Where does pollution originate?
The bulk of contaminants that end up in the ocean are caused by human activity near coasts and far inland.
Nonpoint source pollution, which arises as a result of runoff, is one of the most significant forms of pollution. Nonpoint source contamination can occur from a variety of sources, including septic tanks, cars, farms, cattle ranches, and forestry harvesting regions.
Point source pollution refers to pollution that originates from a single source, such as an oil or chemical spill. Point source contamination events can have significant consequences, but luckily, they are less common. Point source contamination also includes discharge from malfunctioning or damaged facilities or water treatment systems.
Nutrients and algal blooms: Are there such a thing as too much of a good thing?
It is sometimes the concentration of a chemical rather than its nature that defines whether it is a pollutant.
Nitrogen and phosphorus, for example, are necessary components for plant development. However, if they become too plentiful in a body of water, they can cause an excess of algae, resulting in an occurrence known as an algal bloom.
Harmful algal blooms (HABs), sometimes known as "red tides," develop quickly and have devastating consequences on marine life and, in some cases, people. Excess nutrients entering a body of water, whether from natural or anthropogenic sources, can also cause hypoxia or dead zones.Large concentrations of algae sink and degrade in the water, using oxygen and depleting the quantity available to healthy marine life. Many marine creatures that reside in these places either perish or flee the area if they are mobile (such as fish).
How does marine debris affect the ocean?
Marine debris is a continuous environmental issue that affects the whole ocean and the Great Lakes.
Our oceans and streams are plagued by a diverse range of marine trash, from minuscule microplastics less than 5 mm in size to abandoned fishing gear and vessels.Dozens of marine species have been harmed by marine debris, which may damage or kill an animal if it is ingested or becomes entangled, and can jeopardize the environments on which they rely. Marine debris can also impede navigation safety and even endanger human health.
The bulk of marine debris originates on land and enters the ocean and Great Lakes via littering, inadequate waste management practices, storm water discharge, and catastrophic natural disasters such as tsunamis and hurricanes. Some detritus, such as abandoned fishing gear, can also be found in the water.This abandoned or lost gear is a significant issue since it can continue to trap and kill species, harm delicate ecosystems, and even compete with and destroy current fishing gear.
What are garbage patches and where can you find them?
Garbage patches are vast regions of the ocean that accumulate garbage, fishing gear, and other marine detritus.
The word "garbage patch" is a deceptive appellation, causing many people to imagine that garbage patches are "islands of litter" visible from a distance. These regions are really made up of various sizes of garbage, ranging from microplastics to enormous bundles of abandoned fishing gear.
These patches are generated by gyres, which are vast, rotating ocean currents that drag debris towards one spot, frequently the gyre's centre.
The ocean has five gyres: one in the Indian Ocean, two in the Atlantic Ocean, and two in the Pacific Ocean. Garbage patches of various sizes may be found in each gyre. Garbage patches are continually shifting in size and shape due to winds and currents. The trash that makes up the garbage patches may be found from the ocean's top all the way down to the ocean floor.
The consequences of marine contamination on seafood
Heavy metals and other pollutants can build up in seafood, making it unsafe to ingest. Microplastics can be consumed by fish and other aquatic creatures that filter their food.
Humans, whether they live near the beaches or far inland, are both a part of the issue and a part of the solution to ocean pollution. To help educators, students, families, and adults better grasp this worldwide issue, the Government Marine Debris Program provides a wealth of instructional tools.