Factors Affecting the Distribution, Biomass, and Life Stages of Sargassum spp. in the Northwest Arabian Gulf

Abstract

The developmental stages of Sargassum along with physicochemical factors affect the Sargassum biomass and, thus, affect the size of the habitat used by various fauna and flora. In this study, Sargassum spp. were collected from four stations in Kuwait coastal waters that are mainly distinguished by their levels of turbidity. Investigations revealed that the effects of season (i.e., temperature and sunlight) and turbidity on differences in Sargassum biomass were significant (chi-square = 6.1, degrees of freedom (df) = 2, p = 0.048), but the effects of Sargassum species (chi-square = 5.4, df = 2, p = 0.067) and their life stages (chi-square = 6.73, df = 4, p = 0.15) on Sargassum biomass were not significant. The lack of significant effects of Sargassum spp. on biomass could be because the majority of the collected Sargassum are of one species, S. angustifolium. As for the effect of life stages on Sargassum biomass, this could be because the majority of the stages encountered are juveniles or spent, which are found almost equally among all species. These stages were encountered particularly in spring and summer, mainly at the medium- and low-turbidity stations. The distribution of Sargassum spp. showed strong localization, in which the species inhabiting high-turbidity stations were different from those inhabiting clear waters. This study revealed that the effects of season and turbidity on Sargassum spp. and their life stages on Sargassum biomass represent a reference point for further monitoring studies in northwestern Arabian Gulf.