Analysis of primary productivity levels based on chlorophyll-A concentrations in squid ( Uroteuthis sp.) fishing grounds of the Malacca

Abstract The Malacca Strait is a body of water located along the equator, making it influential in climate change processes that affect primary productivity through various factors. This study aims to determine the distribution of chlorophyll-a concentrations, sea surface temperature, and surface current velocity; compare chlorophyll-a concentrations at the surface and within the water column; and examine the relationship between chlorophyll-a concentrations and primary productivity in the Malacca Strait. Data were collected through direct field observations and satellite image processing using SeaDAS and ArcGIS software. The results showed that the distribution of chlorophyll-a from July to December ranged from 1.189 to 3.297 mg/m 3 , sea surface temperature ranged from 26.56 °C to 29.92 °C. The comparison of chlorophyll-a concentrations between the surface and the water column in the Malacca Strait was not significant, which was attributed to differences in sunlight penetration into the water. The relationship between chlorophyll-a and primary productivity in this study was positive (directly proportional) with a strong correlation. This research is expected to provide insights into primary productivity levels based on chlorophyll-a concentrations in marine waters using the Vertically Generalized Production Model (VGPM) method.