Rockpool ichthyofauna of Amazon coastal zone: spatial and environmental effects on species distribution

2017 ◽  
Vol 68 (6) ◽  
pp. 1137 ◽  
Author(s):  
Tiago Octavio Begot ◽  
Bruno Eleres Soares ◽  
Leandro Juen ◽  
Luciano Fogaça de Assis Montag
Keyword(s):  
Community Structure ◽  
Coastal Zone ◽  
Intertidal Zone ◽  
Fish Assemblages ◽  
Sandy Beaches ◽  
Tidal Range ◽  
Spatial Variables ◽  
Β Diversity ◽  
Principal Factors

The present study analysed the effects of environmental and spatial variables on the structure of fish communities inhabiting rockpools in the Amazon coastal zone to test the hypothesis that environmental characteristics and spatial distribution are the principal factors responsible for community structure. In all, 80 pools were sampled, 40 in the rainy season and 40 in the dry season. The pools were located on five sandy beaches of the Amazon coast. In all, 1303 fish were collected, representing 20 taxa distributed in nine orders and 14 families. The abundance and occurrence of different taxa varied considerably, as did β diversity, ranging from identical to completely different communities. Differences were found in taxa abundance between seasons (rainy and dry) and beach locality. However, for species richness, only differences between seasons were found, showing the effects of spatial and environmental variation in the structure of fish assemblages. This corroborates both spatial and environmental hypotheses of community structure, and reinforces the role of the extreme dynamic conditions, such as tidal range and influence of the rivers that flow into this estuary, in the intertidal zone fish on the Amazon coast.

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

2017 ◽  
Vol 68 (11) ◽  
pp. 2115 ◽  
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.

scholarly journals Effect of waterfalls and the flood pulse on the structure of fish assemblages of the middle Xingu River in the eastern Amazon basin

2015 ◽  
Vol 75 (3 suppl 1) ◽  
pp. 78-94 ◽  
Author(s):  
TAP Barbosa ◽  
NL Benone ◽  
TOR Begot ◽  
A Gonçalves ◽  
L Sousa ◽  
...  
Keyword(s):  
Amazon Basin ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Flood Pulse ◽  
Total Dissolved Solids ◽  
Total Suspended Matter ◽  
Xingu River ◽  
Temporal Factors ◽  
Principal Factors

Abstract The structure of fish assemblages in Neotropical rivers is influenced by a series of environmental, spatial and/or temporal factors, given that different species will occupy the habitats that present the most favourable conditions to their survival. The present study aims to identify the principal factors responsible for the structuring of the fish assemblages found in the middle Xingu River, examining the influence of environmental, spatial, and temporal factors, in addition to the presence of natural barriers (waterfalls). For this, data were collected every three months between July 2012 and April 2013, using gillnets of different sizes and meshes. In addition to biotic data, 17 environmental variables were measured. A total of 8,485 fish specimens were collected during the study, representing 188 species. Total dissolved solids, conductivity, total suspended matter, and dissolved oxygen concentrations were the variables that had the greatest influence on the characteristics of the fish fauna of the middle Xingu. Only the barriers and hydrological periods played a significant deterministic role, resulting in both longitudinal and lateral gradients. This emphasizes the role of the connectivity of the different habitats found within the study area in the structuring of its fish assemblages.

scholarly journals Study on Community Structure of Commercial Sea Cucumber in Intertidal Zone, Southeast Moluccas, and Tual, Moluccas

2020 ◽  
Vol 12 (1) ◽  
pp. 31
Author(s):  
Jasmadi Jasmadi ◽  
Ismiliana Wirawati ◽  
Indyaswan Tegar Suryaningtyas ◽  
Sandi Permadi
Keyword(s):  
Water Quality ◽  
Community Structure ◽  
Intertidal Zone ◽  
Sea Cucumber ◽  
Diversity Index ◽  
Target Area ◽  
Resources Management ◽  
Species Analysis ◽  
Evenness Index

