Is meiofauna community structure in Artificial Substrate Units a good tool to assess anthropogenic impact in estuaries?

The composition and distribution of the benthic meiofauna assemblages of the Nuevo Gulf (Chubut, Argentina) are described in relation to abiotic variables. The meiofauna and sediment samples were collected in the intertidal zone of four sandy beaches with different anthropic disturbances in June 2005. The samples were obtained at 20 sampling sites using a 2.5 cm diameter core tube at a depth of 10 cm. A total of 13 meiofauna taxa were identified, with the meiofauna being primarily represented by nematodes, gastrotrichs, ciliates and polychaetes and the meiofauna abundances ranging from 1.5 × 10³ to 6.5 × 10³ ind. 10 cm‑2. Univariate (one-way ANOVA test) and multivariate (ANOSIM/MDS test) analyses showed clear dissimilarities in community structures between sites with anthropic effects and those in pristine condition, revealed by the significant differences were found between beaches near to and far way from a city with port activity. The meiofaunal assemblage varied in abundance and diversity, and these changes in the community structure may have been related to environmental gradients on the shore. The BIO‑ENV analysis showed that the redox potential discontinuity depth might be the main factor in the spatial distribution of organisms.

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How do food sources drive meiofauna community structure in soft-bottom coastal food webs?

Marine Biology ◽

10.1007/s00227-018-3419-7 ◽

2018 ◽

Vol 165 (10) ◽

Cited By ~ 2

Author(s):

L. H. van der Heijden ◽

J. Rzeznik-Orignac ◽

R. M. Asmus ◽

D. Fichet ◽

M. Bréret ◽

...

Keyword(s):

Community Structure ◽

Food Webs ◽

Food Sources ◽

Soft Bottom ◽

Meiofauna Community

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The influence of prolonged drought and anthropogenic impact reversal on fish community structure and ecosystem state cycling of Lake St Lucia, Africa’s largest estuarine lake

African Journal of Aquatic Science ◽

10.2989/16085914.2019.1661825 ◽

2020 ◽

Vol 45 (1-2) ◽

pp. 167-182 ◽

Cited By ~ 1

Author(s):

D Cyrus ◽

Q Schutte ◽

L Vivier

Keyword(s):

Community Structure ◽

Anthropogenic Impact ◽

Fish Community ◽

Fish Community Structure ◽

Prolonged Drought ◽

Ecosystem State

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Effects of the burrowing crab Chasmagnathus granulata (Dana) on meiofauna of estuarine intertidal habitats of Patos Lagoon, Southern Brazil

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132005000200014 ◽

2005 ◽

Vol 48 (2) ◽

pp. 267-274 ◽

Cited By ~ 11

Author(s):

Leonardo Cruz Rosa ◽

Carlos Emilio Bemvenuti

Keyword(s):

Community Structure ◽

Salt Marsh ◽

Southern Brazil ◽

Patos Lagoon ◽

Chasmagnathus Granulata ◽

Meiofauna Community ◽

Intertidal Habitats ◽

Crab Chasmagnathus Granulata ◽

Burrowing Crab

This study aimed to evaluate the effects of the burrowing crab Chasmagnathus granulata on meiofauna at three intertidal habitats across a tidal exposure gradient (i.e., an emerged salt marsh, an emerged mudflat and a submerged mudflat) in an estuarine embayment of Patos Lagoon, Southern Brazil. Meiofauna community was dominated by nematodes and ostracods, following by copepods and turbellarians. Densities of all studied organisms varied significantly among habitats. Highest values were observed in submerged mudflat while lower in salt marsh. Nematodes were unaffected by crab in either habitat, whereas ostracod, copepod and turbellarian densities were significantly lower in disturbed than control areas in both mudflat habitats. Any meiofaunal group was affected in salt marsh, probably due to a less intense disturbance. The results showed that the burrowing crab C. granulata could play an important role on meiofauna community structure in estuarine intertidal habitats of Patos Lagoon, because crab disturbance seemed to affect mainly surface populations, especially in mudflat. However, the meiofauna response to crab disturbance was variable among habitats depending of the intensity and the frequency of the disturbance.

