Population structure study of Anzali wetland zooplankton

Anzali wetland is one of the most important places for spawning fishes and zooplankton groups are the first consumer in this ecosystem. They are the perfect food for the larvae of fishes. Zooplankton status was evaluated in 6 stations of different areas of the Anzali wetland during March 2011 to February 2012. Sampling was done by tube (PVC) and passing through of 30 micron planktonic net. The samples were identified and counted by invert microscope. According to the results were identified 60 Genus and 6 phylum (11, 31, 10, 2, 1, 1, 1, 2 genus of phylum Protozoa, Rotatoria, Arthropoda, Gastrotricha, Mollusca, Tardigrada, Nematoda, Porifera, Annelida) respectively. The results showed that the maximum annual average density of zooplankton was observed with 2497 number per liter in Karkan station and the population was more in the summer than in other seasons. Phylum of Rotatoria,, protozoa and superclass Copepoda formed 48, 45 and 6percent of the density respectively. According to the results the population of zooplankton did not change much compared to past studies, excluding Protozoa but the diversity of all zooplankton group are declined very much. According to the statistical analysis Kruskal Wallis are not significant differences between density of zooplankton in different stations, months and seasons (p > 0.05), but significant differences were found in different phylum together (p