Oligochaetes in the southern basin of the Venetian Lagoon: community composition, species abundance and biomass

AbstractOne of the main goals of community ecology is to understand the influence of the abiotic environment on the abundance and distribution of species. It has been hypothesized that dry forests are harsher environments than wet forests, which leads to the prediction that environmental filtering should be a more important determinant of patterns of species abundance and composition than in wet forest, where biotic interactions or random assembly should be more important. We attempt to understand the influence of rainfall on the abundance and distribution of bird species along a steep precipitation gradient in an inter-Andean valley in Colombia. We gathered data on species distributions, abundance, morphological traits and phylogenetic relationships to determine the influence of rainfall on the taxonomic, functional and phylogenetic turnover of species along the Magdalena Valley. We demonstrate that there is a strong turnover of community composition at the limit of the dry forest. The taxonomic turnover is steeper than the phylogenetic turnover, suggesting that replacement of closely related species accounts for a disproportionate number of changes along the gradient. We found evidence for environmental filtering in dry forest as species tend to be more tolerant of higher temperature ranges, stronger rainfall seasonality and lower minimum rainfall. On the other hand, wet forest species tend to compete actively for nest space but not for the resources associated with the axes we measured. Our results suggest that rainfall is a strong determinant of community composition when comparing localities above and below the 2400 mm rainfall isocline.

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A ~6000 yr diatom record of mid- to late Holocene fluctuations in the level of Lago Wiñaymarca, Lake Titicaca (Peru/Bolivia)

Quaternary Research ◽

10.1017/qua.2017.49 ◽

2017 ◽

Vol 88 (2) ◽

pp. 179-192 ◽

Cited By ~ 8

Author(s):

D. Marie Weide ◽

Sherilyn C. Fritz ◽

Christine A. Hastorf ◽

Maria C. Bruno ◽

Paul A. Baker ◽

...

Keyword(s):

Shallow Lake ◽

Lake Level ◽

Late Holocene ◽

Species Abundance ◽

Freshwater Species ◽

Diatom Species ◽

Deep Lake ◽

Lake Titicaca ◽

Southern Basin ◽

Species Abundance Data

AbstractA multidecadal-scale lake-level reconstruction for Lago Wiñaymarca, the southern basin of Lake Titicaca, has been generated from diatom species abundance data. These data suggest that ~6500 cal yr BP Lago Wiñaymarca was dry, as indicated by a sediment unconformity. At ~4400 cal yr BP, the basin began to fill, as indicated by the dominance of shallow epiphytic species. It remained somewhat saline with extensive wetlands and abundant aquatic plants until ~3800 cal yr BP, when epiphytic species were replaced by planktic saline-indifferent species, suggesting a saline shallow lake. Wiñaymarca remained a relatively shallow lake that fluctuated on a multidecadal scale until ~1250 cal yr BP, when freshwater planktic species increased, suggesting a rise in lake level with a concomitant decrease in salinity. The lake became gradually fresher, dominated by deep, freshwater species from ~850 cal yr BP. By ~80 cal yr BP, saline-tolerant species were rare, and the lake was dominated by freshwater planktic diatoms, resembling the fresh and deep lake of today. These results reveal a more dynamic and chronologically specific record of lake-level fluctuations and associated ecological conditions that provide important new data for paleoclimatologists and archaeologists, to better understand human-environmental dynamics during the mid- to late Holocene.

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Strong upwelling conditions drive differences in species abundance and community composition along the Atlantic coasts of Morocco and Western Sahara

Marine Biodiversity ◽

10.1007/s12526-019-01032-z ◽

2020 ◽

Vol 50 (2) ◽

Author(s):

Carla R. Lourenço ◽

Katy R. Nicastro ◽

Christopher D. McQuaid ◽

Lilian A. Krug ◽

Gerardo I. Zardi

Keyword(s):

Community Composition ◽

Species Abundance ◽

Western Sahara

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Changes in composition and abundance of functional groups of arctic fungi in response to long-term summer warming

Biology Letters ◽

10.1098/rsbl.2016.0503 ◽

2016 ◽

Vol 12 (11) ◽

pp. 20160503 ◽

Cited By ~ 19

Author(s):

