Study Of Ecological Distribution Characteristics Of Bacteria And Virioplankton And Their Impact Factors In The Northwest Of The Yellow Sea

The coastal economic development rapidly in recent years.Surface runoff, aquaculture pollution, oil pollution and wastewater discharge, et al, which have seriously affected the quality of coastal marine environment(Liu, et al,2001).Marine bacteria and virus of the important marine organisms in the group play an important role in the marine ecosystems and they have important ecological significance for coastal environmental quality.This paper uses the traditional culture method and fluorescence microscopy to study the ecological distribution of bacteria of spring and autumn in the Northwest of the Yellow Sea. The relationships between the ecological distribution of bacteria and environmental factors ,such as temperature, salinity and chlorophyll a content are also analyzed. At the same time,this paper studies ecological distribution of virioplankton of spring and autumn of the Northwest of the Yellow Sea using fluorescence microscopy.The relationships between the ecological distribution of virioplankton and environmental factors ,such as water depth, temperature, salinity and chlorophyll a content are also analyzed.Therefore, selecting this typical coastal area to study the bacteria and virioplankton ecological study ,which can accumulate basic information for our country marine microbiol study and more importantly,which can be hoped to provide scientific reference for pollution control and the development of ecological protection measures of the marine environment in this coastal area.The study results show that the average bacterial biomass (BB) in water of spring and autumn in this coastal area are: (14.37±7.38)mgC/m3,(6.42±3.90)mgC/m3. The average heterotrophic bacterial abundance in water of spring and autumn are: (0.77±1.21)×103CFU/cm3,(0.35±0.24)×103CFU/cm3. The average bacterial biomass (BB) in surface sediment of spring and autumn in this coastal area are: (0.44±0.21)×10-6 / (g wet weight), (0.35±0.10)×10-6gC / (g wet weight). The average heterotrophic bacterial abundance in surface sediment of spring and autumn are: (0.18±0.22)×106CFU /(g wet weight), (0.59±1.35)×106CFU/(g wet weight). The distribution of BB and heterotrophic bacteria have their own characteristics. But on the whole, the higher bacterial biomass and heterotrophic bacterial abundance also appear in the Shandong Peninsula or the Liaodong Peninsula shore, and they gradually decline offshore. The vertical distribution of BB in water of spring and autumn show that the surface > bottom. Phytoplankton is one of important factors in controlling the distribution of BB in water of spring. The BB has no correlations with temperature, salinity and phytoplankton in autumn. The vertical distribution of heterotrophic bacteria in water of spring shows that the surface < bottom. The vertical distribution of heterotrophic bacteria in water of autumn shows that the surface > bottom. The heterotrophic bacterial abundance in water of spring and autumn have no correlations with temperature, salinity, chlorophyll a in water . The BB in surface sediment of spring and autumn have no correlations with temperature, salinity, phytoplankton in bottom layer and BB of the water.The heterotrophic bacterial abundance of spring in surface sediment has highly significant correlation with salinity in bottom layer(r=-0.808,p<0.01),which has no correlations with other environmental factors. The heterotrophic bacterial abundance of autumn in surface sediment has no correlations with the known environmental factors.The study results of the ecological distribution of virioplankton and its impact factors show that the average virioplankton abundance of spring and autumn in this coastal area are: (0.65±0.74)×109particles/dm3,(0.37±0.43)×109particles/dm3. The vertical distribution of virioplankton abundance of spring shows that the bottom>surface>10m.The vertical distribution of autumn shows that the bottom>10m > surface.The horizontal distribution of virioplankton abundance of spring and autumn are similar with the distribution of the bacteria in this area. But on the whole, the higher virioplankton abundance also appears inshore, and which gradually declines offshore. Chlorophyll a and salinity are important factors in influencing the distribution of virioplankton abundance of spring. The virioplankton abundance of autumn has no correlations with water depth, temperature, salinity and chlorophyll a.