Search results
Results from the WOW.Com Content Network
Stable stratification of fluids occurs when each layer is less dense than the one below it. Unstable stratification is when each layer is denser than the one below it. Buoyancy forces tend to preserve stable stratification; the higher layers float on the lower ones. In unstable stratification, on the other hand, buoyancy forces cause convection ...
Denser water is below lighter water, representing a stable stratification. The pycnocline is the layer where the rate of change in density is largest. Ocean stratification is generally stable because warmer water is less dense than colder water, and most heating is from the sun, which directly affects only the surface layer.
A practical definition of water pollution is: "Water pollution is the addition of substances or energy forms that directly or indirectly alter the nature of the water body in such a manner that negatively affects its legitimate uses." [1]: 6 Water is typically referred to as polluted when it is impaired by anthropogenic contaminants.
For example, air and water; both are fluids and if we consider them together then they can be seen as a stratified fluid system. Density variations in the atmosphere profoundly affect the motion of water and air. Wave phenomena in air flow over the mountains and occurrence of smog are the examples of stratification effect in the atmosphere.
Most of the organisms involved are derived from the waste, wastewater or water stream itself or from the atmosphere or soil water. However some processes, especially those involved in removing very low concentrations of contaminants, may use engineered eco-systems created by the introduction of specific plants and sometimes animals.
In estuaries, for example, because freshwater flowing from a river into the sea is less dense than salt water, stratification in the water column can result. Vertical mixing between the water bodies is therefore reduced, restricting the supply of oxygen from the surface waters to the more saline bottom waters.
When the biological pollution is introduced to an aquatic environment, it contributes to water pollution. Biopollution may cause adverse effects at several levels of biological organization: an individual organism (internal pollution by parasites or pathogens), a population (by genetic change, i.e. hybridization of IAS with a native species),
The types of marine pollution can be grouped as pollution from marine debris, plastic pollution, including microplastics, ocean acidification, nutrient pollution, toxins and underwater noise. Plastic pollution in the ocean is a type of marine pollution by plastics , ranging in size from large original material such as bottles and bags, down to ...