Diversity and Abundance of Insect Pollinators in Different Land Use Types in Jambi, Sumatra

Abstract

Indonesia is one of the tropical countries with high biodiversity. Recently, the biodiversity of plants and animals is declining due to forest converting to settlements, mines, agricultures, and plantations. In Central Sumatra including Jambi, annual deforestation rate reaches 3.2%-5.9%. Converting natural landscapes to agricultural land affects insects biodiversity, including insect pollinators. The research aimed to study diversity and abundance of insect pollinators in different land use types, i.e. oil palm plantation, rubber plantation, and jungle-rubber in Jambi, Sumatra. Observation and collection of insect pollinators were conducted from November until December 2012 at Bejubang, Batanghari regency, Jambi province. Insect observations were conducted in understory plants at three land use types, i.e. oil palm plantation, rubber plantation, and jungle-rubber. Scan sampling method was employed to explore the diversity and abundance of insect pollinators at 08.00-10.00 and 14.00-16.00 in sunny days. This study consist of found 1308 individuals of insect pollinators, belonging to 54 species,7 families, and 3 orders (Hymenoptera, Diptera, and Lepidoptera). Number of species and individual of insect pollinators found in oil palm plantation (43 species, 561 individuals) and rubber plantation (40 species, 650 individuals) were higher than jungle-rubber (7 species, 97 individiuals). Giant honey bee (Apis dorsata) and stingless bee (Trigona sp. (=aff. T. planifrons)) were abundant in oil palm plantation, while stingless bee (T. laeviceps) and small carpenter bee (Ceratina lieftincki) were abundant in rubber plantation. Whereas, hoverfly (Syrphidae sp5) was abundant in the jungle-rubber. The abundance and species richness of insect pollinators in the morning were higher than in the afternoon. Diversity and evenness of insect pollinators in oil palm and rubber plantations were higher than jungle-rubber. The abundant of flower of understory plants in oil palm and rubber plantations indicated insect pollinators forage in those locations. Meanwhile, jungle-rubber and rubber plantations were prefered by insect pollinators for nest building, because there were many large trees, branches, and broken twigs. The insect pollinators community in oil palm plantation and rubber plantation were more similar than in oil palm plantation and jungle-rubber, or in rubber plantation and jungle-rubber.