Distribution and Accumulation of Heavy Metals in Surface Sediment of Lake Junín National Reserve, Peru

The distribution and accumulation of heavy metals in the surface sediment of Lake Junin National Reserve was evaluated using the pollution factor (CF), pollution load index (PLI) and geoaccumulation index (Igeo), during 2018. Surface sediment samples were collected from 10 sampling sites, with three repetitions, during the rainy and dry seasons. The heavy metals determined were Fe, Cu, Cr, Cd, Pb and Zn; As, was also determined. The results revealed the descending order of Fe > Cu > Zn > As > Pb > Cd > Cr concentrations recorded in the three sampling sectors. The values of the CF obtained for the metals qualified as low CF, in times of rain and low water. The CF values of Cd were qualified as moderate contamination factors at all sampling sites, except at LJ1 where it qualified as CF considerable. The PLI for Lake Junin ranged from 0.0721 to 0.3260. The Igeo obtained indicated that the sampling sites are not contaminated by the heavy metals under study. Therefore, the mean values for heavy metals and As did not exceed the reference values and sediment quality guidelines. In general terms, CF, PLI and Igeo indicate that there is no appreciable contamination by these metals in Lake Junin; except for Cd.