Comparison of species diversity and abundance of ants in grassland and reforestation area at Lai Nan sub district, Wiang Sa district, Nan province

Grassland is a community with specific composition of living organisms. Nowadays, grasslands are used extensively by human activities that cause various effects on living organisms. This research were to investigate and compare the diversity and abundance of ants between in grassland and reforestation area at Lai Nan Sub-district, Wiang Sa district, Nan province. Six sampling methods: hand capture with constant time, sugar baiting trap, protein baiting trap, pitfall trap, leaf litter sifting, and soil sifting, were conducted monthly in the two study areas from June 2010 to June 2011. The overall species richness of ants was 34 species (23 species and 11 morpho-species) from 22 genera in six subfamilies. The Shannon Weiner species diversity index indicated that the diversity was higher in reforestation area (0.65) than in grassland (0.62). The diversity of ants werenot different between the two study areas from the high Sorensen’s similarity coefficient (92%). Besides different habitats, the environmental fluctuations due to seasonal factors also affected the variation of ants. The Sorensen’s similarity coefficient between wet and dry seasons in two study areas among seasons were 84-91%. The pattern of ant diversity showed that the two study areas were not different between the habitat and season. The first four highest abundant ants, three species were significantly correlated with some physical factors in two study areas. Afterwards, all collected ants were classified into six functional groups as Dominant Dolichoderinae, SubordinatCamponotini, Climate Specialists, Cryptic Specialists, Generalized Myrmicinae, and Specialists Predators. Both Climate Specialist and Cryptic Specialists were dominated in reforestation areabut not in grassland. Accordingly, ants could be used as indicators for monitoring changes of the disturbance habitat as well.