3.4.6 - biodiversity

Question 1

what is biodiversity?

Answer 1

the variety of living organisms in an area

Question 2

what is a habitat?

Answer 2

the place where an organism lives

Question 3

what is a community?

Answer 3

all the populations of different species in a habitat

Question 4

what are the two levels of biodiversity?

Answer 4

1. local biodiversity
2. global biodiversity

Question 5

what 2 ways can biodiversity be measured?

Answer 5

1. species richness
2. index of diversity

Question 6

what is species richness?

Answer 6

a measure of the number of different species in a community

Question 7

how can species richness be worked out?

Answer 7

by taking random samples of a community and counting the number of different species

Question 8

why is the index of diversity more accurate then species richness?

Answer 8

it is calculated using an equation that takes both the number of species in a community and the abundance of each species into account

Question 9

what is the index of diversity equation?

Answer 9

N(N-1)
d= ————-
sum of n(n-1)

N= total number of organisms of all species
n= total number of organisms of one species

Question 10

how does woodland clearance impact biodiversity?

Answer 10

-it is done to increase the area of farmland
-it directly reduces the number of trees and sometimes the number of different tree species
-it destroys habitats so some species could lose their shelter and food source
-species will die or forced to migrate to another area which reduces biodiversity

Question 11

how does hedgerow removal impact biodiversity?

Answer 11

-done to increase the area of farmland
-destroys habitats which kill organisms or forces them to migrate

Question 12

how do pesticides impact biodiversity?

Answer 12

-they are chemicals which kill organisms that feed on crops
-reduces biodiversity by directly killing pests
-any species that feed on the pests will lose a food source so their numbers could also decrease

Question 13

how do herbicides impact biodiversity?

Answer 13

-they kill unwanted plants
-reduces plant diversity and could reduce the number of organisms that feed on the weeds

Question 14

how does monoculture impact biodiversity?

Answer 14

-this is when farmers have fields containing one type of plant
-a single type of plant reduces biodiversity directly and will support fewer organisms as a food source

Question 15

what 5 agricultural factors impact biodiversity?

Answer 15

-woodland clearance’s
-hedgerow removal
-pesticides
-herbicides
-monocultures

Question 16

what are three examples of conservation schemes?

Answer 16

-giving legal protection to endangered species
-creating protected areas to restrict development
-the environmental stewardship scheme encourages farmers to conserve biodiversity

Question 17

what is local biodiversity?

Answer 17

the variety of different species living in a small habitat that is local to you

Question 18

what is global biodiversity?

Answer 18

the variety of species on earth

Question 19

what does an index of diversity describe?

Answer 19

the relationship between the number of species in a community and the number of individuals in each species