Indian Ocean mean depth

The sea hare Dolabella auricularia (Aplysiidae) has been extensively investigated as a rich source of bioactive natural products, and a number of bioactive peptides and depsipeptides such as dolastatin 10 were isolated from both Western Indian Ocean specimens and Japanese specimens of this animal [for example, 134, 135]. This mollusk was also found to contain macrolide-type natural products. From D. auricularia, collected by hand at a depth of 0-1 m off the coast of the Shima Peninsula, Mie Prefecture, Japan, a 22-membered macrolide, dolabe-lide A (65), was isolated as a cytotoxin with an IC50 value of 6.3 pg/ml against HeLa-S3 cells. The gross structure of 65 was determined by spectroscopic analysis, and its absolute stereochemistry was elucidated by a combination of chemical means and the NMR spectroscopic method [136]. 

Riley, 1975). The 11 ions, except for iodine, compose more than 99.9% of salinity. Iodine is one of the most abundant micronutrients in seawater, with a total concentration of 5 X 10 to 6 X 10 g-l (0.4-0.5pM). Other micronutrients, such as nitrogen and phosphorus and many trace ions, are also contained therein. The three main oceans (i.e., the Atlantic, Indian, and Pacific oceans), including adjacent seas, occupy 70.8% of the earths surface (total sea area of 360.8 X 10 km ). Of the sea area, the ratio of the continental shelf (less than 200m deep), between 200 and 2000 m deep, and over 2000 m deep is 7.6, 8.5, and the remaining 83.9%, respectively. The total volume of seawater is 1.37 X 10 m (mean depth 3795 m) (Bowden, 1975). The ocean is thus a huge reservoir of iodine. 

The water property below the 3,500 m depth in the SCS is similar to that of the Philippine seawater in the layer from 1,900 m to 2,000 m, which shows that the bottom water in the SCS originates from the western Pacific. The same result could also be obtained from chemical tracer analysis. Using a box model, Han (1998) suggested the renewal time of the deep-water below 2,000 m is about 76 years. Fang and Wei (2002) pointed out that the circulation between Pacific Ocean and Indian Ocean through the SCS is a branch of the throughflow. From their numerical results, the annual mean transport is about (4 1.5) Sv, and the renewal time of the SCS water is (40 15) years. All the... 

Deuterium contents of seawaters from major oceans, rivers, lakes, and different water sources in North America and the Indian subcontinent have been surveyed. These studies show that water from the ocean depth has an average D-content of 156 1 ppm, with little variation, whereas the same for surface water is lower. D-content of tropical seawaters is around 160 1 ppm. Freshwater samples show large variations due to isotopic fractionation, which occur when water evaporates from land or sea and is condensed from air. Various factors such as local weather conditions, altitude, latitude, mean air temperature, drainage pattern, distance from the ocean, average precipitation, etc. are responsible for these variations. 

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