Effects of Hypoxia on the Distribution of Calanoid Copepod Eggs in the Seabed Sediments of the Eutrophic Masan Bay, Korea

In this study, we investigate the distribution of calanoid copepod eggs in the sediments of Masan Bay (South Sea, Korea), in which hypoxic conditions occur every summer. In August (2011), hypoxia was observed at all stations, while normoxia was observed in April (2012). The pH and hydrogen sulphide...

Description complète

Enregistré dans:
Détails bibliographiques
Auteurs principaux: Seo Yeol Choi, Bonggil Hyun, Pung-Guk Jang, Kyoungsoon Shin, Ho Young Soh, Jung-Hoon Kang, Min-Chul Jang
Format: article
Langue:EN
Publié: MDPI AG 2021
Sujets:
Accès en ligne:https://doaj.org/article/7df65573d4b54275a5aad38bfe389b3c
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
Description
Résumé:In this study, we investigate the distribution of calanoid copepod eggs in the sediments of Masan Bay (South Sea, Korea), in which hypoxic conditions occur every summer. In August (2011), hypoxia was observed at all stations, while normoxia was observed in April (2012). The pH and hydrogen sulphide concentration at the sediment-water interface in the inner bay during August were 7.7 and >20 mol L<sup>−1</sup>, respectively, and there was no significant difference between the stations in April. The abundance of eggs in the sediment ranged from 0.69 to 1.49 × 10<sup>6</sup> eggs m<sup>−</sup><sup>2</sup> in August, and from 0.59 to 1.08 × 10<sup>6</sup> eggs m<sup>−2</sup> in April. Notably, the proportion of abnormal eggs was high (a maximum of 77.1%) in August, and a uniform distribution of normal eggs (>80%) was observed in April. A generation of abnormal eggs hatched with deformed nauplii in Masan Bay during the summer, and a failure to hatch was likely due to the high H<sub>2</sub>S concentration and low pH caused by hypoxia. In this paper, we discuss the effects of hypoxia and seabed environments on the hatching success of calanoid copepod eggs.