Biodiversity and spatial distribution patterns of ant species in Chongqing City tea gardens

In order to select tea pest predatory ants in Chongqing tea gardens, a sample-plot survey method was used to study the biodiversity and spatial distribution patterns of ant species in tea gardens in the main tea-growing areas of Chongqing (altitude from 371 to 1 068 m). A total of 3 vertical bands were investigated. Three horizontal bands were designed along the above 3 vertical bands at three altitude ranks of 300 500 m, 500 700 m and 700 1 100 m. A total of 39 species, belonging to 4 subfamilies of Formicidae were identified in tea gardens in the main tea-growing areas of Chongqing. In different altitude tea gardens in the main tea-growing areas of Chongqing, the amounts of dominant ant species, common species, rare species and species richness of ant communities were 1 3, 1 6, 5 17 and 7 13, respectively. The Shannon-Wiener diversity, Pielou evenness and Simpson dominance indexes were in the ranges of 0.55 1.25, 0.08 0.16 and 0.26 0.65, respectively. In the same horizontal band, the Simpson dominance of Yongchuan-Rongchang vertical band was the minimum. The Banan-Nanchuan vertical band had the highest Simpson dominance index. The indexes of biodiversity were not significantly different among the different horizontal bands, which suggested that ant community biodiversities were on the same level. In contrast to a similar research in forest environment, ant species biodiversity was least in tea gardens in the main tea-growing areas of Chongqing. The range of the Jaccard indexes of community similarity was 0.22 0.48 and most communities had medium Jaccard index, moderately dissimilar in the tea gardens. In main tea-growing areas of Chongqing, 7 dominant species e.g. Tetramorium caespitum (Linnaeus) were found. Seventeen ant species had widened vertical distribution range, with activity range including canopy, ground and underground. They were potential resources of natural enemy insects of tea plant pests existed. With respect to ant species distribution, only 9 ant species were noted in the range of low to high altitude tea gardens. About 17 ant species were distributed in a vertical band. On the basis of the above analysis, the results showed that inter-community communication of ants was hindered by fragmented tea garden habitats both in the vertical and horizontal directions. The fragmented tea garden habitats were not good for ant biodiversity growth and stability in tea gardens in the main tea-growing areas of Chongqing.