Annual Survey And Analysis Of Plankton Communities In Jinsha Bay, Haikou

An annual survey of plankton communities was carried out at three sites seasonally from 2017 to 2018 in the offshore marine areas of Jinsha Bay in Haikou,the capital of Hainan Province.Marine plankton biodiversity indecies,water eutrophication and organic pollutant indices were calculated to monitor the waters of the Jinsha Bay.Analysing by SPSS and Canoco to investigate the situation and grasp the development trends of spatial and temporal distribution characteristics of this ecological environment,which helps to build up the fundamental database.A total of 63 species of phytoplankton were collected among these surveys.Bacillariophyta accounted for the highest proportion,with 42 species,then is pyrophyte,with 15 species and least is the cryptophyta.14 species red tide algae were also found.The results of the annual survey of the Jinsha Bay show that there are insufficient species of phytoplankton in Jinsha Bay,and the structure of species of phytoplankton is simple.The species composition is mainly Bacillariophyta and Pyrophyte.The season with the most phytoplankton species is spring in 2018.Four species of 38 species(genus)were found.The season with the least plankton species was winter of 2018.Only three species(genus)were found.Above all,there are 14 red tide algae was found,among which the toxic algae,Dinoflagellate algae is included.Although the occurrence of red tide algae is mostly dominant species,its abundance does not meet the standards of red tide outbreak.But the emergence of a large number of dinoflagellate and green algae of phytoplankton is also a warning to the terrible shifts in the water ecosystem.A total of 31 species of zooplankton were collected,including the largest number of copepods with 13 species,5 protozoa,4 species of planktonic larvae,and tunicates,rotifers,mollusks,edulis and ostracods each.A total of 11 dominant species were collected,copepods is the most dominant with 7 species.The emergence of protozoa and rotifers indicates that the Jinsha Bay is in a state of pollution.Most of the water quality factors in the Jinsha Bay sea area are conforming to the national second-class seawater.The transparency is relatively unstable.When the transparency worst,it is only 25cm.From the summer of 2018,the concentration of suspended solids in the Jinsha Bay increases sharply,and even exceeded the second class,the increase in suspended solids concentration is corresponding to the results of transparency.In our survey,the concentration of DIP(dissolved inorganic phosphorus)dropped to the fourth class.Correlation analysis shows that the water eutrophication indecies and organic matter pollution indecies in the Jinsha Bay sea area were dominated by DIP.Canoco analysis shows red tide algaes is corresponding with certain factor.The result of water quality factor shows that the water in Jinsha Bay is in a state of mild pollution.Meanwhile,the coral transportation indicates sea water of this area turning worse from 2017 to 2018.Much more attention should put in preservation and protection.