Growth and Carrageenan Yield of Cultivated Kappaphycus alvarezii (Doty) in Deep Seawater Area of Saparua Bay, Central Maluku

Abstract

Cultivation of Kappaphycus alvarezii has been carried out by inverted pyramid method in the deep water of Saparua Bay. This study aims to analyze the daily growth rates (DGR), biomass productions (Y) and carrageenan yields (YC) of the green and brown strain of K. alvarezii with different water depth by inverted pyramid method in deep seawaters. K. alvarezii with an initial weight of 100 g were planted successively at the water depths of 1, 3, 5, 7 and 9 m during four growing seasons that last for 49 days in every season. The results showed that the highest daily growth rate and biomass production were on the green strain at the depth of 1 m and brown strain at the depth of 3 m, which were 4.18% and 749.29 g/m2 then 4.19% and 754.51 g/m2, respectively. Both of DGR and Y in brown strain was higher than the green strain at the surface layer. While the highest carrageenan yield were on the green and brown strain at the depth of 9 m, which were 16.53% and 14.85%, respectively. Seaweed cultivation in deep waters has a positive impact on carrageenan yields in line with the increasing depths while the growth rate and the biomass production can be achieved higher at the lower depth.