Vertical Distribution of Dissolved Oxygen Concentration at The Sea Pearl Cultivation Development Site, West Lombok, Nusa Tenggara Barat

Titrimetric method or Winkler Methode was applied to determine dissolved oxygen (DO) in sea waters of The Sea Pearl Cultivation Developement Site, West Lombok during southeast monsoon of June 2021. The samples were taken in three (3) different location (Gili Gede, Gili Genting and Autorei) of the cultivation site at Sekotong waters, West Lombok, Nusa Tenggara Barat. Measurement results of physical parameters at those locations were characterized with salinity was ranging at 31.9 - 32.3 PSU, temperature was ranging at 28.4 – 29.7 0 C. The concentration of dissolved oxygen measured by titration method is ranging from 3.4 - 5.2 mg / L. High oxygen content is found in the water column with a depth of 25 m or below the layer of the aquatic column where sea shell pearls are developed or cultivated. This condition indicates that the presence of cultivated sea shell pearls has utilized dissolved oxygen in the process of respiration and oxidation of organic matter. Dissolved oxygen becomes an important abiotic factor for ecosystems that support the sustainability of marine life and marine aquaculture development efforts.