National Institute of Oceanography, India

About: National Institute of Oceanography, India is a facility organization based out in Panjim, Goa, India. It is known for research contribution in the topics: Monsoon & Population. The organization has 4713 authors who have published 6927 publications receiving 174272 citations.

Bacterivory: a novel dual role for thraustochytrids in the sea

Abstract: Two thraustochytrids, Thraustochytrium striatum Schneider and Schizochytrium mangrovei Raghukumar, isolated in 1989 in axenic cultures using pine pollen in seawater from mangroves in Goa, India, were observed in continuous-flow chambers. When grown in the presence of bacteria, both species produced amoebae, which moved using pseudopodia and phagocytosed bacterial cells. Several amoebae were produced in ‘sporangia’, or isolated vegetative cells transformed directly into amoebae. These findings were confirmed with several single-cell isolations of the protists. The demonstration of phagotrophic amoebae in these organisms suggests a dual role for thraustochytrids in nature, namely a fungus-like breakdown of complex organic molecules as well as bacterivory. This phenomenon also places the thraustochytrics in a unique relationship with many other protistan groups.

Truth and consequences: the bioinvasion of the Mediterranean Sea.

Abstract: Over 660 alien marine multicellular species have been recorded in the Mediterranean Sea, with many establishing viable populations and subsequently dispersing from their points of entry. A brief overview is presented of the current state of knowledge of bioinvasions in the Mediterranean Sea, with particular attention paid to gelatinous invasive species. A database of alien species records was used to characterize their identity, pattern of expansion and native region, and to discuss the relative importance of different taxa and vectors in the various regions of the sea. The temporal and spatial spread of 4 alien scyphozoans and 2 alien ctenophores is outlined. Although thermophilic species constitute the majority of Mediterranean aliens, Erythrean aliens are predominant in the east, with shipping and mariculture being mainly responsible for introductions in the northwest. The propagule pressure driving the Erythrean invasion is powerful in the establishment and spread of alien species in the eastern Mediterranean. The implications of the enlargement of the Suez Canal, reflecting patterns in global trade and economy, are briefly discussed. Finally, as alien species inventories play a pivotal role in informing regional policy and management decisions and identifying resource priorities, the scientific community is called upon to pay particular attention to their accuracy and veracity.

Trace Metals in the Water Columns of the Red Sea and the Gulf of Aqaba, Egypt

Abstract: Seawater samples were collected from the northern Red Sea and the Gulf of Aqaba at different depths during February 1999 and analyzed for iron, zinc, manganese, nickel, copper, cadmium, cobalt and lead to determine the existing concentration of these metals, their distribution patterns and where contamination has occurred. The concentrations of Fe, Zn, Mn, Ni, Cu, Cd, Co, Pb were scatteredin the ranges: (0.56–4.44; mean 1.67±0.9 μg L-1), (0.13–1.17; mean 0.24±0.12 μg L-1), (0.06–0.21; mean 0.13±0.03 μg L-1), (0.05–0.52; mean 0.16±0.06 μg L-1), (0.07–0.29; mean 0.14±0.06 μg L-1), (0.02–0.78; mean 0.49±0.14 μg L-1), (0.06–0.29; mean 0.15±0.04 μg L-1), and (0.02–0.68; mean 0.31±0.13 μg L-1), respectively. The results revealed a small range of variation and regional irregularities. It also indicated significant higher concentrations for Fe, Cd and Pb compared to other metals. Compared to the northern Red Sea, significant higher concentrations for Ni and Cd are measured at the Gulf of Aqaba. Other metals, i.e. Fe, Zn, Mn, Cu, Co, and Pb are not significantly different in both areas indicating no distinct concentration gradients. Except for Pb, the distribution patterns indicated significantly lower concentrations at surface layer in both regions, then increasing to their maximum values at the sub-surface layers which followed by a decrease in deep water. The study indicated also that the mean concentrations of trace metals examined here are much lower than those reported for the Mediterranean Sea and typical of open ocean water.

Monthly-mean wind stress along the coast of the north Indian Ocean

Abstract: Monthly-mean wind stress and its longshore and offshore components have been computed using the bulk aerodynamic method for each of a string of 36 two-degree-latitude by two-degree-longitude squares along the coast of the north Indian Ocean. The data source for the computation is the sixty-year mean resultant winds of Hastenrath and Lamb. The main features exhibited by the components, taking the longshore components as positive (negative) when the Ekman transport is away from (towards) the coast, are: (1) Along the coasts of Somalia and Arabia, the magnitude of the wind stress is among the highest in the north Indian Ocean, and its direction is generally parallel to the coastline. This results in a longshore component which is large (as high as 2·5 dyne/cm2) and positive during the southwest monsoon, and weaker (less than 0·6 dyne/cm2) and negative during the northeast monsoon. (2) Though weak (less than 0·2 dyne/cm2) during the northeast monsoon, the monthly-mean longshore component along the west coast of India remains positive throughout the year. The magnitude of the offshore component during the southwest monsoon is much larger than that of the longshore component. (3) The behaviour of the wind stress components along the east coast of India is similar to that along the Somalia-Arabia coast, but the magnitudes are much smaller.