MEASUREMENT OF DIVERSITY INDICES OF TROPHIC GUILDS OF INSECTS ASSOCIATED WITH THE THORN FOREST COMMUNITY AT HARAPPA ARCHAEOLOGICAL SITE

Insects are dominant component of biodiversity in the terrestrial ecosystems which play important roles in mediating the relationship between the plants and various ecosystem. Shannon-Weaver diversity index, Simpson index, Hill diversity index and Sorenson similarity index were used to explain the diversity of various insect guilds of old groves and rehabilitated stands of the thorn forest community at Harappa. The resemblance in the insect trophic guilds-plant association was found by the cluster analysis. A total of 2419 insects belonging to 147 insect species representing various trophic guilds were present in old groves while a total of 1238 insects belonging to 85 insect species of various trophic guilds were present at restored site. Mean numbers of herbivore, predator and visitor insect species were significantly lower (p 0.05) at the restored site while pollinators, scavengers and pests showed no significant difference (p 0.05) between both sites. According to Shannon index, herbivores showed no significant difference in diversity among both sites as they showed 100% similarity while predators, pollinators, scavengers, visitors and pests showed significantly less diversity (p 0.05) at the restored site. Salvedora oleoides and Tamarix aphylla had similar trophic guild-plant associations according to the cluster analysis. Both the sites showed 72% similarity regarding various functional guilds so it is expected that with the increasing age and plant diversity of the restored community the diversity of insect guilds species will also increase.