Method: Six species of seagrass belonging to the genera Syringodium, Cymodocea and Halodule were collected from their native habitat. The L-chiro-inositol content of the crude aqueous extracts prepared from different batches of Cymodocea nodosa flotsam was measured by quantitative H-NMR spectroscopy. High concentrations were found with values ranging from 22.2 to 35.0 mg.g plant dw. The presenc...

The present study determined and compared contents of macro- (Nitrogen-N, Phosphorus-P, Potassium-K, Calcium-Ca, Magnesium-Mg) and micro- (Zinc-Zn, Iron-Fe, Manganese-Mn, Cupper-Cu) nutrients in four seagrass species big-leaved (BL) Halophila ovalis (R. Br.) Hook. f., small-leaved (SL) H. ovalis (R. Br.) Ascherson, H. spinulosa (R. Br.) Aschers. in Neumayer and Halodule uninervis (Forssk.) Asch...

Seagrasses around the world are threatened by human activities that degrade water quality and reduce light availability. In this study, light requirements were determined for four common and abundant seagrasses along the Gulf coast of peninsular Florida using a threshold detecting algorithm. Light requirements ranged from 8% to 10% of surface irradiance for Halophila engelmannii to 25-27% of su...

A survey of leaf soluble amino acids was conducted for four subtropical seagrasses grown at several salinities. Proline functioned as an organic osmoticum in Halodule wrightii Aschers., Thallasia testudinum Banks ex Koenig, and Ruppia maritima L., while alanine functioned in an osmoregulatory capacity in Halophila engelmanni Aschers. When light-and salinity-induced variations in leaf NH(4) and ...

Inhibition of photosynthesis by ultraviolet-A radiation (UV-A, 315-380 nanometers) was examined in three marine angiosperms: Halophila engelmannii Aschers, Halodule wrightii Aschers, and Syringodium filiforme Kütz. Sensitivity to UV-A and photosensitization to UV-A by photosynthetically active radiation (PAR, 380-700 nanometers) were characterized.Net photosynthesis by Halodule and Syringodium ...

Nitrogen fixation (acetylene reduction) associated with roots of the seagrass Halodule wrightii was measured offshore near Beaufort and Moorhead City, N.C. Rates of acetylene reduction were higher in aerobic than in anaerobic assays and were linear for up to 5 days. The temperature range for acetylene reduction was 15 to 35 degrees C with a maximum activity at 35 degrees C. Nitrogenase activity...

BACKGROUND Seagrass species in the tropics occur in multispecies meadows. How these meadows are maintained through species co-existence and what their ecological drivers may be has been an overarching question in seagrass biogeography. In this study, we quantify the spatial structure of four co-existing species and infer potential ecological processes from these structures. METHODS AND RESULT...

Ramsar site designation is an acknowledgment of a wetland’s importance. In this study, we conducted biodiversity survey around Natuna to examine its eligibility as the next in Indonesia. This was through sampling for biological resources, using either transect, trapping, or visual observation. We surveyed 32 stations endangered and vulnerable fish, water birds, wetland-dependent species. Sample...