Module 6-populations and sustainability

Question 1

Define conservation

Answer 1

Maintenance of biodiversity through human action/management

Question 2

Define coppicing

Answer 2

The process of cutting down trees close to the ground to promote new growth

Question 3

Define ecosystem

Answer 3

The dynamic interaction between the biotic and abiotic factors in a given area or habitat.

Question 4

Define grazing

Answer 4

A form of human activity that can interrupt the succession of an ecosystem as animals are grazed on land to prevent growth of vegetation

Question 4

Define ex situ

Answer 4

The conservation of species outside their natural habitat in a human controlled environment

Question 5

Define in situ

Answer 5

species are conserved within their natural habitat maintaining biodiversity

Question 6

Define preservation

Answer 6

The protection of an area by restricting or banning human interference so the ecosystem is kept in its original state.

Question 7

Define species

Answer 7

2 or more organisms that can produce fertile offspring

Question 8

Define sustainability

Answer 8

The ability of an ecosystem to maintain biodiversity whilst simultaneously providing humans with resources for long term use.

Question 9

What ethical reasons do we conserve species for?

Answer 9

-Many people believe we don’t have a right to decide which organisms can stay or become extinct
-All organisms have a right to exist
-We have moral responsibility for future generations

Question 10

What social reasons do we conserve species for?

Answer 10

-Use them for activities which are beneficial to health by providing a means of relaxation and exercise
-Many people enjoy the natural beauty of ecosystems

Question 11

What economic reasons do we conserve species for?

Answer 11

-To provide resources that humans need to survive and provide an income for
-E.g rain forest species provide medicinal drugs that can be traded

Question 12

Describe the process of small scale timber production-coppicing

Answer 12

-Tree trunk is cut close to the ground
-New shoots grow from the cuts surface and mature
-Eventually the shoots are cut and in their place more are produced
-In most managed woodlands rotational copiccing takes place where the woodland is divided into sections and trees are only cut in a particular section until all have been copicced
-Copiccing then begins in a new area allowing time for the newly copicced trees to grow

Question 13

How does rotational copiccing maintain biodiversity?

Answer 13

the trees never grow enough to block out the light hence succession can’t occur so more species survive

Question 14

Describe the process of large scale timber production-felling

Answer 14

-large areas of forests are felled
-the felled trees are destroyed and will not regrow
-companies practice selective cutting which involves only removing the largest trees
-they replace trees through replanting rather than waiting for natural regeneration
-this helps to ensure biodiversity and mineral and water cycles are maintained
-they manage pests and pathogens to maximise yields
-main disadvantage is that habitats are destroyed, soil minerals are reduced and the bare soil that is left is susceptible to erosion.

Question 15

What are some examples of conservation strategies?

Answer 15

-improve public transport around the area to reduce local CO2 emissions
-organise litter picks
-invasive species are being cut back and sprayed with herbicides in attempt to kill them to stop them harming wildlife
-peat land restoration projects and block gullies to stop water draining away
-introduce walker charges to help pay for path restoration and put people off from further eroding the path
-regulated fishing zones
-introduce legislation to limit the numbers of tourists which can operate inside the reserve
-enable locals to have management rights over forests so they can act as stewards and improve biodiversity

Question 16

Describe the stages of the population growth curve

Answer 16

Phase 1-a period of slow growth, small numbers of individuals that are initially present reproduce, birth rate is higher than death rate so the population increases in size

Phase 2- period of rapid growth s the number of breeding individuals increases, the total population size multiplies exponentially, no constraints act to limit the population

Phase 3- stable state, further population growth is prevented by external constraints, population size fluctuates a bit but overall stays relatively stable, both rates and death rates are relatively equal

Question 17

What are limiting factors?

Answer 17

-prevent further growth of a population e.g disease or competition between animals

Question 18

Define carrying capacity

Answer 18

Maximum population size that can be maintained for a long period of time

Question 19

Describe interspecific variation

Answer 19

-competition between individuals in different species
-can reduce the amount of resources available slowing the rate of population growth
-outcompeting occurs when one organism is better adapted than the other

Question 20

Define intraspecific competition

Answer 20

-occurs when members of the same species compete for the same resource causes fluctuations in population size

Question 21

Describe the predator-prey relationship

Answer 21

-sizes of the predator and prey populations are interlinked
-if the prey population is small resources are limited for predators therefore decreasing the population size
-the prey population then increases as there’s less predators

Question 22

How can succession be managed?

Answer 22

Grazing-animals graze to prevent growth of vegetation
Burning-burning kills vegetation and allows secondary succession to take place

Question 23

Define sustainable resource

Answer 23

Renewable resource that is being economically exploited in such a way it won’t diminish or run out

Question 24

How is fishing sustainable?

Answer 24

-fishing quotas provide limits on the numbers of certain. Species that are allowed to be caught in a particular area
-mesh sizes can be made sufficiently large enough so that immature fish can escape and only mature fish can be caught allowing breeding to continue
-allowing commercial and recreational fishing at certain times in the year which protects breeding season of the same species allowing population size to increase to a sustainable level