| 1. |
- Alves-Martins, Fernanda, et al.
(författare)
-
Drivers of regional and local diversity of Amazonian stream Odonata
- 2019
-
Ingår i: Insect Conservation and Diversity. - : Wiley-Blackwell. - 1752-458X .- 1752-4598. ; 12:3, s. 251-261
-
Tidskriftsartikel (refereegranskat)abstract
- Large Amazonian rivers may act as dispersal barriers for animals with low dispersal abilities, limiting their distribution to certain interfluves. Consequently, the distribution of these taxa would be less affected by macroclimatic gradients. Conversely, high-dispersal taxa would be less constrained by large rivers and may track suitable climates. We evaluate whether Zygoptera and Anisoptera, two Odonata suborders with different dispersal abilities, show differences in distribution patterns across Amazonian interfluves. We further assess the relative importance of macroclimatic and habitat factors in their community assembly. We used network modularity analyses to identify biogeographic species pools and spatial buffers to define metacommunity species pools. Then, we used structural equationmodels to estimate the relative importance of multi-scale factors on species richness patterns. Zygoptera communities are more similar in species composition within than between interfluves, suggesting that large Amazonian rivers indeed limit the distribution of Zygoptera species. Conversely, the distribution of Anisoptera extends across Amazonian interfluves. Seasonality has a strong positive effect on Zygoptera and Anisoptera richness across scales. In addition, habitat integrity is negatively correlated with the regional species richness and abundance of Anisoptera and positively correlated with Zygoptera local richness. The contrasting effects of habitat integrity on Anisoptera and Zygoptera suggest that the former is favored in open habitats, whereas the latter is so in forests. Despite these differences, both suborders appear to follow similar community assembly mechanisms in Amazonia, with a strong climatic control across scales and an effect of habitat filters on local communities.
|
|
| 2. |
- Calatayud, Joaquín, et al.
(författare)
-
Positive associations among rare species and their persistence in ecological assemblages
- 2020
-
Ingår i: Nature Ecology & Evolution. - : Nature Publishing Group. - 2397-334X. ; 4:1, s. 40-45
-
Tidskriftsartikel (refereegranskat)abstract
- According to the competitive exclusion principle, species with low competitive abilities should be excluded by more efficient competitors; yet, they generally remain as rare species. Here, we describe the positive and negative spatial association networks of 326 disparate assemblages, showing a general organization pattern that simultaneously supports the primacy of competition and the persistence of rare species. Abundant species monopolize negative associations in about 90% of the assemblages. On the other hand, rare species are mostly involved in positive associations, forming small network modules. Simulations suggest that positive interactions among rare species and microhabitat preferences are the most probable mechanisms underpinning this pattern and rare species persistence. The consistent results across taxa and geography suggest a general explanation for the maintenance of biodiversity in competitive environments. Analysing spatial association networks among >300 terrestrial and aquatic assemblages, the authors find that the majority of negative associations involve abundant species. In contrast, rare species form mostly positive associations, potentially explaining their persistence in natural communities.
|
|
| 3. |
- Smith, Brenda D., et al.
(författare)
-
Odonata assemblages in human-modified landscapes
- 2023. - 2
-
Ingår i: Dragonflies and Damselflies. - Oxford : Oxford University Press. - 9780192898623 - 9780191924903 ; , s. 247-260
-
Bokkapitel (refereegranskat)abstract
- Human activities such as logging, agriculture, and urbanization can drastically change and limit Odonata species distributions in aquatic and terrestrial environments. These modifications may culminate in extirpations of rare and resident species and homogenization of community composition across space. This chapter reviews how human land use is (re)shaping odonate assemblages and focuses on the impacts from logging, agriculture, and urbanization. Deeper appreciation and analysis of regulatory mechanisms (e.g. vulnerability traits, species interactions, phylogenetic niche conservatism) and background “noise” (e.g. natural heterogeneity, climate change, historical context) will be important in understanding and predicting odonate community responses to ongoing and future landscape alteration.
|
|
