Mollusc diversity in the plant genetic protection area of Srinagarind Dam, Sisawat District, Kanchanaburi Province

Abstract

Kanchanaburi province harbours many kinds of molluscs due to its geographic location at the center of two zoogeographical zones and humid climate. In this study, land molluscs (i.e. live and dead specimens) were sampled monthly by a combination of quadrat sampling technique using PVC frame (1x1 m²) and leaf litter/topsoil sieving technique along five trails in every 100 meters, whereas, aquatic molluscs were collected by hands at three aquatic sites (20-minute search each). The sampling was conducted from November 2008 to October 2009 in the Plant Genetic Protection Area of Srinagarind dam, Sisawat district, Kanchanaburi province. In total, 861 individuals of molluscs representing 11 families, 13 genera, 14 species, and 4 subspecies were found. The three most abundant species were Cyclophorus siamensis Sowerby, 1850 (17.77 %), Cryptozona siamensis Pfeiffer, 1856 (16.72 %), and Anentome helena Philippi, 1847 (13.24 %), respectively. Our result revealed a high Shannon-Weiner diversity index (H' = 2.27) meaning molluscs were distributed more equitably among species. Low species richness probably resulted from the proximity of the study area to the nearby human community, where disturbance frequently occurs.