Population structure and reproductive biology of Uca rapax (Decapoda: Ocypodidae) in a tropical coastal lagoon, southeast Brazil

Abstract In this article, hydrographic processes of a tropical coastal lagoon is studied that control inherent biological mechanisms of the lagoon environment. Realizing the interest of environmentalists over physio-chemical studies of a wetland tropical wetland system on the western boundary of the Bay of Bengal, a high-resolution intensive vertical hydrographic field campaign was carried during monsoon to uncover peculiarity in vertical hydrographic processes that was long-awaited to address many environmental issues. Vertical hydrographic profiles on spatio-temporal scale were made at nine stations in a zonal direction of the Chilika lagoon system. Results of vertical variability of salinity showed the presence of higher saline water over less saline water in the central-western region. The higher and lower water temperature in the western and eastern parts of the lagoon, respectively, indicated temperature dipole between the two regions. The encapsulation of water mass having higher temperature by the water of lower temperature at the central region resulted evolution of thermal inversion. The highest dissolved oxygen concentration was observed in the sub-surface layers of the western part of the lagoon. However, a layer of near-hypoxia occurred below 1.5 m depth in the central region. This study proposes comprehensive inter-seasonal studies to address the vertical variability of biogeochemical parameters and the fate of organic flux.

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Sources and internal cycling of dissolved barium in a tropical coastal lagoon (Chilika lagoon, India) system

Marine Chemistry ◽

10.1016/j.marchem.2021.104083 ◽

2022 ◽

pp. 104083

Author(s):

Mohd Danish ◽

Gyana Ranjan Tripathy

Keyword(s):

Coastal Lagoon ◽

Chilika Lagoon ◽

Tropical Coastal Lagoon ◽

Internal Cycling

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Population structure and reproductive biology of Metamysidopsis neritica (Crustacea: Mysidacea) in a sand beach in south Brazil

Revista Brasileira de Zoologia ◽

10.1590/s0101-81752008000300004 ◽

2008 ◽

Vol 25 (3) ◽

pp. 403-412 ◽

Cited By ~ 11

Author(s):

Patrícia Calil ◽

Carlos A. Borzone

Keyword(s):

Population Structure ◽

Reproductive Biology ◽

Direct Relationship ◽

Surf Zone ◽

Population Characteristics ◽

Egg Volume ◽

Sand Beach ◽

The World ◽

Egg Number ◽

South Brazil

Mysidacea are common sublittoral crustaceans that inhabit all coasts in the world. In this study, the population characteristics and the reproductive biology of Metamysidopsis neritica Bond-Buckup & Tavares, 1992 were studied in the surf zone of a south Brazilian beach (Atami). Mysids were sampled at monthly intervals from August, 1999 to July, 2000 (total of 29,490 individuals). Individuals were classified into six population categories. The highest abundance occurred in May (8,665) and August (6,415), and lowest in September (336) and December (368). Three main generations were identified, namely the summer, fall and winter generations. The winter generation was the longest (four to five months). The fall generation lasted four months, and the summer one extended from three to four months. Ovigerous females occurred throughout the year, with a greater proportion in July. The number of eggs or larvae varied from one to 16. Weak associations were found between female length and egg number, egg volume, and the number of larvae with and without eyes. Egg volume increased during the coldest season, whereas the smallest values were recorded during summer. These results suggest a possible direct relationship between egg volume and generation longevity.

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