Module 6.6

Question 1

what is the lag phase

Answer 1

individuals acclimatising to the habitat
only a few individuals in a population
rate of reproduction is slow
growth in population size is slow

Question 2

what is the log phase

Answer 2

resources are plentiful and conditions are good
reproduction happens quickly and exceed mortality
population size increases rapidly

Question 3

what is the stationary phase

Answer 3

the population size levels out at the carrying capacity
the habitat cannot support a larger population
reproduction and mortality are equal

Question 4

what are limiting factors

Answer 4

a factor that limits the growth in population size to the carrying capacity

Question 5

what is a density independent limiting factor

Answer 5

act just as strongly no matter the population size e.g. low temp

Question 6

what is a density dependent limiting factor

Answer 6

factor influences a population more strongly as population size increases e.g. resource like food, water, light and oxygen or parasites and predation

Question 7

what is a k-strategist

Answer 7

population size is determined by the carrying capacity
limiting factors exert a more significant effect as population size gets closer to carrying capacity

Question 8

characteristics of k-strategists

Answer 8

low reproductive rate
slow development
late reproductive age
long lifespan
large body mass

Question 9

what is an r-strategist

Answer 9

population size increases so quickly it can exceed carrying capacity before limiting factors have an effect
when carrying capacity is exceeded resources will be sparce or excessive waste build up may poison the species and they begin to die

Question 10

characteristics of r-strategists

Answer 10

high reproductive rate
quick development
young reproductive age
short life span
small body mass

Question 11

predator prey relationship

Answer 11

pred pop gets bigger, more prey eaten
prey pop gets smaller, less food for pred, pred pop gets smaller
less pred, prey pop gets bigger

Question 12

what is competition

Answer 12

when resources are not present in adequate amounts to satisfy the needs of all individuals in the ecosystem

Question 13

what happens when a resource is in short supply in an ecosystem

Answer 13

competition
as competition intensity increase reproduction rate lowers and death rate increase

Question 14

what is intraspecific competition

Answer 14

competition between individuals of the same species
individuals best adapted to obtaining resources survive and reproduce those less adapted die
population enters stationary phase

Question 15

what is interspecific competition

Answer 15

competition between individuals of a different species
can effect both population size and distribution within the ecosystem

Question 16

what increases interspecific competition intensity

Answer 16

the more overlap between two species niches
if tow species have the exact same niche one is out competed by the other and the other dies out

Question 17

what is conservation

Answer 17

maintenance and improvement of biodiversity including diversity between species, genetic diversity within species and maintenance of a variety of habitats and ecosystems
involves human intervention

Question 18

what is preservation

Answer 18

maintenance of habitats and ecosystems in their present condition, minimising human impact

Question 19

reasons for conservation

Answer 19

economic
social
ethical

Question 20

ethical reasons for conservation

Answer 20

every species has value and humans have an ethical responsibility to look after them

Question 21

economic reasons for conservation

Answer 21

many plants and animals are food sources, genetic diversity in wild strains may be needed in the future to breed disease resistance and improve yield
insects pollinating crops

Question 22

social reasons for conservation

Answer 22

valuable source of potentially beneficial organisms e.g. medicine
natural predators can act as pest control which is preferable to chemicals
maintaining water quality, protecting soil, breaking down waste products
maintaining climactic stability

Question 23

what is coppicing

Answer 23

stem of a deciduous tree is cut close to the ground
once cut new shoots grow from the cut surface
they new stems can be used for fencing firewood or furniture

Question 24

what is pollarding

Answer 24

the stem of the tree is cut higher up to prevent deer eating the emerging shoots

Question 25

how is a consistent supply of wood provided when coppicing

Answer 25

wood is divided into sections
one section is cut a year
by the time the first section is coppiced again the new stems are mature and ready to be cut

Question 26

what are standards

Answer 26

trees left to grow larger without being coppiced
eventually harvested to supply larger pieces of timer

Question 27

why is coppicing good

Answer 27

in unmanaged woodland trees grow large and block sunlight to the ground reducing the number of species growing there
in rotational coppicing different areas of woodland provide different types of habitat letting more light in increasing species number and diversity

Question 28

how is small scale timber production managed

Answer 28

coppicing
pollarding

Question 29

how is large scale timber production managed

Answer 29

any tree harvested is replaced by another
forest as a whole must maintain ecological function regarding biodiversity, climate mineral and water cycles
selective cutting

Question 30

what is selective cutting

Answer 30

removing only the largest and most valuable trees

Question 31

what are the three principles for sustainable management of fisheries

Answer 31

must take place at a level which allows fishing to continue indefinitely
must be managed to maintain the structure productivity, function and diversity of the ecosystem (no damage to habitat)
fishery must adapt to changes in circumstances and comply with local national and international regulations

Question 32

what is aquaculture

Answer 32

breeding raising and harvesting fish in captivity

Question 33

how humans effect animal and plant population

Answer 33

habitat disturbance
over-exploitation of resources
introduced species

Question 34

how human effects can be controlled

Answer 34

protected areas
prevent introduction and dispersion of foreign species