Comparative fish community structure among different types of enclosures of estuarine environments

Abstract

This study explores the differences of fish assemblages in three macrotidal estuaries of Man-gyeong River Estuary (MRE), Geum River Estuary (GRE), and Han River Esturay (HRE) with similar ranges of seasonal water temperature that are diked with different levels of disconnection from freshwater discharge. The distribution of major species in the three estuaries could generally be grouped into three distinctive patterns based on their cumulative distribution with respect to the salinity gradient. The MRE was geographically closer to the GRE than to the HRE, but the fish community of the MRE more closely resembled that of the HRE. Increased freshness of the water inside the dike and the limit of coastal fish to the river may have led to this result. The results provide clues to how enclosure patterns of estuarine waters could affect fish communities over a long-term period. In addition, the information may provide guidance for how a fish community may return once environmental conditions are restored. © 2021 Shanghai Ocean University