biodiversity

Question 1

what is meant by habitat?

Answer 1

the place where an organism lives

Question 2

what is meant by population?

Answer 2

organisms of the same species that live in a particular habitat at the same time

Question 3

what is meant by community?

Answer 3

all of the organisms of all the different species that live in a particular habitat at the same time

Question 4

what is biodiversity?

Answer 4

the variety of living organisms in an area

Question 5

what is species richness?

Answer 5

a measure of the number of different species in a community

Question 6

what is meant by index of diversity?

Answer 6

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

Question 7

what is the equation for calculating index of diversity? (don’t need to know formula but need to know how to use it)

Answer 7

N ( N-1 ) / sum of n (n-1)

where N= total number of organisms of all species

where n= total number of organisms of each species

Question 8

what does biodiversity reflect?

Answer 8

how well an ecosystem functions

the higher the species diversity index, the more stable an ecosystem usually is and the less it is affected by things such as climate change

Question 9

what is decreasing species diversity?

Answer 9

deforestation and agriculture

Question 10

what are agricultural ecosystems controlled by?

Answer 10

humans- some species are removed to allow for greater growth of another

any particular area can only support a certain amount of biomass so if most of an area is taken up by farmer’s desirable species, then many other species have to compete for what space is left

Question 11

what is used by farmer’s to remove species that provide competition for crop?

Answer 11

pesticides

Question 12

what is the result of farmer’s selecting species they want to grow for particular qualities that increase yield?

Answer 12

reduces number of species and genetic variability of the species

so gives ecosystem a low species diversity index

Question 13

why is loss of biodiversity the most serious consequence of deforestation?

Answer 13

deforestation makes land available for uses such as agriculture and housing

forests hold may habitats so these are destroyed

Question 14

give some examples of conservation techniques? (5)

Answer 14

-plant hedges rather than erect fences as field boundaries

-reduce use of pesticides- use biological control

-use organic rather than inorganic fertilisers

-leave wet corners of fields rather than draining them

-maintain existing ponds and create new ones