Ecological Studies of Odonata Population in Northern Sumatra, Indonesia

Abstract

Odonata is importants insect groups in the world. Ten ha rice field plot in three sites in Manik Rambung Rice Field (MRRF), Simalungun District, North of Sumatera (latitude: 2°53‘ 52.8"N and longitude: 99° 00‘24.4"E, about 90 km from Medan City at 594 - 602 masl) were recorded of Odonata population. The farmers have rice culture practices, combine with fish farming during season paddy planting. The comparison was conducted which nine stations of green Campus areas with purpossive randomsampling in a month (November, 1. 2011 until November, 28. 2011) using sweep net (400 μm mesh, 60cm x 90cm) which six swings started from 0900 to 1200 for collection of Odonata. The results were collected 445 individuals from sub-order Zygopteran and 892 individuals from sub order Anisoperan, 3 families, and 19 species of adults Odonata were identified IN MRRF. Family Coenagrionidae (Zygoptera) were dominant by Agriocnemis femina, A. pygmaea, and Ischnura senegalensis. Only Ictinogomphus decoratus recorded fromGomphidae and 11 species from Libellulidae. While two sub order, 4 families, 26 genera, 31 species and 436 individuals of Odonata identified in green campus, USU, Sumatera Utara, Indonesia. In MRRF, the ecological indices were calculated with score H‘ (0.88 - 2.50), Index Simpson (1-D) recorded were 0.49 until 0.99, while index Jaccard with 0.60-1.00. While Diversities indices Shannon and Evenness Pilou of Odonata in Campus USU was lower recorded in Station 7 and Station 1, while the highest were collected in Station 3 and Station 6. The diversities and evenness Odonata species were varied (H‘=2.20-3.42 and E=0.55-0.78). Comparison to the eveness and richness of Odonata species in each stations were differences, which effected by natural habitat, heterogenous vegetations of plants, time and weather while taken sampling, biotic, physics, and chemicals factors in environmental system are varied.