Module 6: Populations and sustainablity

Question 1

State the meaning of a population

Answer 1

all the organisms of one species in one habitat

Question 2

What can affect a population size

Answer 2

Limiting factors can be biotic or abiotic
Other things include migration
Or density factors like a fire or earthquake

Question 3

What does interspecific competition mean

Answer 3

competition between different species competing for things like food, habitat

Question 4

What is the competitive exclusion principle

Answer 4

Weaker species are out-competed so their number falls

for example grey squirrels were introduced these outcompete red squirrels

Question 5

What does intraspecific competition mean

Answer 5

Competition between the same organisms for food, habitat, mates

Question 6

Can you draw a graph about intraspecific competition and explain

Answer 6

At first, the resources are in excess so organisms are able to reproduce and survive

Then this increases the population meaning there is not food for everyone, so the population decreases

Once there are more resources available the population will increase as more animals will reproduce and survive

Question 7

What is the maximum stable population size of a species that an ecosystem can support called

Answer 7

Carrying capacity

Question 8

Can you draw a graph that shows the predator and prey relationship and explain

Answer 8

As the number of prey increase (more food for predators) so predator population increases

Due to this more prey get eaten, so the prey population decreases

This then decreases the predator population as there is not enough food. Which then increases prey population etc

Question 9

What is conservation

Answer 9

Protection and managment of ecosystems

Question 10

Why is conservation important

Answer 10

economic reasons: provide drugs, food, clothes with all parts of the trade

ethical reasons: some people believe that organisms have the right to exist and not be extinct because of human activity, also we should conserve ecosystems for future generations

social reasons: people find them attractive, brings them joy

ecological reasons: It can help prevent climate change for example not burning trees means less CO2. Climate change can affect predator-prey relationships

Question 11

What does preservation mean

Answer 11

Protection of an area by restricting human interference

Question 12

What is sustainability and the aims

Answer 12

ensure that there are enough natural resources for future generations to use

Aim to help LEDC

help balance resources between LEDC and MEDC

Preserving the environment and protecting biodiversity

Question 13

How has timber production been made sustainable

Answer 13

small scale- coppicing

• cutting near to a base of trees allows
• generates more branches
• there will be no competition as no trees will block sunlight or succession so it helps maintain biodiversity

Pollarding

• cut the tree higher up
• makes more branches and herbivores can’t eat them

Large scale timber production

• selective cutting (protect endangered ones) have to replant trees away from each other to reduce competition
• manage pests and pathogens
• ensures protection for locals

Question 14

How is sustainable fishing enforced

Answer 14

• Fishing quotas to avoid over fishing
• using a bigger net mesh means that adult fish are caught
• restrict the time of year you can fish to protect breeding season
• fish farming- maintain protein supply
• stop the loss of wild species

Question 15

How is human activity controlled in the Lake district

Answer 15

• similar to the park authority of Snowdonia
• replant trees
• promote opportunities for understanding lake district

Question 16

How is the Masai Mara managed?

and what conservation techniques are in place

Answer 16

how its managed

• grazing limited to the edge of the reserve
• use of ecotourism (helps locals, does not exploit area or community)

Conservation

• Made a programme to conserve rhinos (hired park rangers and provided with the necessary equipment)
• number of scientific projects there

Question 17

how is sustainability promoted in terai region

Answer 17

Sustainable forest
-support local forestry groups (which has improved soil, employment, created sustainable wood sources)

-also promote sustainable agriculture (growing nitrogen-fixing plants, improving irrigation facilities)

Question 18

How can you conserve and preserve a peat bogs

Answer 18

Preservation and conservation

• Ensure peat bog is conserved (as wet as possible)
• Remove seedling trees from the area (trees require lots of water)
• Use controlled grazing to increase the biodiversity of peat bogs

Question 19

what is meant by conservation?

Answer 19

conservation is the protection and management of ecosystems so that the natural resources in the, can be used without them running out.

Question 20

how is conservation a dynamic process?

Answer 20

conservation is a dynamic process- conservation methods need to be adapted to the constant changes (caused naturally and by humans) that occur within ecosystems.
-it involves the management of ecosystems- controlling how resources are used and replaced.

Question 21

how does conservation involve reclamation?

