Accumulation of copper metal (Cu) on the plant Ipomoea carnea, Jacq in around the Limboto lake

Limboto Lake is one of the main lakes in the north part of Sulawesi island, Indonesia. This lake is categorized as a tectonic lake, which currently undergoing a serious degradation, due to many residences built in the area. Thus, the depth of the lake is quickly shrinking. A large quantity of poisonous kale (Ipomoea carnea L) grows in the around of the lake. This study aims at finding out the accumulation of copper (Cu) in the poisonous kale that grows in the around of the Limboto Lake. This study is a descriptive quantitative study using survey method with purposive sampling method in three observation sites, the estuary of the Alopohu river, the estuary of the Biyonga river, and the estuary of the Talubongo river. The variable being measured in this study is the level of Cu in the root, stem, and leaves, as well as the rhizosphere of the poisonous kale. The calculation of the Cu is carried out through Atomic Absorption Spectrophotometry (AAS). This research shows that the range of Cu accumulation in the root is (3.61-36.00 mg/L), stem (0-15.00 mg/L), leaves (0-42.94 mg/L) and in the rhizosphere of the plant is (0.12-26.00 mg/L). The poisonous kale plant can be utilized as the Cu accumulator. (paper)