Phytoplankton Community in the Pasak Jolasid Reservoir, Lop Buri Province

Abstract

          Qualitative aspect of the phytoplankton of Pasak Jolasid reservoir was studied during 2002. A total of 159 species and 81 varieties was recorded. Phytoplankton samples were collected by towing plankton nets of three mesh sizes 22, 40 and 100 μⅿ at 29 stations. Green algae (Class Chlorophyceae) comprised the majority of species number with 54%, and followed by euglenoids (Class Euglenophyceae) with 17%. Other groups in decreasing number were Class Cyanophyceae, Class Bacillariophyceae, Class Dinophyceae, Class Xanthophyceae and Class Chrysophyceae. Important genera were Scenedesmus, Pediastrum, Crucigenia, Closterium, Tetraedron, Coelastrum, Trachelomonas and Phacus. Temporal and spatial variation in species numbers were not significantly different (P<0.05) in this study.