31- threats to biodiversity 2,3,4

Question 1

some reasons why species are negatively affected by fragmentation

Answer 1

may need to be able to travel large areas to eat/mate

collisions with vehicles

Question 2

forest edge abiotic factors:

Answer 2

-more light
-dryer soil
-higher wind spread
-higher temp

Question 3

forest edge biotic factors:

Answer 3

-altered plant community
-altered dispersal of plants
-increase in invasive plants
-increase in competition
-decrease in suitable food sources

Question 4

hoe can we decrease habitat loss and fragmentation?

Answer 4

environmental impact assessments

protection of large, intact area

connection of habitat fragments

Question 5

what percent does overharvesting account for recorded threats of biodiversity?

Answer 5

18%

Question 6

what are the 4 threats to biodiversity?

Answer 6

1. change in land and sea use
2. species overexploitation
3. invasive species and disease
4. pollution

Question 7

what % does invasive species account for of threats to biodiveristy?

Answer 7

11-14%

Question 8

what percent does pollution account for threats to biodiversity

Answer 8

2-11%

Question 9

what percent is climate change for threats to biodiveristy

Answer 9

4-13%

Question 10

three categories of keystone species

Answer 10

predators - keep populations balanced

ecosystem engineers- activities have a positive effect on other species (prairie dog hills)

mutualists - form import relationships (pollinators)

Question 11

what are foundation species

Answer 11

build up the structure of an ecosystem - provide habitat (trees)

Question 12

two components of ecosystem stability

Answer 12

1. ability for the ecosystem to remain unchanged when disturbed
2. ability and rate of an ecosystem to recover from a disturbance