Home About Us Advertise with Us Disclaimer FAQ's Contact Us
Posted on May 8, 2008 in Latest News
With the rapid warming up of oceans the condition of marine life is deteriorating. Most of the areas have been observed as oxygen depleted resulting, in sea deserts or dead zones. A considerable chunk of ecosystem and fishing zones has already been affected and the trend is still going on at an alarming rate.
Lothar Stramma conducted the research along with his group assembling records and studying the water world of past 50 yrs. Study reveals that in the past 50 yrs there has been expansion in hypoxic zones. The most prominent ones are the Eastern Tropical Atlantic and The Equatorial Pacific. The carbon and nitrogen cycles are also affected due to it. The level of oxygen is less then the critical oxygen level needed to support the marine habitat. The time line of oxygen concentration was studied at depths between 985 and 2295, keeping the records of past 50 yrs.
The depletion of oxygen in water is due to rise in temperature. The warm water looses its capacity to store oxygen. Pollution also contributes to hypoxia. The World Resource Institute has found 415 sites across the globe, these regions have observed to be over enriched with nitrogen and phosphorous. This eutrophication can prompt the development of algae that further depletes the oxygen in water. The result is oxygen deprived regions are unable to support marine organisms and other aquatic life.
This has triggered more suffocating zones due to these hypoxic waters. The deserts not only run vertically but horizontally as well. It is believed that the underwater desert is widening. The reason behind it is with the rise in temperature the warm oxygen rich surface water does not circulates to lower depths. The density of water reduces, as it gets warmer. The deeper and middle layers are most affected, as there is less supply of oxygen from the surface. The larger fishes and aquatic animals are at risk, as they require considerable amount of energy.
The low oxygen zones are increasing and they may shift towards the Continental shelf influencing areas of fishing. The biological productivity can get reduced severely hampering the food chain. It has been reported that the concentration levels of oxygen have gone down at the depth of 330 to 1310 feet between the yr 1956-2006.
The new study though highlights that the global warming could be a possible reason, but again it was noted that this phenomenon had occurred before also.
Records of the paleontological era have shown the ocean suffocation in the past. About 250 million yrs ago 90% of marine habitat was wiped out. But the fact remains that other factors are aggravating the global warming problem.
» Filed Under Latest News