HEAVY METALS ACCUMULATED BY PARAGYRACTIS SP. AND HYDROPSYCHE SP. IN KREO RIVER ADJACENT TO JATIBARANG LANDFILL, SEMARANG, INDONESIA

Benthic macroinvertebrates can accumulate pollutants such as heavy metals from water and sediment of a river. These studies aims to identify the differences in concentration of Cd, Zn, Cu, and Fe in Paragyractis sp. (Insecta: Lepidoptera) and Hydropsyche sp. (Insecta: Trichoptera) that live in Kreo River, before and after the Jatibarang landfill leachate discharge. Another aim was to find out the differences of these metals bioaccumulation factor of two benthic from its environment. To obtain the aims, benthic samples were collected at four stations on the Kreo River. The first station located next to ±150 m upstream from the point of discharge of leachate. The second, third, and fourth station respectively to be about 1, 500, and 3000 m downstream from the point. All the samples were analyzed by HACH DREL 2000 spectrophotometer in order to determine the total amounts of Cd, Zn, Cu, and Fe. Bioaccumulation factors (BAF) calculated based on the ratio between heavy metal content in benthic with the metals concentration from their environment. The results showed that the landfill leachate quite a role in increasing the concentrations of heavy metals (except Cu) in Hydropsyche sp., but did not cause increased in Paragyractis sp. Both benthic BAF showed a similar pattern based on the type of environment phase. Metals BAF of Hydropsyche sp. and Paragyractis sp. from water that is sorted from highest to lowest as follows: Cu > Zn > Fe > Cd, while the sediment is: Zn > Cu > Cd > Fe.