Radioactive Cabon emissions from 20th Centuary bomb tests has reached the deepest parts of the ocean, according to the new research in AGU's journal Geophysical Research Letters.
Organisms at the ocean surface have incorporated this "bomb carbon" into the molecules that structure their bodies since the late Fifties. These organisms are then engulfed by Crustaceans in the deep ocean trenches. The conclusion of the studies show human pollution can quickly enter the food cycle and funnel it's way down to the deep ocean.
There's a terribly fundamental interaction between the surface and also the bottom, in terms of life systems, and human activities will have an effect on the biosystems even right down to eleven,000 meters, therefore we'd like to use caution concerning our future behaviours, same Weidong Sun, a geochemist at the Chinese Academy of Sciences in Qingdao, China, and author of the new study. it isn't expected, however it's graspable, as a result of it's controlled by the organic phenomenon.
"There's a very strong interaction between the surface and the bottom, in terms of biologic systems, and human activities can affect the biosystems even down to 11,000 meters, so we need to be careful about our future behaviors...It's not expected, but it's understandable, because it's controlled by the food chain." states Co-author of the new study, Weidong Sun.
Despite having extremely slow metabolisms, the crustaceans they studied unexpectedly live a very long time. This leads the authors of the study to suspect may be an adaptation to living in this impoverished and harsh environment.
The new studies has help scientists to understand how deep ocean creatures adapted to the impoverished environment. Authors suspect the reason why crustaceans unexpectedly live a very long time despite having a slow metabolism, was due to the adaptation to the extreme living conditions.
Creating radioactive particles
Carbon-14, or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons. It's created naturally once cosmic rays interact with nitrogen in the atmosphere.
Because carbon-14 decays at this constant rate, an estimate of the date at which an organism died can be made by measuring the amount of its residual radiocarbon. The carbon-14 method was developed by the American physicist Willard F. Libby about 1946.
During the 1950s and 1960s, Thermonuclear weapons test were conducted contributing in doubling Carbon-14 in the atmosphere. The levels of "Bomb Carbon" Peaked in the mid-1960s. As the nuclear test stopped, the bomb carbon quickly fell out of the atmosphere and mixed into the ocean surface. Since then, scientists have seen elevated levels of carbon-14 in marine organisms.
Adapting to the deep ocean atmosphere
Researchers discovered amphipods living in these trenches live longer and grow larger than those whom live in shallower waters. Typically, an Amphipods usually live less than 2 years and grow around 0.8 inches. However, the amphipods that lives in deep trenches are 10 years recent and can grow up to 3.6 inches long
The authors suspect that this is the byproducts of their evolution to living in a high pressure environment with limited of food supply. Due to the slow metabolisms and low cell turnover, this allows the amphipods to store energy for longer periods of time. The long life time also suggests pollutants can bioaccumulate in these unusual organisms.
"Besides the fact that material mostly comes from the surface, the age-related bioaccumulation also increases these pollutant concentrations, bringing more threat to these most remote ecosystems," Wang said