Diel and seasonal changes in the macrozooplankton community of a tropical estuary in Northeastern Brazil

ABSTRACT This study observed the spatial and temporal distributions of molluscs in a Halodule wrightii meadow, verifying if they respond satisfactorily to seasonal changes in this seagrass ecosystem. Twenty-four species were identified. Chitons were rare, bivalves had greater number of species (11), followed by gastropods (9) which were also the most abundant class (73%). All classes were more abundant in the belowground. The most common species was Tricolia affinis, especially in aboveground. The occurrence of some species in both strata or out of the expected stratum may have been influenced by shallow layer of the sediment considered in this study, hydrodynamic, and low biomass of the studied meadow. According to univariate and multivariate analyses, despite of molluscan descriptors had been related to variables associated with rainfall, the seagrasses had an important role on the seasonal and vertical variations of the molluscan fauna. The biomass of the epiphyte Hypnea musciformis was correlated to temporal variations of the species from aboveground, indicating its secondary role for this community. The molluscs were sensible to environmental variations, and also reflected seasonal changes of the seagrass, showing that damages on these meadows reflect even at lower levels of the marine food web.

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Assessment of Physical-Chemical Characteristics of Water and Sediments from a Brazilian Tropical Estuary: Status and Environmental Implications

The Scientific World JOURNAL ◽

10.1100/2012/676173 ◽

2012 ◽

Vol 2012 ◽

pp. 1-14 ◽

Cited By ~ 1

Author(s):

Madson de G. Pereira ◽

Marta V. A. S. de Andrade ◽

Vanessa C. Ornelas ◽

Raimunda A. N. de Almeida ◽

Maurício P. F. Fontes ◽

...

Keyword(s):

Northeastern Brazil ◽

Chemical Characteristics ◽

Tropical Estuary ◽

Total Organic Matter ◽

Environmental Standards ◽

Environmental Implications ◽

Environmental Preservation ◽

X Ray ◽

Physical Chemical

The environmental quality of the Jacuípe River's estuary (very important in northeastern Brazil) was assessed during 2007 and 2008. In water, concentrations (mg L−1) ofNO2-(<0.004 to 0.016),NO3-(0.01 to 0.33), solublePO43-(<0.02 to 0.22), dissolved oxygen (3.9 to 9.6), total contents (mg L−1) of Cd (<0.001), Cu (<0.01), Pb (<0.01), and Zn (<0.1), pH (5.60 to 8.00), and electrical conductivity (0.12 to 48.60 mS cm−1) agreed with environmental standards. In sediments, clay and total organic matter (%, m/m) varied, respectively, from 8.8 to 12.0 and from 1.1 to 8.8, while infrared, thermogravimetric profile, electronic micrograph, as well as X-Ray analyses showed desirable adsorptive characteristics. However, maximum exchangeable levels (mg kg−1) of Cd (1.3), Cu (44.6), Pb (35.7), and Zn (43.7) and their respective maximum pseudototal concentrations (mg kg−1): 19.4, 95.1, 68.2, and 30.3 were below the recommended limits. In this sense, it was possible to demonstrate good environmental preservation even with the growing number of industries and touristic activities in the evaluated estuarine area.

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Seasonal changes of the microplankton community along a tropical estuary

Regional Studies in Marine Science ◽

10.1016/j.rsma.2015.10.006 ◽

2015 ◽

Vol 2 ◽

pp. 189-202 ◽

Cited By ~ 9

Author(s):

I. Seguro ◽

C.M. García ◽

S. Papaspyrou ◽

J.A. Gálvez ◽

E. García-Robledo ◽

...

Keyword(s):

Seasonal Changes ◽

Tropical Estuary

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Reproductive biology of the protandric hermaphrodite fat snook Centropomus parallelus Poey 1860 in a tropical estuary, northeastern Brazil

Studies on Neotropical Fauna and Environment ◽

10.1080/01650521.2019.1663594 ◽

2019 ◽

Vol 54 (3) ◽

pp. 225-235

Author(s):

Daniel Alvares Silveira de Assis ◽

Danieli Marinho Nobre ◽

Marcelo Carneiro de Freitas ◽

Leonardo Evangelista Moraes ◽

Alexandre Clistenes de Alcântara Santos

Keyword(s):

Reproductive Biology ◽

Northeastern Brazil ◽

Tropical Estuary ◽

Fat Snook

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Feeding ecology of three juvenile mojarras (Gerreidae) in a tropical estuary of northeastern Brazil

Neotropical Ichthyology ◽

10.1590/1982-0224-20150039 ◽

2016 ◽

Vol 14 (1) ◽

Cited By ~ 6

Author(s):

Antônio Limeira Felinto de Araújo ◽

Renato Pereira Dantas ◽

André Luiz Machado Pessanha

Keyword(s):

Feeding Ecology ◽

Resource Partitioning ◽

Salinity Gradient ◽

Northeastern Brazil ◽

Tropical Estuary ◽

Beach Seine ◽

Opposite Pattern ◽

Main Prey ◽

Nursery Habitats ◽

Prey Items

ABSTRACT Distributions and feeding ecology of mojarra species from shallow water of a tropical estuary in Northeastern Brazil were observed aiming to investigate differences in distribution and resource partitioning among juveniles of three species of mojarras. Fishes were collected with a beach seine across four sites along a salinity gradient from January to December of 2011. Highest abundances were recorded during the rainy season in the upper and middle estuary. Microcrustaceans, mainly copepods, were the preferential prey items of all mojarras, irrespective of size or hydrological season, suggesting these areas may be important nursery habitats. Juveniles of mojarra used two important mechanisms for exploitation of resources: (1) spatial segregation along the salinity and temperature gradient, such as abundance of Eucinostomus melanopterus increased from downstream to upstream estuary, while Eugerres brasilianus displayed an opposite pattern; (2) differences related to the volumetric proportion of the main prey items, with indications that E. melanopterus and Diapterus rhombeus fed predominantly on Calanoida and Cyclopoida, while the diet of E. brasilianus was dominated by items of infauna. Such strategies were important for resource partitioning, favouring the coexistence of these three species in the estuary.

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