Answer 21

• restoring ecosystems that have been damaged or destroyed so they can be used again
• e.g. restoring forests that have been cut down so they can be used again.

Question 22

what is an economic reason for conservation?

Answer 22

• ecosystems provide resources for lot of things that humans need,
• e.g. rainforest contain species that provide things like drugs, clothes and food.
• These resources are important because they’re traded on a local and global scale.
• If the ecosystems aren’t conserved, the resources that were used will now be lost, so there’ll be less trade in the future

Question 23

what is a social reason for conservation?

Answer 23

• most ecosystems bring joy to people because they are attractive to look at + people us them for activities, e.g. birdwatching and walking.
• The species and habitats in the ecosystems may be if they aren’t conserved, so future generations won’t be able to use and enjoy them.

Question 24

what is a ethical reason for conservation?

Answer 24

• some people think we conserve ecosystems simply because it’s the ‘right’ thing to do- e.g. most people think organisms have a right to exist, so they shouldn’t become extinct as a result of human activity.
• some people think we have a moral responsibility to conserve ecosystems for future generations, so they can enjoy and use them.

Question 25

what is a ecological reason for conservation?

Answer 25

• conserving species and habitats can help to prevent climate change.
• e.g. when trees are burnt , CO2 is released into the atmosphere, which contribute to global warming.
• If the trees are conserved, this doesn’t happen.
• conserving species and habitats also helps to prevent the disruption of food chains can have a knock-on effects on other organisms. e.g. some species of bear feed on salmon and the bear population

Question 26

what is meant by preservation?

Answer 26

preservation is different from conservation- it’s the protection of ecosystems so they’re kept exactly as they are.
-nothing is removed from a preserved ecosystem and they’re only used for activities that don’t damage them.

Question 27

why does it mean ‘to manage ecosystems in a sustainable way’?

Answer 27

-ecosystems can be managed to provide resources in a way that’s sustainable- this means enough resources are taken to meet the needs of people today, but without reducing the ability of people in the future to meet their own needs.

Question 28

what are 6 things that need to be done in order to ensure that the cutting down and replanting of trees is done carefully and successfully?

Answer 28

1-trees are cleared in strips or patches- woodland grows back more quickly in smaller areas between bits of existing woodland than it does in larger, open areas.

2-the cleared strips or patches aren’t too large or exposed- lots of soil erosion can occur on large areas of bare ground. If the soil is eroded, newly planted tress won’t be able to grow.

3-timber is sometimes harvested by coppicing- cutting down trees in a way that lets them grow back. This means new trees don’t need to be planted.

4-native tree species tend to be planted in preference to non native species. This is better for biodiversity because native species have long- established interactions with other native species (e.g. plants, fungi, animals), so their presence should help species thrive in an area. also some species might not adapt to the presence of non- native tree species.

5-planted trees are attached to posts to provide support, and are grown in plastic tubes to stop them being eaten by grazing animals- this makes it more likely the trees will survive to become mature adults.

6-trees aren’t planted too close together- this means the trees aren’t competing with each other for space or resources, so they’re more likely to survive.

Question 29

what does overfishing lead to?

Answer 29

overfishing has led to a decline in fish stocks in many parts of the world.
-This may lead to some species of fish disappearing altogether in some areas, and has the potential to severely disrupt ocean food chains.

Question 30

why are fish important?

Answer 30

fish are an important part of many people’s diets and fishing provides employment for many people, so we need to maintain fish stocks at a level where the fish continue to breed.

Question 31

what is meant by sustainable food production?

Answer 31

having enough food without using resources faster than they renew.

Question 32

what are fishing quotas?

Answer 32

fishing quotas are limits to the amount of certain fish species that fishermen are allowed to catch

Question 33

what is the purpose of fishing quotas?

Answer 33

fishing quotas are supposed to help to conserve fish species by reducing the numbers that are caught and killed, so the populations aren’t reduced too much and the species aren’t at risk from becoming extinct.

Question 34

how are fishing quotas set?

Answer 34

• to set fishing quotas, scientists study different species and decide how big their populations need to be for the, to maintain their numbers.
• then they decide how many it’s safe for fishermen to take without reducing the population too much.
• International agreements are then made (e.g. the Common Fisheries Policy in the EU) that state the amount of fish each country can take, and where they’re allowed to take them from.

