Species packing and the latitudinal gradient in local beta-diversity

AbstractThe latitudinal gradient of declining species richness at higher latitudes is among the most fundamental patterns in ecology. However, whether changes in species composition across space (beta-diversity) contribute to this global gradient of species richness remains debated. Previous studies that failed to resolve the issue suffered from a well-known tendency for small samples in high gamma-diversity areas to inflate measures of beta-diversity. We provide here a rigorous test, comparing species-packing and local heterogeneity across a latitudinal gradient in tree species richness in Asia, using beta-diversity metrics that correct the gamma-diversity and sampling bias. Our data include 21 large forest plots across a wide environmental gradient in East Asia. We demonstrate that local beta-diversity increases with topographic heterogeneity, but after accounting for this and correcting the gamma-diversity bias, tropical forests still have higher beta-diversity than temperate, contributing to the latitudinal gradient of species richness. This supports the hypothesis of tighter species packing and larger niche space in tropical forests while demonstrating the importance of local processes in controlling beta-diversity.

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Species packing and the latitudinal gradient in beta-diversity

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.3045 ◽

2021 ◽

Vol 288 (1948) ◽

Author(s):

Ke Cao ◽

Richard Condit ◽

Xiangcheng Mi ◽

Lei Chen ◽

Haibao Ren ◽

...

Keyword(s):

Species Richness ◽

Tropical Forests ◽

Beta Diversity ◽

Environmental Gradient ◽

Latitudinal Gradient ◽

Small Samples ◽

Gamma Diversity ◽

Species Packing ◽

High Gamma ◽

Species Richness Gradient

The decline in species richness at higher latitudes is among the most fundamental patterns in ecology. Whether changes in species composition across space (beta-diversity) contribute to this gradient of overall species richness (gamma-diversity) remains hotly debated. Previous studies that failed to resolve the issue suffered from a well-known tendency for small samples in areas with high gamma-diversity to have inflated measures of beta-diversity. Here, we provide a novel analytical test, using beta-diversity metrics that correct the gamma-diversity and sampling biases, to compare beta-diversity and species packing across a latitudinal gradient in tree species richness of 21 large forest plots along a large environmental gradient in East Asia. We demonstrate that after accounting for topography and correcting the gamma-diversity bias, tropical forests still have higher beta-diversity than temperate analogues. This suggests that beta-diversity contributes to the latitudinal species richness gradient as a component of gamma-diversity. Moreover, both niche specialization and niche marginality (a measure of niche spacing along an environmental gradient) also increase towards the equator, after controlling for the effect of topographical heterogeneity. This supports the joint importance of tighter species packing and larger niche space in tropical forests while also demonstrating the importance of local processes in controlling beta-diversity.

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High Gamma Diversity and Low Beta Diversity of Non-Biting Midges (Diptera: Chironomidae) in Streams of the Gorkhi Terelj National Park, Outer Mongolia

Proceedings of the Academy of Natural Sciences of Philadelphia ◽

10.1635/053.159.0109 ◽

2010 ◽

Vol 159 (1) ◽

pp. 169-184 ◽

Cited By ~ 2

Author(s):

Barbara L. Hayford

Keyword(s):

Beta Diversity ◽

National Park ◽

Gamma Diversity ◽

Biting Midges ◽

High Gamma

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Faculty Opinions recommendation of Big-sized trees overrule remaining trees' attributes and species richness as determinants of aboveground biomass in tropical forests.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.735819621.793578053 ◽

2020 ◽

Author(s):

Bernhard Schmid

Keyword(s):

Species Richness ◽

Tropical Forests ◽

Aboveground Biomass

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Partitioning tree diversity patterns to prioritize conservation investments

Environmental Conservation ◽

10.1017/s0376892921000060 ◽

2021 ◽

pp. 1-9

Author(s):

Patrick F McKenzie ◽

Gwenllian D Iacona ◽

Eric R Larson ◽

Paul R Armsworth

Keyword(s):

Protected Areas ◽

Predictive Models ◽

Tree Species ◽

Beta Diversity ◽

Distribution Data ◽

Gamma Diversity ◽

Conservation Practice ◽

Alpha And Beta Diversity ◽

Community Turnover ◽

Data Limitations

Summary The available tools and approaches to inform conservation decisions commonly assume detailed distribution data. We examine how well-established ecological concepts about patterns in local richness and community turnover can help overcome data limitations when planning future protected areas. To inform our analyses, we surveyed tree species in protected areas in the southern Appalachian Mountains in the eastern USA. We used the survey data to construct predictive models for alpha and beta diversity based on readily observed biophysical variables and combined them to create a heuristic that could predict among-site richness in trees (gamma diversity). The predictive models suggest that site elevation and latitude in this montane system explain much of the variation in alpha and beta diversity in tree species. We tested how well resulting protected areas would represent species if a conservation planner lacking detailed species inventories for candidate sites were to rely only on our alpha, beta and gamma diversity predictions. Our approach selected sites that, when aggregated, covered a large proportion of the overall species pool. The combined gamma diversity models performed even better when we also accounted for the cost of protecting sites. Our results demonstrate that classic community biogeography concepts remain highly relevant to conservation practice today.

