Community structure of dung beetles in Amazonian savannas: role of fire disturbance, vegetation and landscape structure

Pollen records can provide information on past landscape structure, but the interpretation is not straightforward, as plants differ in their pollen production and -dispersal properties. Especially open areas are generally under-represented in pollen diagrams. However, in recent years new models have been developed, which take these factors into account and allow us to correct for them, for example by simulating pollen sedimentation in hypothetical landscapes.In this study, simulated landscapes were created based on landscapes without and with different levels of grazing impact. Pollen deposition in these landscapes was simulated using a model of pollen representation, dispersal and deposition, and the resulting pollen spectra were statistically compared to existing pollen records from Denmark from the Atlantic period (ca. 6800-3900 BC).The analysis showed that many of the pollen diagrams from eastern Denmark were most similar to the scenarios based on a rather closed forest landscape with some wetland areas, whereas for many diagrams in western Denmark, the pollen diagrams are compatible with a landscape which was more open. This openness was possibly due to a larger impact from grazing animals, which had a higher diversity in western than in eastern Denmark, but other factors, especially soil types and the frequency of fire disturbance, may also have played a role, as these also differ between eastern and western Denmark. Certain aspects of the pollen signal, for example the large proportion of Hazel, were not well explained by any scenarios, and require further study.

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Wood Pastures: A Transitional Habitat between Forests and Pastures for Dung Beetle Assemblages

Forests ◽

10.3390/f12010025 ◽

2020 ◽

Vol 12 (1) ◽

pp. 25

Author(s):

László Somay ◽

Viktor Szigeti ◽

Gergely Boros ◽

Réka Ádám ◽

András Báldi

Keyword(s):

Functional Group ◽

Animal Health ◽

Habitat Type ◽

Dung Beetle ◽

Dung Beetles ◽

Livestock Grazing ◽

Pitfall Traps ◽

Assemblage Composition ◽

Beetle Assemblages

Wood pastures are home to a variety of species, including the dung beetle. Dung beetles are an important functional group in decomposition. Specifically, in terms of livestock manure, they not only contribute to nutrient cycling but are key players in supporting human and animal health. Dung beetles, however, are declining in population, and urgent recommendations are needed to reverse this trend. Recommendations need to be based on solid evidence and specific habitats. Herein, we aimed to investigate the role of an intermediate habitat type between forests and pastures. Wood pastures are key areas for dung beetle conservation. For this reason, we compared dung beetle assemblages among forests, wood pastures, and grasslands. We complemented this with studies on the effects of dung type and season at three Hungarian locations. Pitfall traps baited with cattle, sheep, or horse dung were used in forests, wood pastures, and pasture habitats in spring, summer, and autumn. Dung beetle assemblages of wood pastures showed transient characteristics between forests and pastures regarding their abundance, species richness, Shannon diversity, assemblage composition, and indicator species. We identified a strong effect of season and a weak of dung type. Assemblage composition proved to be the most sensitive measure of differences among habitats. The conservation of dung beetles, and the decomposition services they provide, need continuous livestock grazing to provide fresh dung, as well as the maintenance of wood pastures where dung beetle assemblages typical of forests and pastures can both survive.

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Effects of human‐dominated landscape on the community structure of silphid and dung beetles collected by carrion pitfall traps

Entomological Science ◽

10.1111/ens.12466 ◽

2021 ◽

Author(s):

Kyosuke Shizukuda ◽

Masayuki U. Saito

Keyword(s):

Community Structure ◽

Dung Beetles ◽

Pitfall Traps

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An inter-dependence of flood and drought: disentangling amphibian beta diversity in seasonal floodplains

Marine and Freshwater Research ◽

10.1071/mf16391 ◽

2017 ◽

Vol 68 (11) ◽

pp. 2115 ◽

Cited By ~ 2

Author(s):

Leonardo F. B. Moreira ◽

Tainá F. Dorado-Rodrigues ◽

Vanda L. Ferreira ◽

Christine Strüssmann

Keyword(s):