Question 35

what is the problem with fishing quotas and how do we try to deal with it?

Answer 35

• there are problems with fishing quotas though- e.g. fish of the wrong species or size are still caught, but they end up being thrown back into the sea, often dead or dying, because the restrictions don’t allow the fishermen to bring them ashore.
• However, new rules for the Common Fisheries Policy are banning the discarding of fish like this and the whole catch will have to be brought ashore to be counted against the quotas.

Question 36

why do governments set restrictions on mesh sizes?

Answer 36

• governments can set limits for the mesh size of the fishing net, which vary depending on what’s being fished.
• this reduces the number of ‘unwanted’ and discarded fish that are accidently caught,
  e. g. shrimp caught along with cod, as the ‘unwanted’ species can escape through the holes in larger meshes. It also means that younger fish will slip through the net, allowing them to reach breeding age.

Question 37

what is the problem with the mesh size regulations startergy?

Answer 37

-it can be difficult to determine exactly ow big the mesh size should be n areas where several different fish species are fished for at the same time.
+ 2 nets, each of which meets regulations, should be used one inside the other so that their meshes overlap- effectively reducing the reported mesh size.

Question 38

describe the ecosystem of the Terai Arc

Answer 38

• the Terai Arc is an area of forest and grassland s on the border between Nepal and India.
• A variety of plants and animals are found there, including endangered species like the Bengal tiger and Asian elephant.
• Nearly 7 million people also live in this area and many of them depend on the forest’s resources to survive.

Question 39

why do we need to conserve and preserve the Terai Arc?

Answer 39

• areas of the forest are being destroyed to make way for more housing and other development- this destruction of habitats brings humans and animals into closer contact and increases conflict between the 2.
• e.g. elephants can eat and trample crop fields and tigers can kill livestock.
• This increases the of these animals being shot and killed.

Question 40

describe the Maasai Mara

Answer 40

• The Maasai Mara is a national reserve in Kenya.
• It’s a large area of grassland (savannah) which is home to huge populations of wildebeest and zebra, as ell as lions and cheetahs.
• The Maasai Mara is named after the Maasai people who live in the area.

Question 41

why are we attempting to conserve and preserve areas in the Maasai Mara?

Answer 41

• the Maasai people traditionally earn a living y raising livestock, such as cattle.
• this can bring them into conflict with conservationists-
  e. g. overgrazing by livestock can destroy grassland for wildlife.

Question 42

how are we attempting to conserve and preserve the masai mara

Answer 42

• conservation trusts are working with the Maasai people to help them make money from their land through conservation and ecotourism projects rather farming, and to farm in a sustainable way.
• so, the economic needs of the Maasai people are met, while still allowing the area to be conserved.

Question 43

describe UK peat bogs (what they are)

Answer 43

• lots of upland parts of the UK are home to pea bogs- areas if wet peat.
• These peat bogs store water and CO2, and are home to lots of different plants and animals, such as Sphagnum moss- these mosses actually help the peat bogs by retaining water.

Question 44

why are we attempting to conserve and preserve areas in the UK peat bogs?

Answer 44

• farmers use the peat bogs to graze sheep and deer.
• However, his can lead to conflict with conservationists because overgrazing causes loss of moss species, soil compaction (which increases water runoff down sheep paths, taking sediment with it) and general peat bog erosion.

Question 45

why are peat bogs really useful to humans?

Answer 45

By holding water in the landscape they can help to reduce flooding, and by storing CO2 they may be useful in combatting climate change.

Question 46

what are 5 ways that human activities have effected the Galapagos Islands?

Answer 46

1-exploeres and sailors that visited the Galapagos Islands in the 19th century directly affected the populations of some animals by eating them.

2-Non-native animals introduced introduced to the islands eat some native species. This has caused a decrease in the populations of native species.

3-Non-native plants have also been introduced to the islands. these compete with native plant species, causing their populations to decrease.

4-Fishing has caused a decrease in the populations of some of the sea life around the Galapagos islands.

