Unit 2 APES

Point source

a single, identifiable source of a pollutant, such as a smokestack or waste discharge pipe

Nonpoint sources

diffused and can therefore be difficult to identify, such as pesticide spraying or urban runoff

Outside of the optimum range what do organisms experience

physiological stress, limited growth, reduced  reproduction, and in extreme cases, death

How do coral reefs suffer

 increasing ocean temperature, sediment runoff, and destructive fishing practices

How do oil spills affect aquatic ecosystems

cause organisms to die from the hydrocarbons in oil. Oil that floats on the surface of water can coat the feathers of birds and fur of marine mammals. Some components of oil sink to the ocean floor, killing some bottom-dwelling organisms

What happens if oil washes up on a beach

it can have economic consequences on the fishing and tourism industries

What are ocean dead zones

areas of low oxygen in the world’s oceans caused by  increased nutrient pollution

What’s an oxygen sag curve

a plot of dissolved oxygen levels versus the distance from a source of pollution, usually excess nutrients and biological refuse

What can happen with using heavy metals in the industry

it can reach the groundwater, impacting the drinking water supply

What happens when litter reaches aquatic ecosystems

besides being unsightly, can create intestinal blockage and choking hazards for wildlife and introduce toxic substances to the food chain

What happens when there is increased sediment in waterways

can reduce light infiltration, which can affect primary producers and visual predators, it can also settle, disrupting habitats

What happens when elemental sources of mercury enter an aquatic ecosystem

bacteria in the water convert it to highly toxic methylmercury

What are endocrine disruptors

chemicals that can interfere with the endocrine system of animals

What are the effects of endocrine disruptors

can lead to birth defects, developmental disorders, and gender imbalances in fish and other species

When does Eutrophication occur

when a body of water is enriched in nutrients

What does the increase of nutrients in entropic aquatic environments do

causes an algal bloom

What happens when the algal bloom dies

microbes digest the algae, along with the oxygen in the water, leading to a decrease in the dissolved oxygen levels in the water

What does the lack of dissolved oxygen result in

large die-offs of fish and other aquatic organisms

What are hypoxic waterways

bodies of water that are low in dissolved oxygen

What are oligotrophic waterways

very low amounts of nutrients, stable algae populations, and high dissolved oxygen