HighlightEight species of sea cucumber was found in four intertidal location in Southeast Moluccas and Tual watersHolothuria atra had the highest densitySea cucumber biodiversity in Southeast Moluccas and Tual waters categorized as lowLocal culture can be used for sustainability of sea cucumber resources management  AbstractA study on the community structure of sea cucumber in Southeast Moluccas and Tual needs to be done due to the important role of sea cucumber in both ecologically and economically sustainability. This study aimed to investigate the community structure of sea cucumber in this region as one of the supporting information for the utilization and management of the resources. A survey was conducted by sweeping the target area, by walking and also snorkeling. The location where each sea cucumber found was marked using a GPS, the specimen was weighed, and some were preserved for species analysis. Water quality was measured at each location, while the substrate and vegetation were recorded. This study revealed different composition of species in the investigated area. As many as 8 species of sea cucumber were found, in which four were of genus Holothuria, three were of genus Stichopus and the rest were of genus Bohadschia. Species H. atra has the highest density. In general, the diversity index was relatively low (< 2), the evenness index was 0-81 indicating that the community was depressed. Certain species dominated at most of the investigated sites (0.50-1), and a low margalef index is 0-1.7. To conclude, the community structure of sea cucumber in Tual and Southeast Moluccas was in a depressed condition.

scholarly journals Community structure and diversity of demersal fish assemblages: the role of fishery

2004 ◽  
Vol 68 (S1) ◽  
pp. 215-226 ◽  
Author(s):  
Mary Labropoulou ◽  
Costas Papaconstantinou
Keyword(s):  
Community Structure ◽  
Fish Assemblages ◽  
Demersal Fish

Urban Wastewater Discharge and Bacteriological Quality of Receiving Coastal Waters: Processes and Modelling

1993 ◽  
Vol 27 (12) ◽  
pp. 223-226
Author(s):  
J.-F. Guillaud ◽  
M. Pommepuy ◽  
E. Dupray ◽  
J.-C. Salomon ◽  
B. Thouvenin
Keyword(s):  
Coastal Zone ◽  
Coastal Waters ◽  
Wastewater Treatment Plants ◽  
Enteric Bacteria ◽  
Wastewater Discharge ◽  
Urban Wastewater ◽  
Bacteria Transport

The aim of this paper is to present some results of bacterial studies which were developed by IFREMER in coastal discharge areas of urban wastewaters; they are focused on the determination of bacterial inputs by wastewater treatment plants, the role of environmental factors on the enteric bacteria survival in the coastal zone, and the modelling of bacteria transport and disappearance in order to provide useful management information for minimizing faecal pollution in the coastal zone.

The Riddle of the Sands

2017 ◽  
Author(s):  
Daniel Brayton
Keyword(s):  
Coastal Zone ◽  
North Atlantic ◽  
Intertidal Zone ◽  
Nation State ◽  
Narrative Fiction ◽  
Aesthetic Appeal ◽  
Secret Service ◽  
German Coast ◽  
The Aesthetic ◽  
Modern Nation State

The aesthetic appeal of coasts is due in part to the indeterminacy of the intertidal zone. The imagination finds room to play where land and sea meet. This chapter explores the coastal zone that lies at the heart of a novel considered by many to be the first modern spy thriller, Erskine Childers’s The Riddle of the Sands: A Record of Secret Service. Childers develops the notion of coastal indeterminacy as a figure for the boundaries, ambitions, and limitations of the modern nation-state. The journey of Childers’s characters through a north Atlantic archipelago that extends from the German coast draws a line of association between Europe and Britain, whose form depends on coastlines, estuaries, and shallows. In following this course, Childers creates a narrative fiction that shifts between charts, borders, and languages.

scholarly journals Arthropod community structure in pastures of an island archipelago (Azores): looking for local–regional species richness patterns at fine-scales

2004 ◽  
Vol 94 (2) ◽  
pp. 111-121 ◽  
Author(s):  
P.A.V. Borges ◽  
V.K. Brown
Keyword(s):  
Species Richness ◽  
Regional Scale ◽  
Local Scale ◽  
Local Species Richness ◽  
Β Diversity ◽  
Arthropod Species ◽  
Α Diversity ◽  
Local Species ◽  
Richness Patterns

AbstractThe arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local–regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= α diversity) and regional species richness was estimated at the pasture level (= γ diversity) with the ‘first-order-Jackknife’ estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of α and β diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing β-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

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