5-A recent increase in tourism (from 41000 tourists in 1991 to over 210000 in 2014) has led to an increase in development on the islands. The population of the islands has also increased due to the increases opportunities from tourism. This could lead to further development and so more damage to the ecosystems.

Question 47

what are some measures that have been taken to help control the impact of humans on the Galapagos Islands?

Answer 47

1-eradiaction programmes have removed wild goats from some of the smaller islands and wild dogs from the largest islands

2-Quinine trees are kept in check using chemical herbicides and by uprooting young trees.

3-A marine protected area has been established around the islands, which sets limits and controls of fishing.

4-When people visit the Galapagos National Parks they are expected to follow a list of rules, which includes not bringing any live plants or animals onto the islands, or moving them between the islands.

5-people are also only allowed to visit the Galapagos National Parks in the company of a licensed guide.

Question 48

what effects have human activities had on Antartica?

Answer 48

-historically, hunting of various animals around Antarctica was a large industry. in the 20th century, whaling in the waters surrounding Antarctica was intense, leading to a huge decrease in whale numbers.
+ this hunting led to the Antarctic blue wail being critically endangered, and the population of other species of whale being severely depleted.

• seal hunting in the 19th century drove the Antarctic deal to the brink of extinction.
• The seas around Antarctica are still being exploited by fishing vessels.
• Human activities can also lead to problems with pollution.
• In the past, visitors to Antarctica have dumped sewage into the sea and left behind rubbish.
• shipping accidents have led to i spills, which severely affect wildlife.

Question 49

what measures have been taken to help control the impact of humans on Antarctica?

Answer 49

1 -the continent of Antarctica is internationally protected by the Antarctic Treaty, and is now treated as a nature reserve.

2 -commercial whaling was banned completely in the ocean surrounding Antarctica in 1994, and seal hunting has been banned for longer. Populations of the Antarctic fir seal have now recovered, but the populations of many species of whale are still considered to be dangerously low.

3 -fishing still occurs, but within limits set with the help of scientists

4 -to reduce the impacts of pollution, all waste apart from food waste and sewage must be taken away by ship for disposal in other countries. Many research stations now treat their sewage before releasing it, to reduce its effect on the environment.

5 -Ships that use thick oil as a fuel are now banned from Antarctic waters, as heavy oil spills are likely to cause more damage and be harder to clean up than spills of lighter fuels.

6 -to prevent damage by tourists, tourist restrictions have been introduced- e.g. tourists are only allowed on land at certain locations for a few hours.

Question 50

what effects have human activities had on the Lake District and Snowdonia?

Answer 50

-many of the visitors to the Lake District go walking on the region’s footpaths. This leads to the erosion of the footpaths and the loss of soil from hillsides.
+ Soil that ends up in waterways and lakes can disrupt the of pH of the water, causing knock-on effects for wildlife.
+ As the paths become harder to walk on, people can start to trample and destroy the sensitive vegetation either side of the paths.

=It’s a similar story in Snowdonia- a lot of rain falls in the Snowdonia hills, which leads to the erosion of the paths. Walkers often trample the surrounding vegetation as they to to walk around the floods.

-the Lake District also has problems with water pollution in some areas.
+Phosphates in fertilisers used on farms, in detergents used for cleaning clothes and dishes and in water released by local sewage works have accumulated in some of the lakes.
+these act as fertilisers for algal growth, and can contribute to algal blooms, which deoxygenate the water and can kill fish.

Question 51

what are some measures that have been taken to help control the human impact on the Lake District and Snowdonia?

Answer 51

• to counteract footpath erosion in the Lake District, conservation charities and the Lake District National Park Authority attempt to carry out regular repair and maintenance work on the paths and encourage the regrowth of damaged vegetation.
• Walkers are also educated about the importance of sticking to the paths and now taking short cuts, as these increase erosion.
• In Snowdonia, volunteers have dug drains next to the paths to prevent them from flooding.
• The pollution problem in the Lake District has been tackled by improving sewage treatment in the area, supplying grants to local farmers to improve farming practices and encouraging local businesses and residents to only use detergents that are phosphate- free

Question 52

how does global warming threaten Antartica?

Answer 52

-changes in sea temperature could affect algae and fish populations, and the populations of animals that feed on them. Melting sea ice may negatively affect some of the species of penguin that breed in these areas.