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Functional and phylogenetic relatedness in temporary wetland invertebrates: current macroecological patterns and implications for future climatic change scenarios.

Ruhí A, Boix D, Gascón S, Sala J, Batzer DP - PLoS ONE (2013)

Bottom Line: Functional overlap of invertebrates increased from mild (i.e., Temperate) to harsher climates (i.e., Arid and Cold), and phylogenetic clustering (using taxonomy as a surrogate) was highest in Arid and lowest in Temperate wetlands.We show that, (i) as has been described in streams, higher relatedness than would be expected by chance is generally observed in seasonal wetland invertebrate communities; and (ii) this relatedness is not constant but climate-dependent, with the climate under which a given seasonal wetland is located determining the functional overlap and the phylogenetic clustering of the community.Finally, using a space-for-time substitution approach we suggest our results may anticipate how the invertebrate biodiversity embedded in these vulnerable and often overlooked ecosystems will be affected by long-term climate change.

View Article: PubMed Central - PubMed

Affiliation: Institute of Aquatic Ecology, University of Girona, Girona, Catalonia, Spain ; Catalan Institute for Water Research, Girona, Catalonia, Spain.

ABSTRACT
In freshwater ecosystems, species compositions are known to be determined hierarchically by large to small‑scale environmental factors, based on the biological traits of the organisms. However, in ephemeral habitats this heuristic framework remains largely untested. Although temporary wetland faunas are constrained by a local filter (i.e., desiccation), we propose its magnitude may still depend on large-scale climate characteristics. If this is true, climate should be related to the degree of functional and taxonomic relatedness of invertebrate communities inhabiting seasonal wetlands. We tested this hypothesis in two ways. First, based on 52 biological traits for invertebrates, we conducted a case study to explore functional trends among temperate seasonal wetlands differing in the harshness (i.e., dryness) of their dry season. After finding evidence of trait filtering, we addressed whether it could be generalized across a broader climatic scale. To this end, a meta-analysis (225 seasonal wetlands spread across broad climatic categories: Arid, Temperate, and Cold) allowed us to identify whether an equivalent climate-dependent pattern of trait richness was consistent between the Nearctic and the Western Palearctic. Functional overlap of invertebrates increased from mild (i.e., Temperate) to harsher climates (i.e., Arid and Cold), and phylogenetic clustering (using taxonomy as a surrogate) was highest in Arid and lowest in Temperate wetlands. We show that, (i) as has been described in streams, higher relatedness than would be expected by chance is generally observed in seasonal wetland invertebrate communities; and (ii) this relatedness is not constant but climate-dependent, with the climate under which a given seasonal wetland is located determining the functional overlap and the phylogenetic clustering of the community. Finally, using a space-for-time substitution approach we suggest our results may anticipate how the invertebrate biodiversity embedded in these vulnerable and often overlooked ecosystems will be affected by long-term climate change.

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Patterns of taxonomic clustering among climates within each ecozone (NE = Nearctic, WP = Western Palearctic).(A) Mean ± SE values of Delta+, informing about taxonomic relatedness (relatively higher Delta+ values imply assemblages with taxonomically closer members); (B) % of sites presenting lower-than-expected taxonomic relatedness (HA1, overdispersion), expected taxonomic relatedness (H0, random clustering) and higher-than-expected taxonomic relatedness (HA2, clustering).
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pone-0081739-g007: Patterns of taxonomic clustering among climates within each ecozone (NE = Nearctic, WP = Western Palearctic).(A) Mean ± SE values of Delta+, informing about taxonomic relatedness (relatively higher Delta+ values imply assemblages with taxonomically closer members); (B) % of sites presenting lower-than-expected taxonomic relatedness (HA1, overdispersion), expected taxonomic relatedness (H0, random clustering) and higher-than-expected taxonomic relatedness (HA2, clustering).

Mentions: Finally, taxonomic relatedness patterns differed among climates within each ecozone (Wald Chi-Square = 46.449, df = 6, p < 0.001), but not across ecozones overall (Wald Chi-Square = 0.090, df = 1, p > 0.5). The highest values of Average Taxonomic Distinctness (Delta+) were found in Mild Summer Temperate wetlands and decreased towards Arid and Cold climates in both ecozones, as predicted (Figure 7). Only in the Mild Summer Temperate climate did some wetlands exhibit a lower-than-expected taxonomic relatedness (HA1, overdispersion), with 1 site in the NE (5 % of sites under this climate) and 4 sites in the WP (25 %). On the other hand, only a few cases of higher-than-expected taxonomic relatedness (HA2, clustering) were found in Mild Summer Temperate wetlands, with 2 sites in the NE (9 % of sites under this climate) and 1 site in the WP (6 %). As expected, the number of taxonomically-clustered sites tended to increase when moving towards Arid and Cold climates, achieving maximum values in the Arid climate in both ecozones, with 5 sites in the NE (33 % of wetlands under this climate) and 10 sites in the WP (50 %) (Figure 7).


