird communities characterized by a potential lower capacity to respond to strong ecological changes, and, therefore, potentially more exposed to risks for conservation.

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Drivers of ground-dwelling arthropod species richness and assemblage structure in the savannah biome

10.1603/ice.2016.111455 ◽

2016 ◽

Author(s):

Colin Schoeman

Keyword(s):

Species Richness ◽

Assemblage Structure ◽

Arthropod Species

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The Effect of Climate and Human Pressures on Functional Diversity and Species Richness Patterns of Amphibians, Reptiles and Mammals in Europe

Diversity ◽

10.3390/d13060275 ◽

2021 ◽

Vol 13 (6) ◽

pp. 275

Author(s):

Mariana A. Tsianou ◽

Maria Lazarina ◽

Danai-Eleni Michailidou ◽

Aristi Andrikou-Charitidou ◽

Stefanos P. Sgardelis ◽

...

Keyword(s):

Species Richness ◽

Functional Diversity ◽

Agricultural Land ◽

Influential Factor ◽

Climatic Variables ◽

Quadratic Entropy ◽

Functional Richness ◽

Precipitation Seasonality ◽

Rao’S Quadratic Entropy ◽

Richness Patterns

The ongoing biodiversity crisis reinforces the urgent need to unravel diversity patterns and the underlying processes shaping them. Although taxonomic diversity has been extensively studied and is considered the common currency, simultaneously conserving other facets of diversity (e.g., functional diversity) is critical to ensure ecosystem functioning and the provision of ecosystem services. Here, we explored the effect of key climatic factors (temperature, precipitation, temperature seasonality, and precipitation seasonality) and factors reflecting human pressures (agricultural land, urban land, land-cover diversity, and human population density) on the functional diversity (functional richness and Rao’s quadratic entropy) and species richness of amphibians (68 species), reptiles (107 species), and mammals (176 species) in Europe. We explored the relationship between different predictors and diversity metrics using generalized additive mixed model analysis, to capture non-linear relationships and to account for spatial autocorrelation. We found that at this broad continental spatial scale, climatic variables exerted a significant effect on the functional diversity and species richness of all taxa. On the other hand, variables reflecting human pressures contributed significantly in the models even though their explanatory power was lower compared to climatic variables. In most cases, functional richness and Rao’s quadratic entropy responded similarly to climate and human pressures. In conclusion, climate is the most influential factor in shaping both the functional diversity and species richness patterns of amphibians, reptiles, and mammals in Europe. However, incorporating factors reflecting human pressures complementary to climate could be conducive to us understanding the drivers of functional diversity and richness patterns.

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Community characteristics of forest understory birds along an elevational gradient in the Horn of Africa: A multi-year baseline

The Condor ◽

10.1093/ornithapp/duab009 ◽

2021 ◽

Author(s):

Kyle D Kittelberger ◽

Montague H C Neate-Clegg ◽

Evan R Buechley ◽

Çağan Hakkı Şekercioğlu

Keyword(s):

Species Richness ◽

Species Turnover ◽

Survival Rates ◽

Elevational Gradient ◽

Forest Understory ◽

Bird Abundance ◽

Tropical Mountains ◽

Demographic Rates ◽

Understory Birds ◽

Over Time

Abstract Tropical mountains are global hotspots for birdlife. However, there is a dearth of baseline avifaunal data along elevational gradients, particularly in Africa, limiting our ability to observe and assess changes over time in tropical montane avian communities. In this study, we undertook a multi-year assessment of understory birds along a 1,750 m elevational gradient (1,430–3,186 m) in an Afrotropical moist evergreen montane forest within Ethiopia’s Bale Mountains. Analyzing 6 years of systematic bird-banding data from 5 sites, we describe the patterns of species richness, abundance, community composition, and demographic rates over space and time. We found bimodal patterns in observed and estimated species richness across the elevational gradient (peaking at 1,430 and 2,388 m), although no sites reached asymptotic species richness throughout the study. Species turnover was high across the gradient, though forested sites at mid-elevations resembled each other in species composition. We found significant variation across sites in bird abundance in some of the dietary and habitat guilds. However, we did not find any significant trends in species richness or guild abundances over time. For the majority of analyzed species, capture rates did not change over time and there were no changes in species’ mean elevations. Population growth rates, recruitment rates, and apparent survival rates averaged 1.02, 0.52, and 0.51 respectively, and there were no elevational patterns in demographic rates. This study establishes a multi-year baseline for Afrotropical birds along an elevational gradient in an under-studied international biodiversity hotspot. These data will be critical in assessing the long-term responses of tropical montane birdlife to climate change and habitat degradation.

