Effect of industrial and residential sewage sludge and burnt garbage on cadmium content in soil and kangkong plants (Ipomoea reptans L Poir)

Abstract

This research aimed to determine the effect of sewage sludge from industry and residential and burnt garbage that applied to Inceptisol as media for kangkong (Ipomoea reptans L Poir). This study was using a randomized block design consisted of 2 factors. Factor 1 was the type of sewage sludge with 3 treatments, namely L1 = sludge in urban settlements, L2 = sludge from Mabar Industrial Area (KIM), and L3 = Burnt garbage from Medan, Sumatera Utara. Factor 2 was the dosage of sewage sludge with 3 treatments, namely D1 = 50%, D2 = 75% and D3 = 100% applied with 3 replications. The result showed that the application of sewage sludge taken from the industry, municipal, and burnt garbage increased the level of cadmium (Cd) in soil and kangkong plant. Moreover, the Cd content in soil with all types of sludge with a dosage level of 75% and 100% exceeded the critical limit of Cd in soil, which was 0.5 ppm. The concentration of Cd in plants was higher than in the soil, but under critical level for the plant, which was 5-10 ppm.