Community Structure ◽

Environmental Factors ◽

Quantitative Data ◽

Explanatory Variable ◽

Biotic Interactions ◽

Ecological Role ◽

Β Diversity ◽

Amphibian Community ◽

Dry Seasons

Species composition in floodplains is often affected by different structuring factors. Although floods play a key ecological role, habitat selection in the dry periods may blur patterns of biodiversity distribution. Here, we employed a partitioning framework to investigate the contribution of turnover and nestedness to β-diversity patterns in non-arboreal amphibians from southern Pantanal ecoregion. We investigated whether components of β-diversity change by spatial and environmental factors. We sampled grasslands and dense arboreal savannas distributed in 12 sampling sites across rainy and dry seasons, and analysed species dissimilarities using quantitative data. In the savannas, both turnover and nestedness contributed similarly to β diversity. However, we found that β diversity is driven essentially by turnover, in the grasslands. In the rainy season, balanced variation in abundance was more related to altitude and factors that induce spatial patterns, whereas dissimilarities were not related to any explanatory variable during dry season. In the Pantanal ecoregion, amphibian assemblages are influenced by a variety of seasonal constraints on terrestrial movements and biotic interactions. Our findings highlighted the role of guild-specific patterns and indicated that mass effects are important mechanisms creating amphibian community structure in the Pantanal.

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The role of fire disturbance for global vegetation dynamics: coupling fire into a Dynamic Global Vegetation Model

Global Ecology and Biogeography ◽

10.1046/j.1466-822x.2001.00175.x ◽

2001 ◽

Vol 10 (6) ◽

pp. 661-677 ◽

Cited By ~ 417

Author(s):

Kirsten Thonicke ◽

Sergey Venevsky ◽

Stephen Sitch ◽

Wolfgang Cramer

Keyword(s):

Vegetation Dynamics ◽

Fire Disturbance ◽

Vegetation Model ◽

Dynamic Global Vegetation Model ◽

Global Vegetation

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Stochastic Assembly Leads to Alternative Communities with Distinct Functions in a Bioreactor Microbial Community

mBio ◽

10.1128/mbio.00584-12 ◽

2013 ◽

Vol 4 (2) ◽

Cited By ~ 128

Author(s):

Jizhong Zhou ◽

Wenzong Liu ◽

Ye Deng ◽

Yi-Huei Jiang ◽

Kai Xue ◽

...

Keyword(s):

Community Structure ◽

Microbial Community ◽

Microbial Diversity ◽

Microbial Community Structure ◽

Community Assembly ◽

Ecosystem Functioning ◽

Dominant Role ◽

Microbial Biodiversity ◽

Stochastic Assembly

ABSTRACTThe processes and mechanisms of community assembly and its relationships to community functioning are central issues in ecology. Both deterministic and stochastic factors play important roles in shaping community composition and structure, but the connection between community assembly and ecosystem functioning remains elusive, especially in microbial communities. Here, we used microbial electrolysis cell reactors as a model system to examine the roles of stochastic assembly in determining microbial community structure and functions. Under identical environmental conditions with the same source community, ecological drift (i.e., initial stochastic colonization) and subsequent biotic interactions created dramatically different communities with little overlap among 14 identical reactors, indicating that stochastic assembly played dominant roles in determining microbial community structure. Neutral community modeling analysis revealed that deterministic factors also played significant roles in shaping microbial community structure in these reactors. Most importantly, the newly formed communities differed substantially in community functions (e.g., H2production), which showed strong linkages to community structure. This study is the first to demonstrate that stochastic assembly plays a dominant role in determining not only community structure but also ecosystem functions. Elucidating the links among community assembly, biodiversity, and ecosystem functioning is critical to understanding ecosystem functioning, biodiversity preservation, and ecosystem management.IMPORTANCEMicroorganisms are the most diverse group of life known on earth. Although it is well documented that microbial natural biodiversity is extremely high, it is not clear why such high diversity is generated and maintained. Numerous studies have established the roles of niche-based deterministic factors (e.g., pH, temperature, and salt) in shaping microbial biodiversity, the importance of stochastic processes in generating microbial biodiversity is rarely appreciated. Moreover, while microorganisms mediate many ecosystem processes, the relationship between microbial diversity and ecosystem functioning remains largely elusive. Using a well-controlled laboratory system, this study provides empirical support for the dominant role of stochastic assembly in creating variations of microbial diversity and the first explicit evidence for the critical role of community assembly in influencing ecosystem functioning. The results presented in this study represent important contributions to the understanding of the mechanisms, especially stochastic processes, involved in shaping microbial biodiversity.

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