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Changes of arthropod diversity across an altitudinal ecoregional zonation in Northwestern Argentina

PeerJ ◽

10.7717/peerj.4117 ◽

2017 ◽

Vol 5 ◽

pp. e4117 ◽

Cited By ~ 7

Author(s):

Andrea X. González-Reyes ◽

Jose A. Corronca ◽

Sandra M. Rodriguez-Artigas

Keyword(s):

Species Richness ◽

Polynomial Regression ◽

Species Turnover ◽

Predictor Variable ◽

Elevational Gradient ◽

Pitfall Trap ◽

Northwestern Argentina ◽

Higher Taxa ◽

Total Species Richness ◽

Wide Range

This study examined arthropod community patterns over an altitudinal ecoregional zonation that extended through three ecoregions (Yungas, Monte de Sierras y Bolsones, and Puna) and two ecotones (Yungas-Monte and Prepuna) of Northwestern Argentina (altitudinal range of 2,500 m), and evaluated the abiotic and biotic factors and the geographical distance that could influence them. Pitfall trap and suction samples were taken seasonally in 15 sampling sites (1,500–4,000 m a.s.l) during one year. In addition to climatic variables, several soil and vegetation variables were measured in the field. Values obtained for species richness between ecoregions and ecotones and by sampling sites were compared statistically and by interpolation–extrapolation analysis based on individuals at the same sample coverage level. Effects of predictor variables and the similarity of arthropods were shown using non-metric multidimensional scaling, and the resulting groups were evaluated using a multi-response permutation procedure. Polynomial regression was used to evaluate the relationship between altitude with total species richness and those of hyperdiverse/abundant higher taxa and the latter taxa with each predictor variable. The species richness pattern displayed a decrease in species diversity as the elevation increased at the bottom wet part (Yungas) of our altitudinal zonation until the Monte, and a unimodal pattern of diversity in the top dry part (Monte, Puna). Each ecoregion and ecotonal zone evidenced a particular species richness and assemblage of arthropods, but the latter ones displayed a high percentage of species shared with the adjacent ecoregions. The arthropod elevational pattern and the changes of the assemblages were explained by the environmental gradient (especially the climate) in addition to a geographic gradient (the distance of decay of similarity), demonstrating that the species turnover is important to explain the beta diversity along the elevational gradient. This suggests that patterns of diversity and distribution of arthropods are regulated by the dissimilarity of ecoregional environments that establish a wide range of geographic and environmental barriers, coupled with a limitation of species dispersal. Therefore, the arthropods of higher taxa respond differently to the altitudinal ecoregional zonation.

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Congruence between breeding and wintering biodiversity hotspots: A case study in farmlands of Western Poland

European Journal of Ecology ◽

10.2478/eje-2018-0014 ◽

2019 ◽

Vol 4 (2) ◽

pp. 75-83

Author(s):

Federico Morelli ◽

Zbigniew Kwieciński ◽

Piotr Indykiewicz ◽

Łukasz Jankowiak ◽

Paweł Szymański ◽

...

Keyword(s):

Species Richness ◽

Protected Areas ◽

Functional Diversity ◽

Conservation Status ◽

Bird Species ◽

Bird Community ◽

Bird Diversity ◽

Human Beings ◽

Complete Representation ◽

Evolutionary Distinctiveness

Abstract Farmland landscapes are recognized as important ecosystems, not only for their rich biodiversity but equally so for the human beings who live and work in these places. However, biodiversity varies among sites (spatial change) and among seasons (temporal change). In this work, we tested the hypothesis that bird diversity hotspots distribution for breeding is congruent with bird diversity hotspots for wintering season, focusing also the representation of protected areas for the conservation of local hotspots. We proposed a framework based on the use of species richness, functional diversity, and evolutionary distinctiveness to characterize avian communities. Although our findings show that the spatial distribution of local bird hotspots differed slightly between seasons, the protected areas’ representation was similar in both seasons. Protected areas covered 65% of the most important zones for breeding and 71% for the wintering season in the farmland studied. Functional diversity showed similar patterns as did bird species richness, but this measure can be most effective for highlighting differences on bird community composition. Evolutionary distinctiveness was less congruent with species richness and functional diversity, among seasons. Our findings suggest that inter-seasonal spatial congruence of local hotspots can be considered as suitable areas upon which to concentrate greater conservation efforts. However, even considering the relative congruence of avian diversity metrics at a local spatial scale, simultaneous analysis of protected areas while inter-seasonally considering hotspots, can provide a more complete representation of ecosystems for assessing the conservation status and designating priority areas.

