Variation Of Community Structure Of Plankton And Their Relationship With Environmental Factors

Artificial reef is a kind of artificial facility, which function is to improve the Marine ecological environment, build fisheries and marine ranching. Using the Qiansan Island as an example, this paper studied the effect of artificial reef on plankton through analyzing the community structure of plankton and the relationship between plankton and environmental factors, on the basis of the survey of plankton and environmental factors. Results are as follows:1.The phytoplankton species number was significant difference between reef area and control area(P<0.05), while seasonal changing trend was no significant between reef area and control area. These indicated that deployment of artificial reefs increased the number of phytoplankton species, but had no significant effect on seasonal variation of phytoplankton.2.The phytoplankton abundance of reef area was 1.17times compared with control area.3.The dominant species of phytoplankton was no significant difference and the first dominant species of four seasons was same between reef area and control area, Which led to the Shannon-Wiener index, Margalef index and Pielou evenness index were no significant difference between reef area and control area(P>0.05).4.There were 58 zooplanktons in reef area and 39 in control area. In the four seasons, every survey’s species number of zooplankton in reef area on average 1.38 times higher than in control area.5. The abundance and biomass of zooplankton in reef area were higher than in the control area. The average individual weight of zooplankton was significant difference between reef area and control area. Which were 1.70mg and 1.21mg respectively.6.The Shannon-Wiener index, Margalef index and Pielou evenness index changed obviously with the seasons, and the changing trend was no difference between reef area and control area, while there was no significant difference between reef area and control area(P>0.05)7.Based on the survey data from 2012 to 2013, by using Redundancy analysis(RDA) to study the relationship between plankton and environmental factors. The result show that the main environmental factors affecting the phytoplankton abundance were temperature, reactive silicate(SiO3-Si), dissolved oxygen(DO), reactive phosphate(PO4-P), dissolved inorganic nitrogen(DIN), BOD5, COD and transparency. The main environmental factors affecting the zooplankton abundance were reactive silicate(SiO3-Si), dissolved inorganic nitrogen(DIN), temperature, salinity, pH, BOD5, transparency and dissolved oxygen(DO).8.The relationship between plankton abundance and environmental factors was also analyzed using generalized additive model(GAM),and the results showed that the nutrient, transparency, zooplankton abundance and temperature are the main environmental factor affecting phytoplankton abundance, and nutrient is the biggest impact factor. The main environmental factors affecting the zooplankton abundance were temperature and transparency.