Functional and phylogenetic relatedness in temporary wetland invertebrates: current macroecological patterns and implications for future climatic change scenarios.

Ruhí A, Boix D, Gascón S, Sala J, Batzer DP - PLoS ONE (2013)

Patterns of taxonomic clustering among climates within each ecozone (NE = Nearctic, WP = Western Palearctic).(A) Mean ± SE values of Delta+, informing about taxonomic relatedness (relatively higher Delta+ values imply assemblages with taxonomically closer members); (B) % of sites presenting lower-than-expected taxonomic relatedness (HA1, overdispersion), expected taxonomic relatedness (H0, random clustering) and higher-than-expected taxonomic relatedness (HA2, clustering).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3842952&req=5

pone-0081739-g007: Patterns of taxonomic clustering among climates within each ecozone (NE = Nearctic, WP = Western Palearctic).(A) Mean ± SE values of Delta+, informing about taxonomic relatedness (relatively higher Delta+ values imply assemblages with taxonomically closer members); (B) % of sites presenting lower-than-expected taxonomic relatedness (HA1, overdispersion), expected taxonomic relatedness (H0, random clustering) and higher-than-expected taxonomic relatedness (HA2, clustering).
Mentions: Finally, taxonomic relatedness patterns differed among climates within each ecozone (Wald Chi-Square = 46.449, df = 6, p < 0.001), but not across ecozones overall (Wald Chi-Square = 0.090, df = 1, p > 0.5). The highest values of Average Taxonomic Distinctness (Delta+) were found in Mild Summer Temperate wetlands and decreased towards Arid and Cold climates in both ecozones, as predicted (Figure 7). Only in the Mild Summer Temperate climate did some wetlands exhibit a lower-than-expected taxonomic relatedness (HA1, overdispersion), with 1 site in the NE (5 % of sites under this climate) and 4 sites in the WP (25 %). On the other hand, only a few cases of higher-than-expected taxonomic relatedness (HA2, clustering) were found in Mild Summer Temperate wetlands, with 2 sites in the NE (9 % of sites under this climate) and 1 site in the WP (6 %). As expected, the number of taxonomically-clustered sites tended to increase when moving towards Arid and Cold climates, achieving maximum values in the Arid climate in both ecozones, with 5 sites in the NE (33 % of wetlands under this climate) and 10 sites in the WP (50 %) (Figure 7).

Bottom Line: Functional overlap of invertebrates increased from mild (i.e., Temperate) to harsher climates (i.e., Arid and Cold), and phylogenetic clustering (using taxonomy as a surrogate) was highest in Arid and lowest in Temperate wetlands.We show that, (i) as has been described in streams, higher relatedness than would be expected by chance is generally observed in seasonal wetland invertebrate communities; and (ii) this relatedness is not constant but climate-dependent, with the climate under which a given seasonal wetland is located determining the functional overlap and the phylogenetic clustering of the community.Finally, using a space-for-time substitution approach we suggest our results may anticipate how the invertebrate biodiversity embedded in these vulnerable and often overlooked ecosystems will be affected by long-term climate change.

View Article: PubMed Central - PubMed

Affiliation: Institute of Aquatic Ecology, University of Girona, Girona, Catalonia, Spain ; Catalan Institute for Water Research, Girona, Catalonia, Spain.

ABSTRACT
In freshwater ecosystems, species compositions are known to be determined hierarchically by large to small‑scale environmental factors, based on the biological traits of the organisms. However, in ephemeral habitats this heuristic framework remains largely untested. Although temporary wetland faunas are constrained by a local filter (i.e., desiccation), we propose its magnitude may still depend on large-scale climate characteristics. If this is true, climate should be related to the degree of functional and taxonomic relatedness of invertebrate communities inhabiting seasonal wetlands. We tested this hypothesis in two ways. First, based on 52 biological traits for invertebrates, we conducted a case study to explore functional trends among temperate seasonal wetlands differing in the harshness (i.e., dryness) of their dry season. After finding evidence of trait filtering, we addressed whether it could be generalized across a broader climatic scale. To this end, a meta-analysis (225 seasonal wetlands spread across broad climatic categories: Arid, Temperate, and Cold) allowed us to identify whether an equivalent climate-dependent pattern of trait richness was consistent between the Nearctic and the Western Palearctic. Functional overlap of invertebrates increased from mild (i.e., Temperate) to harsher climates (i.e., Arid and Cold), and phylogenetic clustering (using taxonomy as a surrogate) was highest in Arid and lowest in Temperate wetlands. We show that, (i) as has been described in streams, higher relatedness than would be expected by chance is generally observed in seasonal wetland invertebrate communities; and (ii) this relatedness is not constant but climate-dependent, with the climate under which a given seasonal wetland is located determining the functional overlap and the phylogenetic clustering of the community. Finally, using a space-for-time substitution approach we suggest our results may anticipate how the invertebrate biodiversity embedded in these vulnerable and often overlooked ecosystems will be affected by long-term climate change.

Show MeSH
Related in: MedlinePlus