Abstract

In order to understand the distribution characteristics melania snail in Hantan River watershed, from May to October 2012, 20 points from the upper stream to the lower stream of the Hantan River watershed were investigated. A total of 5 species of melania snail appeared, and in Sagok Stream, which is the primary stream in the Hantan River, Semisulcospira libertina, S. gottschei, S. coreana appeared, and S. coreana was dominant. In the secondary stream, Namdae Stream , S. gottschei and S. coreana appeared, and the dominant species was S. gottschei. In the main stream of the Hantan River, S. libertina and Koreanomelania nodifira appeared, and S. libertina were dominant. The differences in the species appearing according to the physical characteristics of the rivers were found in the S. libertina, and the flow velocity was less than 20 cm/sec, and S. gottscheri, the bed of sand and pearl. The flow velocity is less than 10 cm/sec, S. coreana has a flow velocity of 10 cm/sec-40 cm/sec with the river bed of pebble, and K. nodifira has a flow velocity of 40 cm/sec or more with the bottom of the boulder, K. globus ovalis appeared at high frequency in boulder riverbeds and in river environments of 50 cm/sec or more, respectively, and the distribution characteristics were similar in the difference in water depth. In this study, it was possible to confirm the river environment preferred by each species, mainly according to the difference in the river bed and flow velocity.