To understand the characteristics of population structure of planktonic copepods and their response mechanisms to marine environmental factors in different seasons,the community structure of planktonic copepods in samples obtained from 7 stations in artificial reefs of Wenchang,Hainan Province in March and September 2019 were investigated.A total of 33 species of planktonic copepods belonging to 23 genera within 17 families were identified in artificial reefs,with 27 species and 21 genera in spring,and 23 species and 19 genera in fall,respectively.The identified planktonic copepods were further categorized into estuarine groups,warm temperate groups,warm water coastal groups,and warm water widespread groups.The predominant species in spring were mainly composed of Temora turbinata and Canthocalanus pauper,whereas Tortanus gracilis and Subeucalanus subcrassus were dominant species in fall.The species and abundance of planktonic copepods in spring were higher than that in fall,while the diversity index and evenness were vice versa,with obvious seasonal differences.In addition,there was a correlation between the population of copepods and physicochemical environmental factors.The major warm water group of copepods in spring showed different degree of correlation with environmental factors,such as NO2-N,NH3-N,pH,water depth,temperature etc.,while the population of copepods in fall was affected by limiting factors such as dissolved oxygen,pH,and temperature.In conclusion,copepods species inartificial reefs were rich and diverse,and their community structure tended to be stable.In addition,the surrounding water quality was generally good,and the whole marine ecosystem and ecological environment were in good condition.
