Accumulation of heavy metals in the body and nest of ants in traditional oil mining geosite Wonocolo, Bojonegoro Geopark, East Java, Indonesia

Traditional oil mining in Wonocolo, Kedewan District, Bojonegoro Regency, East Java Province, Indonesia, causes soil contamination, also by heavy metals. On the basis of bioindicators, 63.3% of soil macrofauna are dominated by ants (Hymenoptera), which have the potential to be heavy metal bioaccumulators. This study aimed to analyze the types and amounts of heavy metal accumulation in the bodies and nests of ants found in Wonocolo. Samples were collected using exploration and hand shorting methods, while heavy metal accumulation was analyzed us ing XRF. The results showed that 13 types of ants collected accumulated heavy metals in their bodies and nests. Ten types of heavy metals were identified in the bodies of ants, with 3 of them found in all types of ants, namely Cu, Fe, and Zn. Thirteen types of heavy metals were also identified in the nests, with 6 of them found in all nests, namely Al, Fe, Mn, Sr, Ti, and Zn. On the basis of the number of metal type of accumulated, four types of ants have the potential to be bioaccumulators, namely: Camponotus pennsylvanicus, Tetramorium bicarinatum, Solenopsis invicta, and Cerebara colobobsis. The detection of various types of heavy metals in the bodies and nests of ants in the Wonocolo traditional oil mining area suggest that the ants in this area can potentially act as heavy metal bioac cumulators that can help the remediation process of soil contaminated by traditional oil mining activities.