DINAMIKA Fe DAN Mn DI AREAL PERKEBUNAN KELAPA SAWIT DI LAHAN PASANG SURUT KABUPATEN BARITO KUALA, KALIMANTAN SELATAN

Abstract

This research was carried out in oil palm plantations on tidal land. Determination of the location of observation is done purposively. This study aims to study the dynamics of Fe and Mn based on changes in the pH value of a body of water as a result of clearing oil palm land on tidal land in Barito Kuala Regency South Kalimantan Province. Soil samples were taken from oil palm plantation land with a depth (0-60 cm) to study the physical and chemical properties of the soil. The soil is then dried by wind and prepared for laboratory analysis. The processed data comes from water quality data records recorded from the range of 2014 to 2018, especially for the parameters of pH, Fe, and Mn. The pH parameter is used as a reference to study changes in water quality in both the rainy and dry seasons, while the Fe and Mn parameters are used as observations of the solubility of metals from the soil. The results showed that the solubility of Fe and Mn in water was highly dependent on changes in pH. The tendency for high solubility to occur at Fe and Mn concentrations at low pH values and vice versa if the pH value increases. Iron solubility is closely related to the pyrite content in the soil through the oxidation process, causing a high Fe content accompanied by a decrease in pH as a result of the release of large amounts of H + ions into the water. While the Mn solubility will also be in the ground water system, manganese compounds change depending on the pH of the water. Changes in manganese compounds in nature based on pH conditions at valence two are generally soluble in water. Channel construction at the opening of oil palm plantations on tidal swamp land in Barito Kuala Regency, South Kalimantan has an impact on changes in pH and Fe and Mn content in the waters.