Biological Factor Monitoring Of Sea Water And Taxonomy Of Red Tide Algae In Hong Sha Harbor

Hong Sha Harbor with water area of 4km2 and volume of 1.2×107 ~1.6×107 cubic meters is one of the most important port in San Ya , the city of Hai Nan province . Our research group had finished study on the structure ecosystem and field monitoring, Covering phytoplankton,microorganisms,nutrients etc, This paper will describe in more detail in the comprehensive survey of microorganisms, phytoplankton ecology and the occurrence of red tide in the course of the investigation findings. Evaluated and analysed the ecological background and the status of the ecological environment of the occurrence of red tide with the ecological point, in order to provide the basic parameters for study the ecological and oceanographic mechanisms of red tide and formulate preventive measures.Through this investigation,we identified 43 species representing 23 genera.A- mong these, Bacillariophyta (30 species,representing 14 genera)accounted for 70%; followed by dinoflagellates(11 species,representing 7 genera)accounted for 26%; Bacillariophyta were the largest group ,in which the dominant population in the area was Skeletonema coatatum,and it accounted for 68.6% of the total phytoplankton. Therefore the horizontal and seasonal distributions patterns of Skeletonema coatatum dominated the patterns of the total phytoplankton.In the spatial distribution, species, the diversity index (H') and evenness(J) of phytoplankton community increased gradually from inside of the harbor to outside of the harbor; The density of total cell number and Chlorophy ll a increased from outside of the harbor to inside of the harbor. In the time distribution , the monthly averages the density of phytoplankton and Chl.a showed two peaks.During the investigation, Phytoplankton cells in the total number of overall average of 1.50×10~6cells/L ; the values of chlorophyll a in the range of 0.23~9.9μg/L , with overall average of 2.89μg/L. belonging to a higher level; the diversity index (H') in the range of 0.05~3.16, with overall average of 1.39; the evenness(J) in the range of 0.03~0.88; with overall average of 0.46.In the area , heterotrophic bacteria and coliform bacteria of sea water exceed serious , this showed the water be polluted. Addition , phytoplankton community with a low types ,high-density characteristics and phytoplankton community structure is simple. there is the potential outbreak of red tide .during the investigation period, a harmless red tide occurred , The causative species was Skeletonema coatatum.