Biogeochemical significance of fatty acid distribution in the coastal upwelling ecosystem off Concepción (36°S), Chile

► Fatty acids (FAs) in the upwelling ecosystem off Chile were studied. ► Seasonality was observed in FA abundance in surface water and sediments. ► Seasonal changes in FA composition were apparent in surface water. ► FA composition of bottom water and sediments did not change seasonally. ► FA composition was diagenetically altered during sinking.