S:Odonata larvae were sampled from 16 tributaries of Kerian River in the Kerian River Basin (KRB) using a kick sampling technique from September 1998 to May 1999 encompassing both rainy and dry seasons. The distributi...S:Odonata larvae were sampled from 16 tributaries of Kerian River in the Kerian River Basin (KRB) using a kick sampling technique from September 1998 to May 1999 encompassing both rainy and dry seasons. The distribution of odonate genera was significantly different (F 15,16 =3.99) among rivers in both seasons (F 15,16 =4.70) at P=0.05. However, no seasonal influence was detected. Protoneuridae and Libellulidae were the most dominant families in this basin. Other families Gomphidae, Coenagrionidae, Macromiidae, Chlorocyphidae and Calopterygidae, were common but Aeshnidae and Eupheidae were rare. Several common species, Prodasineura autumnalis, Brachythemis contaminata, Macromia gerstaeckeri, Paragomphus, Orthetrum brunneum, Rhinocypha quadrimaculata and Copera marginipes were identified. The calculated values of biological indices (H’, D, E, R 1 and R 2) showed that the dragonfly fauna in this river basin was slightly poor. Varied physico-chemical parameters of the river possibly as a result of human activities in surrounding areas were found to influence the distribution of the dragonfly larvae in the KRB. This study showed that the KRB provided favorable habitats for Protoneuridae and 1Libellulidae. Two most dominant species Prodasineura autumnalis and Brachythemis contaminata were obviously favoured slightly acidic water of the Kerian river tributaries.展开更多
文摘S:Odonata larvae were sampled from 16 tributaries of Kerian River in the Kerian River Basin (KRB) using a kick sampling technique from September 1998 to May 1999 encompassing both rainy and dry seasons. The distribution of odonate genera was significantly different (F 15,16 =3.99) among rivers in both seasons (F 15,16 =4.70) at P=0.05. However, no seasonal influence was detected. Protoneuridae and Libellulidae were the most dominant families in this basin. Other families Gomphidae, Coenagrionidae, Macromiidae, Chlorocyphidae and Calopterygidae, were common but Aeshnidae and Eupheidae were rare. Several common species, Prodasineura autumnalis, Brachythemis contaminata, Macromia gerstaeckeri, Paragomphus, Orthetrum brunneum, Rhinocypha quadrimaculata and Copera marginipes were identified. The calculated values of biological indices (H’, D, E, R 1 and R 2) showed that the dragonfly fauna in this river basin was slightly poor. Varied physico-chemical parameters of the river possibly as a result of human activities in surrounding areas were found to influence the distribution of the dragonfly larvae in the KRB. This study showed that the KRB provided favorable habitats for Protoneuridae and 1Libellulidae. Two most dominant species Prodasineura autumnalis and Brachythemis contaminata were obviously favoured slightly acidic water of the Kerian river tributaries.