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Floristic composition of the Montane Forest in the Almadina-Barro Preto axis, Southern Bahia, Brazil

Biota Neotropica ◽

10.1590/s1676-06033878 ◽

2014 ◽

Vol 14 (1) ◽

Cited By ~ 9

Author(s):

Macielle Macedo Coelho ◽

André Márcio Amorim

Keyword(s):

Species Richness ◽

Tropical Forests ◽

Atlantic Forest ◽

Floristic Composition ◽

Woody Species ◽

Life Forms ◽

Montane Forest ◽

Forest Remnants ◽

Southern Bahia ◽

Arboreal Habit

The aim of this study is to survey the angiosperms of two montane forest remnants in the southern Bahia, Brazil: Corcovado (SCO) and Pedra Lascada (SPL). Both fragments are located in the municipality of Almadina and Barro Preto, respectively, and are 18 km distant from each other. We sampled 899 species of angiosperms distributed in 437 genera and 116 families. The SCO was the richest area with 678 species, distributed in 367 genera and 100 families. SPL showed 466 species in 269 genera and 88 families. The percentage of species identified was 85.8% and of this total, 37.7% are endemic to the Atlantic Forest, 11.2% are endemic to southern Bahia and northern Espírito Santo and 7% are disjunct between the Atlantic Forest and Amazon. The remaining percentages (44.3%) were of species widely distributed. The richest families in the two areas were Orchidaceae (10%), Rubiaceae (7%), Bromeliaceae (5.5%), Melastomataceae (4.2%) and Poaceae (4%). The richest genera were Psychotria (2%),Piper (1.8%), Ocotea (1.6%),Vriesea (1.5%) and Peperomia (1.4%). More than half of the recorded species showed non-arboreal habit, regarding life forms documented. That comes against the assertion that many authors in the tropical forests, where species richness in angiosperms is expected for non-woody species, especially in montane forests. Twelve species have been identified as new, but seven others already described from collections previously obtained in these two areas. Orchidaceae, Rubiaceae, Poaceae and Bromeliaceae showed significant richness in this study these families are commonly reported as the richest in other inventories in the Atlantic Forest in southern Bahia reinforcing their importance to the regional flora. The high levels of richness, endemism, and the growing numbers of new taxonomic discoveries from the SPL and SCO sites indicate the biological importance of these two forest remnants. The implementation of parks or other protected environmental reserves would be essential to the conservation of its species.

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Aquatic macrophyte community varies in urban reservoirs with different degrees of eutrophication

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x2014000200004 ◽

2014 ◽

Vol 26 (2) ◽

pp. 129-142 ◽

Cited By ~ 3

Author(s):

Suelen Cristina Alves da Silva ◽

Armando Carlos Cervi ◽

Cleusa Bona ◽

André Andrian Padial

Keyword(s):

Species Richness ◽

Temporal Variation ◽

Indicator Species ◽

Beta Diversity ◽

Aquatic Macrophytes ◽

Aquatic Macrophyte ◽

Wiener Index ◽

Spatial And Temporal Variation ◽

Macrophyte Community ◽

Aquatic Macrophyte Community

AIM: Investigate spatial and temporal variation in the aquatic macrophyte community in four urban reservoirs located in Curitiba metropolitan region, Brazil. We tested the hypothesis that aquatic macrophyte community differ among reservoirs with different degrees of eutrophication. METHODS: The reservoirs selected ranged from oligotrophic/mesotrophic to eutrophic. Sampling occurred in October 2011, January 2012 and June 2012. Twelve aquatic macrophytes stands were sampled at each reservoir. Species were identified and the relative abundance of aquatic macrophytes was estimated. Differences among reservoirs and over sampling periods were analyzed: i) through two‑way ANOVAs considering the stand extent (m) and the stand biodiversity - species richness, evenness, Shannon-Wiener index and beta diversity (species variation along the aquatic macrophyte stand); and ii) through PERMANOVA considering species composition. Indicator species that were characteristic for each reservoir were also identified. RESULTS: The aquatic macrophyte stand extent varied among reservoirs and over sampling periods. Species richness showed only temporal variation. On the other hand, evenness and Shannon-Wiener index varied only among reservoirs. The beta diversity of macrophyte stands did not vary among reservoirs or over time, meaning that species variability among aquatic macrophyte stands was independent of the stand extent and reservoir eutrophication. Community composition depended on the reservoir and sampling period. CONCLUSIONS: Our results support our initial expectation that reservoirs of different degrees of eutrophication have different aquatic macrophyte communities. As a consequence, each reservoir had particular indicator species. Therefore, monitoring and management efforts must be offered for each reservoir individually.

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