Damage to Ecosystems: Litter can smother coral reefs, seagrass beds, and other vital marine habitats, disrupting ecosystems and reducing biodiversity. It can also interfere with the natural behaviors and reproductive cycles of marine species.

How can fishing impact reef ecosystems and marine species?   Select ALL correct optionsFishing can create bycatch, killing non-target species like turtles.1Discarded nets, lines and hooks can entangle animals.2Taking organisms from the ocean does not harm marine species.3Fishing helps to keep the ocean clean by removing organic matter.

Propose ways that plastic pollution might decrease the biodiversity of a marine ecosystem.

How does animal agriculture impact the Great Barrier Reef? Select ALL correct optionsCarbon emissions that contribute to global warming increase, harming corals, e.g. bleaching.1Runoff can carry excess nutrients, causing algae to bloom and smother corals.2Animal agriculture has no effect on the Great Barrier Reef.3Land clearing can degrade soils, increasing runoff of sediment and animal waste.

For many years, scientists believed that runoff from commercial farms could cause excessive phytoplankton blooms. In 2005, Stanford University scientists were able to finally prove that theory. Now we have verified the information we need to better protect oceans from human pollution. How does this affect the ocean ecosystem and the human food chain? To answer that, we need to understand how humans interact with the ocean.The ocean ecosystem is more sensitive than it looks. We can see with the naked eye that plants and fish live in a delicate balance. Schools of fish move through the ocean in ways that do not put too much pressure on any one source of food. Different populations are kept in check by both the amount of food available and their predators. We must use scientific methods, however, to see that amounts of tiny molecules like nitrogen and oxygen also have a profound effect on ocean ecosystems.The ocean drives Earths water cycle. All but 3% of the water on Earth is in the ocean. It also strongly influences Earths climate, because much of the Suns heat is absorbed by the ocean. We get many resources from the ocean, such as tuna, shrimp, fish, crab, kelp, and blubber, among many others. The ocean influences all life on Earth. That is why it is very important that we are aware of how we affect ocean systems.Water that travels over the ground and drains into a stream, lake, river, or ocean is called runoff. Most runoff comes from rain, but pollution in the runoff often comes from water that has been used for agricultural purposes. This is water that has been used to irrigate the plants that farmers grow. Sometimes this water can collect contaminants from the ground as it rolls downhill. These contaminants can include lead, nitrogen, and phosphorus. Nitrogen is a chemical element that many farmers use to increase crop yields. It is the active ingredient in manure and many other plant fertilizers. Unfortunately, it has the same effect on ocean plants. This introduction of additional plant fertilizer into the ocean changes the balance of ocean plant growth. This can have serious consequences for ocean wildlife.Phytoplankton are microscopic algae that live in the ocean. Phytoplankton form the base of the aquatic food chain. Thousands of marine organisms rely on phytoplankton for food. Individually they are too small to be seen. They can be easily seen as a green color in the water when millions of phytoplankton are together. The chlorophyll in their bodies causes the green color. When phytoplankton quickly increase in numbers, these large concentrations of them are called algal blooms. Algal blooms have been happening naturally since man has been recording observations about the ocean. However, we have now begun to understand the relationship between contaminated runoff and ocean algal blooms.Algal blooms can cause hypoxic (low-oxygen) areas in waters. As the short-lived algae die, oxygen is taken from the water to help bacteria decompose their bodies. Hypoxic areas, or dead zones, are places where most oxygen dependent life forms cannot live. Dead zones can cause fish kills and other events where large numbers of marine organisms die.The scientists at Stanford University were the first to prove the connection between nitrogen in runoff water and algal blooms. They studied aerial photos of the Gulf of California. The land surrounding the Gulf of California is used heavily for agriculture. Hundreds of thousands of acres are used as farm land. Farmers fertilize these farms four times per year. They spray their crops with a nitrogen-based fertilizer. The fertilizer collects in the runoff and drains into the ocean. The researchers discovered that there was always an algal bloom within days of this fertilization cycle.Algal blooms can cause major problems for both aquatic life and commercial fisheries. It is important to understand how humans can causeand preventabnormally concentrated algal blooms.QUESTION 1Which is the most likely meaning for the phrase naked eyein paragraph 2?OPTIONSeyes without glasses eyes without magnifying devices eyes without clothes eyes without eyelashes

Explain why the death of corals is especially threatening to a reef ecosystem, even if it has high biodiversity.