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Context-dependency in biodiversity-multifunctionality relationships is driven by nitrogen availability and plant functional composition

10.1101/2020.08.17.254086 ◽

2020 ◽

Author(s):

Noémie A. Pichon ◽

Seraina L. Cappelli ◽

Santiago Soliveres ◽

Tosca Mannall ◽

Thu Zar Nwe ◽

...

Keyword(s):

Species Richness ◽

Plant Species ◽

Functional Diversity ◽

Experimental Studies ◽

Plant Species Richness ◽

Trophic Levels ◽

Context Dependency ◽

Composition Gradient ◽

Nitrogen Enrichment ◽

Functional Composition

SummaryThe ability of an ecosystem to deliver multiple functions at high levels (multifunctionality) typically increases with biodiversity but there is substantial variation in the strength and direction of biodiversity effects, suggesting context-dependency. However, the drivers of this context dependency have not been identified and understood in comparative meta-analyses or experimental studies. To determine how different factors modulate the effect of diversity on multifunctionality, we conducted a large grassland experiment with 216 communities, crossing a manipulation of plant species richness (1-20 species) with manipulations of resource availability (nitrogen enrichment), plant functional composition (gradient in mean specific leaf area [SLA] to manipulate abundances of fast vs. slow species), plant functional diversity (variance in SLA) and enemy abundance (fungal pathogen removal). We measured ten functions, above and belowground, related to productivity, nutrient cycling and energy transfer between trophic levels, and calculated multifunctionality. Plant species richness and functional diversity both increased multifunctionality, but their effects were context dependent. Species richness increased multifunctionality, but only when communities were assembled with fast growing (high SLA) species. This was because slow species were more redundant in their functional effects, whereas fast species tended to promote different functions. Functional diversity also increased multifunctionality but this effect was dampened by nitrogen enrichment, however, unfertilised, functionally diverse communities still delivered more functions than low diversity, fertilised communities. Our study suggests that a shift towards exploitative communities will not only alter ecosystem functioning but also the strength of biodiversity-functioning relationships, which highlights the potentially complex effects of global change on multifunctionality.

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Impact of urbanization on functional diversity in macromycete communities along an urban ecosystem in Southwest Mexico

PeerJ ◽

10.7717/peerj.12191 ◽

2021 ◽

Vol 9 ◽

pp. e12191

Author(s):

Marko Gómez-Hernández ◽

Emily Avendaño-Villegas ◽

María Toledo-Garibaldi ◽

Etelvina Gándara

Keyword(s):

Species Richness ◽

Functional Diversity ◽

Ecosystem Functioning ◽

Urban Ecosystem ◽

Niche Space ◽

Urbanization Gradient ◽

Urbanization Level ◽

Functional Value ◽

Functional Richness ◽

Available Resources

Macromycetes are a group of fungi characterized by the production of fruit bodies and are highly relevant in most terrestrial ecosystems as pathogens, mutualists, and organic matter decomposers. Habitat transformation can drastically alter macromycete communities and diminish the contribution of these organisms to ecosystem functioning; however, knowledge on the effect of urbanization on macrofungal communities is scarce. Diversity metrics based on functional traits of macromycete species have shown to be valuable tools to predict how species contribute to ecosystem functionality since traits determine the performance of species in ecosystems. The aim of this study was to assess patterns of species richness, functional diversity, and composition of macrofungi in an urban ecosystem in Southwest Mexico, and to identify microclimatic, environmental, and urban factors related to these patterns in order to infer the effect of urbanization on macromycete communities. We selected four oak forests along an urbanization gradient and established a permanent sampling area of 0.1 ha at each site. Macromycete sampling was carried out every week from June to October 2017. The indices used to measure functional diversity were functional richness (FRic), functional divergence (FDig), and functional evenness (FEve). The metric used to assess variation of macrofungal ecological function along the study area was the functional value. We recorded a total of 134 macromycete species and 223 individuals. Our results indicated a decline of species richness with increased urbanization level related mainly to microclimatic variables, and a high turnover of species composition among study sites, which appears to be related to microclimatic and urbanization variables. FRic decreased with urbanization level, indicating that some of the available resources in the niche space within the most urbanized sites are not being utilized. FDig increased with urbanization, which suggests a high degree of niche differentiation among macromycete species within communities in urbanized areas. FEve did not show notable differences along the urbanization gradient, indicating few variations in the distribution of abundances within the occupied sections of the niche space. Similarly, the functional value was markedly higher in the less urbanized site, suggesting greater performance of functional guilds in that area. Our findings suggest that urbanization has led to a loss of macromycete species and a decrease in functional diversity, causing some sections of the niche space to be hardly occupied and available resources to be under-utilized, which could, to a certain extent, affect ecosystem functioning and stability.

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