Macrophytobenthos biomass in the Northwestern Cuban shelf, almost 50 years ago

Abstract

Abstract This study presents for the first time a comprehensive review of the macrophytobenthos on the Northwestern Cuban shelf using data collected almost 50 years ago, and can be considered as a baseline for present and future studies. During 1972−1973 the total estimated fresh biomass was 1.88 million tons (686 tons km−2). Compared with seagrasses, seaweeds were 1.40 times more frequent but had a total biomass 2.86 times smaller. Frequency wise, 90 % of all seaweeds were Chlorophyta, while Phaeophyta, and Rhodophyta were 5 % each. Six Bryopsidales genera (Avrainvillea, Caulerpa, Halimeda, Penicillus, Rhipocephalus, and Udotea) comprised 73 % of 16 Chlorophyta species collected, and 80 % of their total fresh biomass. Turtle grass (Thalassia testudinum) leaves fresh weight was 96 % of all seagrasses biomass, and 71 % of the total macrophytobenthos biomass. The combined biomass of five Halimeda species and that of turtle grass leaves were 88 % of the total regional macrophytobenthos fresh biomass. Species presence was greatest on sand substrate, and least on reef rubble, with a total biomass greater at 1 m depth on organic mud mixed with sand. Of all species, only Halimeda spp. showed seasonal changes in biomass. The total biomass of macrophytobenthos was higher in the western larger and deeper Gulf of Guanahacabibes than in the eastern smaller and shallower Buenavista cays to La Mulata Port section of the shelf. The total macrophytobenthos biomass and that of some species showed significant correlations with depth. The eight most frequent macrophytes in the Northwestern Cuba shelf had similar Caribbean presence.