József Geml ◽

Tatiana A. Semenova ◽

Luis N. Morgado ◽

Jeffrey M. Welker

Keyword(s):

Nutrient Cycling ◽

Functional Groups ◽

Community Composition ◽

Species Abundance ◽

Species Level ◽

Fungal Communities ◽

Summer Warming ◽

Species Specific

We characterized fungal communities in dry and moist tundra and investigated the effect of long-term experimental summer warming on three aspects of functional groups of arctic fungi: richness, community composition and species abundance. Warming had profound effects on community composition, abundance, and, to a lesser extent, on richness of fungal functional groups. In addition, our data show that even within functional groups, the direction and extent of response to warming tend to be species-specific and we recommend that studies on fungal communities and their roles in nutrient cycling take into account species-level responses.

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Diverse and abundant arbuscular mycorrhizal fungi in ecological floating beds used to treat eutrophic water

10.21203/rs.3.rs-281997/v1 ◽

2021 ◽

Author(s):

Zhouying Xu ◽

Yichao Lv ◽

Yinghe Jiang ◽

Xiaodong Luo ◽

Xuelin Gui ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Community Composition ◽

Plant Species ◽

Mycorrhizal Fungi ◽

Aquatic Ecosystems ◽

Species Abundance ◽

Arbuscular Mycorrhizal ◽

Eutrophic Lakes ◽

Amf Diversity ◽

Amf Communities

Abstract An increasing number of investigations have demonstrated the universal existence of arbuscular mycorrhizal fungi (AMF) in aquatic ecosystems. However, little is known about the accurate distribution and functions of AMF inhabiting aquatic ecosystems, especially ecological floating bed (EFB) which was constructed for the remediation of polluted waterbodies.In this study, we collected root samples of Canna generalis, Cyperus alternifolius and Eichhornia crassipes from three EFBs floating on two eutrophic lakes in Wuhan, China, to investigate the resources and distribution of AMF in EFBs using Illumina Mi-seq technology. A total of 229 operational taxonomic units (OTUs) and 21 taxon from 348,799 Glomeromycota sequences were detected. Glomus was the most dominant AMF in the three EFBs while the second dominant AMF was related to Acaulospora. Different aquatic plant species exhibited varying degrees of AMF colonization (3.83%~71%), diversity (6~103 OTUs, 3~15 virtual taxa) and abundance (14~57551 sequences). Low AMF abundance but relatively high AMF diversity were found in C. alternifolius which is usually considered as non-mycorrhizal, demonstrating the high accuracy of Illumina sequencing. In addition, results from this study suggested a lognormal species abundance distribution was observed across AMF taxa in the three plant species, and the AMF community composition was closely related to pH, nitrogen and phosphorus.Overall, our data demonstrated that diverse and abundant AMF communities were living in EFBs, and the AMF community composition was closely related to the water quality of eutrophic lakes treated by EFBs, providing potential possibility for the applications of AMF in plant-based bioremediation of wastewater.

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Dung Beetle Diversity and Community Composition Along a Land Use Gradient in a Savannah Ecosystem of North Western Tanzania

Tropical Conservation Science ◽

10.1177/19400829211008756 ◽

2021 ◽

Vol 14 ◽

pp. 194008292110087

Author(s):

Roisin Stanbrook ◽

John Norrey ◽

Alex Wilbard Kisingo ◽

Martin Jones

Keyword(s):

Land Use ◽

Community Composition ◽

Species Abundance ◽

Dung Beetle ◽

Beetle Species ◽

Land Uses ◽

North West ◽

The North ◽

Rapid Monitoring ◽

Response Gradient

Habitat loss and degradation are the most widely cited drivers of changes in species abundance and diversity. We explored changes in dung beetle species diversity and composition across different land uses in the north west Tanzanian savannah. We expected a negative response gradient in the diversity and composition of the dung beetle community, from land uses that preserve vegetation and hold native mammal diversity to livestock intensive and heavily grazed areas. Dung beetles were sampled in a protected area and two anthropogenically influenced land use types. Species richness and composition of each land use type, including differences in diversity and functional groups were analyzed and indicator species for each land use gradient were identified. As expected, diversity and community composition varied between areas with less environmental change compared to those impacted anthropogenically. We conclude that conservation of protected areas within African savannahs can provide a functionally rich dung beetle community and subsequently rich ecological functions. The dung beetle species identified by this study as eco-indicators can be used as a benchmark for future studies that use rapid monitoring to assess disturbance in African savannas.

