Ant Diversity in Forest and Traditional Hill-Tribe Agricultural Types in Northern Thailand

Abstract

This study investigated the impacts of traditional hill-tribe agricultural systems on biodiversity conservation. It compared the abundance and diversity of ants across a gradient of different types of land use in northern Thailand: tropical montane forest (MF); jungle converted to tea plantation (JT); ex forest left fallow for one year (F1); ex forest left fallow for eight years (F8 - the traditional hill-tribe agricultural system); and permanent agriculture (C -growing cabbages as an annual crop). Ants were collected from the uppermost 20 cm of the ground, covering the soil to the upper litter in eight 30 cm² quadrats from the different types of land use during a range of seasons at each site. A total of 12,006 ants were collected, representing 130 species from 48 genera in seven subfamilies. JT had the highest average number of species followed by MF, F8, F1 and C, respectively. There were significant differences in the number of ant species among types of land use and seasons, but no significant difference in the abundance of ants was found among land use systems. The results indicated that jungle tea land use maintained a significantly greater species-richness than any of the forest-fallow or annual-crop land uses in the highlands.