This study observed the spatial and temporal distributions of molluscs in a Halodule wrightii meadow, verifying if they respond satisfactorily to seasonal changes in this seagrass ecosystem. Twenty-four species were identified. Chitons were rare, bivalves had greater number of species (11), followed by gastropods (9) which were also the most abundant class (73%). All classes were more abundant ...

An early concern in the planning of the Space Shuttle Program was the loss of at­ mospheric ozone due to repeated Shuttle flights and a resultant increase in penetrant ultraviolet radiation. Our research group has examined the effects of an increase in this radiation (UV-B, 290315 nm) on three marine angiosperms (Halophila engelmannii Aschers, Halodule wrightii Aschers, and Syringodium filiform...

Mean flow and turbulence measurements collected in a shallow Halodule wrightii shoal grass fringe highlighted significant heterogeneity hydrodynamic effects over relatively small spatial scales. Experiments were conducted within the vegetation canopy (~4 cm above bottom) for sparse (40% cover) dense (70% vegetation, with reference near bed bare sediment. Significant benthic velocity shear was o...

Primary production rates of 4 autotrophic components in Halodule wrightii Aschers. beds off Horn Island in Mississippi Sound (USA) were measured over an annual cycle. Hourly production rates varied from as little as 0.9 mg C m-' for H, wrightii leaves in winter to as high as 1143 mg C m-' for eplphytic algae during summer. Stepwise multiple regression showed that only 15 % of the variation in h...