Week 8 Biosphere Integrity

Question 1

What are the control variables and planetary boundaries for biosphere integrity?

Answer 1

Control variable: Extinction rate, genetic diversity

Planetary boundary : < 10 extinctions per million species

We have passed this or nearing

Question 2

How is life in the biosphere organized?

Answer 2

Biosphere - the total area on Earth where living things are found

Biome
Ecosystem
Community
population
individuaal

Question 3

What is a biome?

Answer 3

a portion of the biosphere by a distinct climate and particular assemblage of plants and animals adapted to it.

Question 4

What is a community?

Answer 4

all the populations living and interacting in an area. communities represent the “living’ portion of the ecosystem.

Question 5

what is an ecosystem?

Answer 5

an integrated system defined by its biotic and abiotic environmental conditions and their interactions all functioning as a unit.

nesting within each other

Question 6

What are ecosystem functions?

Answer 6

• the flow of energy and nutrients

-species interactions

-how species use resources and interact with habitat.

Question 7

Ecosystem services include:

Answer 7

1. provisioning
   -providing fuel and food
2. regulating
   -climate
   -flood control
3. support
   -nutrient cycling
   -carbon storage
4. cultural
   -recreation
   -cultural benefits

Question 8

What ecosystem services does stanley park provide?

Answer 8

-Recreation
-provides oxygen
-carbon storage
-temperature
-flood control
-cultural significance

Question 9

How does the biosphere function?

Answer 9

two fundamental processes:
1. energy flow
2.nutrient/biogeochem cycling

Question 10

What is the principle source of energy that drives ecological productivity (via photosynthesis?

Answer 10

Solar radiation
-autotrophs capable of photosynthesis and can feed themselves
-heterotrophs must feed on biomass produced by other organisms

Question 11

What are the trophic levels in the food web?

Answer 11

1. Quaternary producers
   feed at the apex of the food web
2. tertiary producers
   - feed on herbivores
3. secondary producers
   -feed on plants
4. primary producers
   -plants and photosynthetic bacteria

Question 12

What do decomposers and detritivores do?

Answer 12

Feed on dead matter from every trophic level.
perform essential service of recycling matter - returning nutrients back to the soil or water.

Question 13

What is an apex predator?

Answer 13

top-level predator with no natural predator of their own; resides at the top of the food chain

Question 14

Define habitat

Answer 14

the physical environment where a species lives

Question 15

Define niche

Answer 15

Role a species plays in its ecosystem, including habitat requirements and interactions.

Question 16

Define keystone species

Answer 16

a species that has a large effect on its environment compared to its abundance

when a keystone species is removed, the ecosystem may change drastically, even if the species removed was a small part of the ecosystem.

Question 17

What is a trophic cascade? Example

Answer 17

the impact of a predator on its prey affects one or more trophic levels

-when the apex predator is removed, can affect every layer below

-MUST occur across minimum of three trophic levels
-can also happen bottom up, removing producer

Removing sea otters from the chain, causes bloom of sea urchin since there is no one to eat them. decrease in kelp, not enough food to sustain the population.

Question 18

Every piece of an ecosystem is _______

Answer 18

interdependent

Question 19

The best way for an ecosystem to be resilient?

Answer 19

Biodiversity:
-the degree of variation in life
-affects ecosystem function and ecosystem services.

Question 20

Biodiversity contains?

Answer 20

Genetic diversity
Species diversity
Ecological diversity

Question 21

What are the Strategic Goals of the Aichi Biodiversity targets?

Answer 21

Goal 1: address the underlying causes of biodiversity loss by mainstreaming biodiversity across government and society.

Goal 2: reduce the direct pressures on biodiversity and promote sustainable use

Goal 3: improve the status of biodiversity by safeguarding ecosystems, species, and genetic diversity.

Goal 4: enhance the benefits to all from biodiversity and ecosystem services.

Goal 5: enhance implementation through participatory planning, knowledge management and capacity building.

Question 22

How is a ‘mass extinction’ defined, and what evidence suggests a 6th mass extinction due to human activities?

Answer 22

Mass Extinction: Defined by a significant loss of species disrupting entire ecosystems.

Evidence for the 6th mass extinction suggests that human activities are causing >10 extinctions per million species per year.