Search results
Results from the WOW.Com Content Network
The concept of the oceanic anoxic event (OAE) was first proposed in 1976 by Seymour Schlanger (1927–1990) and geologist Hugh Jenkyns [9] and arose from discoveries made by the Deep Sea Drilling Project (DSDP) in the Pacific Ocean. The finding of black, carbon-rich shales in Cretaceous sediments that had accumulated on submarine volcanic ...
After reducing some other minor elements, the bacteria will turn to reducing sulfate. This results in the byproduct of hydrogen sulfide (H 2 S), a chemical toxic to most biota and responsible for the characteristic "rotten egg" smell and dark black sediment color: [12] [13] 2 CH 2 O + SO 2− 4 → 2 HCO − 3 + H 2 S + chemical energy
Euxinic bodies of water are frequently strongly stratified; have an oxic, highly productive, thin surface layer; and have anoxic, sulfidic bottom water. The word "euxinia" is derived from the Greek name for the Black Sea (Εὔξεινος Πόντος (Euxeinos Pontos)) which translates to "hospitable sea". [1]
The oceans end up taking up chemicals, but also the small pieces of plastic that were not fully broken down. This causes dirty marine water and affects the ecosystems living in the oceans. [155] The incineration of plastic products pushes black carbon into the air. [156] Black carbon comes from emissions and is a lead contributor to climate ...
While marine pollution can be obvious, as with the marine debris shown above, it is often the pollutants that cannot be seen that cause most harm.. Marine pollution occurs when substances used or spread by humans, such as industrial, agricultural and residential waste, particles, noise, excess carbon dioxide or invasive organisms enter the ocean and cause harmful effects there.
Category 3 Water - Known as "black water" and is grossly unsanitary. This water contains unsanitary agents, harmful bacteria and fungi , causing severe discomfort or sickness. Type 3 category are contaminated water sources that affect the indoor environment.
The release of nitrogen oxides (N 2 O, NO) from anthropogenic activities and oxygen-depleted zones causes stratospheric ozone depletion leading to higher UVB exposition, which produces the damage of marine life, acid rain and ocean warming. Ocean warming causes water stratification, deoxygenation, and the formation of dead zones.
With primary causes being warming ocean waters, ocean acidity, and pollution. [3] In 2008, a worldwide study estimated that 19% of the existing area of coral reefs had already been lost. [ 4 ] Only 46% of the world's reefs could be currently regarded as in good health [ 4 ] and about 60% of the world's reefs may be at risk due to destructive ...