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Presence of a dominant native shrub is associated with minor shifts in the function and composition of grassland communities in a northern savannah

AoB Plants ◽

10.1093/aobpla/plab011 ◽

2021 ◽

Author(s):

Isaac Peetoom Heida ◽

Charlotte Brown ◽

Margarete A Dettlaff ◽

Kenneth J Oppon ◽

James F Cahill

Keyword(s):

Community Composition ◽

Spatial Scales ◽

Species Abundance ◽

Spatial Arrangement ◽

Herbaceous Plant ◽

Standing Biomass ◽

Deep Shade ◽

Understory Communities ◽

And Function ◽

Herbaceous Community

Abstract Ecosystems are spatially heterogenous in plant community composition and function. Shrub occurrence in grasslands is a visually striking example of this, and much research has been conducted to understand the functional implications of this pattern. Within savannah ecosystems the presence of tree and shrub overstories can have significant impacts on the understory herbaceous community. The exact outcomes however are likely a function of the spatial arrangement and traits of the overstory species. Here we test whether there are functional linkages between the spatial patterning of a native shrub and the standing biomass, community composition, and overall nutrient cycling of a neighbouring grassland understory communities within the Aspen Parkland of central Alberta, Canada. In a paired grassland-shrub stand study, we found the native shrub, Elaeagnus commutata, has relatively few stand-level impacts on the composition and standing biomass of the ecosystem. One factor contributing to these limited effects may be the overdispersion of shrub stems at fine spatial scales, preventing areas of deep shade. When we looked across a shrub density gradient and incorporated shrub architecture into our analyses, we found these shrub traits had significant associations with species abundance and root biomass in the understory community. These results suggest that stem dispersion patterns, as well as local stand architecture, are influential in determining how shrubs may affect their herbaceous plant understory. Thus, it is important to incorporate shrub spatial and architectural traits when assessing shrub-understory interactions.

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Spatiotemporal Dynamics of Mediterranean Shallow Coastal Fish Communities along a Gradient of Marine Protection

Water ◽

10.3390/w12061537 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1537

Author(s):

Anthony R. Marshak ◽

Just Cebrian ◽

Kenneth L. Heck ◽

Crystal L. Hightower ◽

Andrea M. Kroetz ◽

...

Keyword(s):

Community Composition ◽

Marine Reserves ◽

Marine Reserve ◽

Species Abundance ◽

Habitat Diversity ◽

Influential Factor ◽

Fish Density ◽

Southern Mediterranean ◽

Surrounding Areas ◽

Species Specific

The importance of habitat factors in designing marine reserves and evaluating their performance over time has been regularly documented. Over three biennial sampling periods, we examined the effects of vegetated coverage and habitat diversity (i.e., patchiness) on fish density, community composition, and species-specific patterns along a gradient of protection from harvest in the shallow Spanish southern Mediterranean, including portions of the Tabarca marine reserve. With the exception of two herbivores (Sarpa salpa and Symphodus tinca), vegetated cover did not significantly affect fish densities, while habitat diversity was an influential factor across all three sampling periods. Overall, fish density was more positively associated with more continuous vegetated or unvegetated habitats, and was greatest in areas of highest protection (Tabarca II – Isla Nao site). These patterns were usually observed for four abundant fish species (Boops boops, Chromis chromis, Oblada melanura, and S. salpa). Fish community composition was distinct in the most protected portion of the Tabarca reserve, where it was also most stable. Our findings align with previous investigations of the Tabarca reserve and its surrounding areas, and demonstrate its continued effectiveness in conserving fish biomass and habitat. Together with effective management, marine reserves can facilitate greater species abundance, more stable biological communities, and resilient ecosystems.

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