3.2 How Humans Influence Ecosystems

Question 1

What is a sustainable ecosystem?

Answer 1

An ecosystem that provides economic opportunities while maintaining biodiversity and ecosystem health for the future

Question 2

What is habitat expansion and how is an ecosystem affected by it?

Answer 2

• humans take over natural space for the creation of cites and agriculture
• habitats are destroyed and can no longer supports the species that lived there

Question 3

What is habitat fragmentation and how is an ecosystem affected by it?

Answer 3

• agriculture, roads, and cities divide natural ecosystems into smaller, isolated fragments
• plant pollination, seed dispersal, wildlife movement, and reproduction are adversely affected

Question 4

What is deforestation and how is an ecosystem affected by it?

Answer 4

• forests are logged or cleared for human use and never replanted
• the number of plants and animals living in an ecosystem are reduced

Question 5

What is soil degradation and how is an ecosystem affected by it?

Answer 5

• deforestation and land clearance leave land bare so water and wind erosion remove topsoil
• organic matter, water, and nutrients are removed along with the topsoil, reducing plant growth

Question 6

What is soil compaction and how is an ecosystem affected by it?

Answer 6

• agricultural farm vehicles and grazing animals squeeze soil particles together
• reduces the movement of air, water, and soil organisms in soil, hindering growth of plants and increasing run-off of fertilizer and pesticides

Question 7

What is contamination and how is an ecosystem affected by it?

Answer 7

• introduction of harmful chemicals or micro-organism into the environment
• toxins are introduced into the environment in harmful concentrations and kill plants and animals

Question 8

What is overexploitation and how is an ecosystem affected by it?

Answer 8

• a resource, like fish or forests, are used or extracted until depleted
• food web interactions are affected, organisms become less resistant to disease and less able to adapt to environmental change, extinction (the dying of of species) can occur

Question 9

What is the result of human expansion to ecosystems? (2)

Answer 9

• habitat fragmentation

- habitat loss

Question 10

How are the unique populations of plants, animals, and micro-organisms in aquatic ecosystems threatened by human resource use? (2)

Answer 10

• human expansion

- release of toxins far upstream (contamination)

Question 11

What are estuaries?

Answer 11

Coastal bodies of water where rivers or streams (freshwater) meet the ocean (salt water)

Question 12

What are phytoplankton and zooplankton? What are they affected by and why are they important?

Answer 12

• phytoplankton: plant-like micro-organisms
• zooplankton: animal-like micro-organisms
• affected and threatened by human expansion
• they are the basis of many aquatic ecosystem food chains

Question 13

What is topsoil and why is it important?

Answer 13

• the upper layer of soil

- it is where most of the nutrients, water, and air are found for plant growth

Question 14

What are some examples of resource exploitation? (3)

Answer 14

• harvesting fish and timber
• mining coal and minerals
• extracting oil and gas

Question 15

What do humans depend on resource exploitation for? (5)

Answer 15

• jobs
• materials
• food
• shelter
• energy

Question 16

What does resource exploitation lead to? (3)

Answer 16

• habitat loss
• soil degradation
• contamination of water supplies

Question 17

What is traditional ecological knowledge?

Answer 17

In Aboriginal culture, information about what past conditions were like and how ecosystems and humans interact, that is passed down from generation to generation in the form of stories, songs, cultural beliefs, rituals, community laws, and traditional practices

Question 18

What is the “Spring Burn” and what does it do?

Answer 18

• a tradition passed down from traditional ecological knowledge thats allows for ecological renewal by:
  
  • improving the growth of berries, which attracts more animals
  • recycles nutrients, creates more diversity, reduces forest litter, and opens the canopy to allow more sunlight to reach plants