Spatial Colonization Dynamics Of Micronecta Scutellaris And Coexisting Aquatic Insects In Tropical Ponds And Lakes

Occurrence, prevalence and distribution of representative key species of aquatic heteroptera were investigated in selective fresh water bodies at Kancheepuram and Chennai districts of Tamilnadu. Traditional unrestricted sampling method was adopted. Water bodies with silt loam substratum showed higher correlation with abundance of aquatic bugs than with sandy loam, loamy sand, clay loam and clay. Taramani pond with clayey substratum was not colonized by M. scutellaris. Soil organic matter influences the colonization of bottom region of shore water resulting in dominance of M. scutellaris in permanent habitats. Permanent pond at Chetpet, Chennai having silt loam (silt 55 %, sand 25% and clay 20%) soil substratum and 10.2 % organic carbon showed abundance of aquatic bugs. The first two consecutive positions in community structure indices are shared by permanent pond ecosystems followed by temporary pond community. Species diversity index represents equitability in species abundance among species. Chengalpet permanent pond exhibits very poor species diversity index in spite of having high species abundance next to Chetpet pond. Habitat stability and abundance of niches influence colonization dynamics. In newly formed habitats, through climate change, the bugs colonize so rapidly that the fauna is in equilibrium with the prevailing environmental conditions. Colonization and community structure of aquatic insects vary among stable ponds, temporary ponds and lakes.