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Initial Colonization of Artificial Substrate: Community Development and Structure Studied by Scanning Electron Microscopy

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f81-184 ◽

1981 ◽

Vol 38 (11) ◽

pp. 1371-1384 ◽

Cited By ~ 89

Author(s):

Christiane Hudon ◽

Edwin Bourget

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Community Structure ◽

Community Development ◽

Species Interactions ◽

Light Availability ◽

Artificial Substrate ◽

Lawrence Estuary ◽

Cell Densities ◽

Scanning Electron

The initial phases of subtidal and intertidal community development were observed using scanning electron microscopy on samples from plastic panels immersed monthly in the St. Lawrence Estuary.Bacteria and diatom populations were quantitatively evaluated on samples collected from May to November, 1978. The pattern of immersion and/or periodical emersion according to the level greatly influenced the community structure. Subtidal panels (−5.0 m) were rapidly colonized by bacteria while diatoms settled 2–7 wk later, depending on the season. Cocconeis spp. and Amphora spp. were the major diatom colonizers until mid-August. In September, Synedra tabulata settled on the panels. Until mid-September, all dominant species formed well-defined, generally monospecific clumps. In contrast with Cocconeis spp. and Amphora spp., which lie horizontally on the surface, S. tabulata, which is needlelike in shape, formed erect fan-shaped colonies. Other late invaders possessed a mucus stalk, raising themselves from the surface and thus better utilizing the vertical dimension. Clump overlap and increased species interactions occurred with higher cell densities. In the intertidal zone bacteria settled after 8–12 wk while Achnanthes brevipes var. parvula appeared after 20 wk, the only diatom species able to resist semidiurnal emersion. The ability of the panels to retain water through detritus and irregularities is probably the main factor allowing the development of this community. Panels emersed only at spring tides (monthly) were rapidly colonized by bacteria, and heavy diatom settlement occurred within 4 wk. Successive monthly emersions eliminated or strongly reduced diatom populations, which were replaced by filamentous (Ectocarpaceae) algae. The three types of communities are compared and the strategic advantage of upright forms is discussed in relation to population density, light availability, and detrital cover.Key words: St. Lawrence Estuary, artificial substrate, community structure, community development, Cocconeis spp., Synedra tabulata. Amphora spp., diatoms

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Response of estuarine meiofauna assemblage to effects of fertilizer enrichment used in the sugar cane monoculture. Pernambuco, Brazil

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592009000100005 ◽

2009 ◽

Vol 57 (1) ◽

pp. 43-55 ◽

Cited By ~ 15

Author(s):

Paulo J. P. Santos ◽

Mônica L. Botter-Carvalho ◽

Ananias B. do Nascimento-Júnior ◽

Raquel G. C. Marinho ◽

Paulo V. V. C. Carvalho ◽

...

Keyword(s):

Community Structure ◽

Sugar Cane ◽

Low Dose ◽

Environmental Parameters ◽

Experimental Period ◽

High Dose ◽

Meiofauna Community ◽

Taxonomic Groups ◽

Nitrogen Phosphorus

In situ application of inorganic fertilizer was used to simulate environmental eutrophication associated with the sugar cane monoculture. Meiofauna community structure is herein used to assess this experimental impact. Nine quadrangular areas (4m² each) were randomly defined in the midlittoral estuarine area. Three of these areas received a high dose of sugar cane fertilizer (375 g/m² Nitrogen-Phosphorus-Potassium), three areas received a low dose of the fertilizer (187.5 g/m²) and the other three areas represented the control. The fertilizer was applied every week. Environmental parameters and meiofauna were sampled using three-to-four week intervals. Six samplings were subsequently performed maintaining this interval. Meiofauna was counted and identified to major taxonomic groups. Meiofauna community structure varied throughout the experimental areas. Control areas maintained their abundance values during the study period, but within the enriched areas meiofauna abundance decreased greatly. MDS and ANOSIM analysis showed significant variation in the meiofauna community structure among experimental areas and also along the experimental period in the enriched areas.

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