Ecology and Global Change Flashcards

Flashcards to help review key concepts from the Ecology and Global Change lecture.

What two chapters are the main focus of this lecture?

Chapter 55: Ecosystem and Restoration Ecology and Chapter 56: Conservation Biology and Global Change

What is a food chain?

A linear picture of the flow of food from species to species.

What are the four trophic levels of a food chain?

Producer, primary consumer, secondary consumer, decomposers/detritivores

What is the role of a producer in a food chain?

Autotrophic organisms which make their own food, such as photosynthetic plants, algae, and bacteria.

Define primary consumer.

An organism which eats a plant for food, like a herbivore.

What is a secondary consumer?

An organism which consumes a primary consumer, like a carnivore.

What do decomposers/detritivores consume?

Detritus – non-living organic matter such as fallen leaves, feces, and dead organisms.

How do food webs differ from food chains?

Food webs show multiple predators per prey and multiple prey per predator, offering a more realistic view compared to linear food chains.

Define (gross) Primary Productivity.

Total light energy converted to chemical energy in a given period of time.

What is Net Primary Productivity?

Total primary productivity (gross) minus energy used by the producers themselves, often 50-85% of gross PP.

What percentage of energy is typically transferred from one trophic level to the next?

5-20%

Why is energy lost during transfer between trophic levels?

Organisms use energy for their own movements and activities, and much energy is lost to heat.

What is biological magnification?

A process where a toxin cannot be metabolized and accumulates in the tissues of exposed animals, increasing up the food chain.

Give an example of a substance that undergoes biological magnification.

DDT insecticide, Mercury

What were the effects of DDT?

DDT affected Bald Eagles, Peregrine Falcons, Whooping Cranes, Brown Pelicans, Osprey, etc.

What are some types of fish that have high levels of mercury?

Sharks, swordfish, Mackerel

What are safe fish to eat in regards to mercury levels?

Shrimp, light tuna, salmon, catfish

What is the greenhouse effect?

A normal feature of Earth’s atmosphere trapping solar energy by gases like H2O and CO2, which are transparent to visible light but opaque to infrared radiation.

What is the evidence that human activity is causing an increase of carbon dioxide?

Chemistry of burning hydrocarbons (coal, petroleum products, natural gas)

What is some evidence that shows the Earth has had a warming trend?

Direct measurement of temperature, Shrinking of tropical ice fields, Expansion of Sahara desert, Changes in sea level, Changes in polar ice

What is a potential effect of global warming?

Sea level rise, Increase in frequency of extreme weather events, Some species may not be able to migrate poleward and/or adapt quickly enough

What caused the Ozone depletion?

Chlorofluorocarbons from refrigerants and aerosol cans

Where was the hole in the ozone layer located?

Over the Antarctic/Australia/New Zealand/Chile/Argentina

What are the main causes of modern mass extinction?

Habitat destruction and fragmentation, Introduction of exotic species, Overexploitation, Disruption of interaction networks (e.g. loss of keystone species)

What is a possible solution to help avoid modern mass extinction?

Slowing and likely soon end of world population growth, Recognition of biodiversity hot spots, Zoned reserve concept of management, Wildlife corridors

Why is thermal expansion a concern?

Thermal expansion of the sea can cause sea level rise