Physical and chemical water condition in and around the area of seaweed “Lahe” (Caulerpa Sp.) growth

Abstract

Lahe (local name of Sangihe) is the type of seaweed Caulerpa Sp, can be classified as green seaweed. Lahe grows naturally in the coastal waters of Batunderang Island and other areas in Sangihe Regency. Until about 40years ago, lahe was consumed by the Sangihe community. Formerly lahe was traded in several traditional markets. At present, the community only knows lahe through the Sangihe culinary exhibition. Our team conducts research on the potential and optimization of lahe as a functional food ingredient and medicine. The initial stage of the study was to measure, analyze and evaluate the physical and the chemical condition of the waters where lahe grows in the waters of the village of Batunderang. This article describes the physical and chemical condition of water. Analysis of physical and chemical condition of water can explain the ecological conditions that guarantee the growth of lahe, and its relation to productivity. The results of the analysis of physical and chemical conditions can also be used as references for ecological monitoring and lahe cultivation. Measurements are made in five positions that are determined based on ecological conditions variation. At each position, measurements were taken on four depth variations: 15 cm, 50 cm, 100 cm, and 200 cm below the surface. Measurements are carried out on the full moon, where the tide fluctuation is maximum. From the measurement data, we describe daily changes of: direction and velocity of currents, temperature of sea water and the temperature of air above the sea surface