Diel,seasonal,and annual variations of fish assemblages in intertidal creeks of the Changjiang River estuary  

作　　者：Jiayi FAN Jiasheng YANG Yuanwen HE Xiaodong JIANG 

机构地区：[1]State Key Laboratory Estuarine and Coastal Research,School of Life Sciences,East China Normal University,Shanghai 200241,China

出　　处：《Journal of Oceanology and Limnology》2023年第5期1849-1863,共15页海洋湖沼学报（英文）

基　　金：Supported by the Science and Technology Commission of Shanghai Municipality (Nos.21DZ1200900,22DZ1202600);the National Natural Science Foundation of China (No.31772405);the Natural Science Foundation of Shanghai (No.19ZR1416200);the Resources Monitoring Project of Shanghai Chongming Dongtan National Nature Reserve (No.CMDT-JC202101);the Yangtze Delta Estuarine Wetland Ecosystem Observation and Research Station (No.K202205);the Fundamental Research Funds for the Central Universities。

摘　　要：The use patterns of salt marsh habitats by fish assemblages were investigated in two welldeveloped intertidal creeks in the Changjiang(Yangtze)River estuary on spatial and temporal scales.Samples were collected using fyke nets at two sites during day and night in each season throughout four years.Notable changes in fish assemblages were detected over seasonal and interannual cycles,with many more marine species present in winter assemblages,whereas freshwater and estuarine species characterized the other seasonal samplings.The appearance of catadromous species in intertidal creeks mainly depended upon their specific physiological requirements,such as spawning migration.No significant diel shifts were observed in fish assemblages.This diel pattern may be a combined consequence of avian predation pressure and other drivers(i.e.,inherent living behaviors,food availability,and predation by piscivorous fishes).The spatial difference in fish community was insignificant even though the two intertidal creeks were different in size.Intertidal creeks with different size could possess similar ecological value for fish fauna.Redundancy analysis(RDA)showed that biological factors exerted greater effects on fish assemblages than physical variables.Temporal variations were strongly facilitated by food availability,but negatively impacted by avian predation.Salinity,water temperature,and river runoff had weak influence on temporal variations of fish communities.The lengthfrequency distribution showed that the fish collected in these two sites mainly consisted of young-of-year and juvenile fish,which confirmed that the creeks provided important nursery and forage roles in the process of fish ontogenetic development.Further,we proposed that salt marsh conservation management should be equally applied to all well-developed intertidal creeks regardless of creek size.

关 键 词：FISH temporal variation intertidal creeks Changjiang(Yangtze)River estuary 

分 类 号：S931.1[农业科学—渔业资源]