Succession and Conservation

Question 0

What are the 2 types of succession

Answer 0

Primary succession- happens on land that has been newly formed or exposed

Secondary succession- happens on land that has been cleared of all plants, but where the soil remains

Question 1

What is succession

Answer 1

Process by which an ecosystem changes over time. The biotic conditions change as the abiotic conditions change.

Question 2

Succession occurs in stages called….

Answer 2

Seral stages

Question 3

What is a pioneer species

Answer 3

The first species to colonise an area

Question 4

What is climax community

Answer 4

The ecosystem is supporting the largest and most complex community of plants and animals it can. It won’t change much more, as it is a steady state

Question 5

Give an example of primary succession and explain it

Answer 5

Bare rock to woodland

Pioneer species colonise rocks, eg lichens grow on and break down rocks, releasing minerals
Lichens die, decomposed forming thin soil level which thickens as more organic material formed. Means other species like moss can grow
Larger plants that need more water can move in as soil deepens, eg grasses and small plants, soil continues to deepen as larger plants die and are decomposed
Shrubs, ferns and small trees begin to grow, out competing the grass and smaller plants to become the dominant species, diversity increases
Soil deep and rich enough in nutrients to support large trees, become dominant species, climax community formed

Question 6

The climax community for a particular climate is called….

Answer 6

It’s climatic climax

Question 7

Examples of climatic climaxes

Answer 7

In temperate climate there’s plenty of available water, mild temps and not much change between seasons. Climatic climax will contain large trees as they can grow in these conditions once deep soils have developed

In polar climate not much available water, temps low, massive changes between seasons. Large trees won’t ever be able to grow so climatic climax contains only herbs and shrubs

Question 8

When succession is stopped artificially the climax community is called a ….

Answer 8

Plagioclimax

Question 9

What is a plagioclimax

Answer 9

Name of a climax community when succession is stopped artificially

Question 10

Example of plagioclimax

Answer 10

A regularly mown grassy field won’t develop shrubs and trees even if climate of ecosystem could support them. The growing points of the woody plants are cut off by the lawnmower so larger plants can’t establish themselves. The longer the interval between mowing, the further the succession can progress and the more the diversity increases. But with more frequent mowing succession can’t progress and diversity will be lower, only grasses can survive being mowed

Question 11

Ways to manage succession to conserve moorland ecosystems

Answer 11

Animals allowed to graze on land. Similar to mowing, animals eat the growing points of the shrubs and trees which stops them from establishing themselves and helps to keep vegetation low

Managed fires lit. after fires, secondary succession will occur, species that grow back first (pioneer species) are the species that are being conserved. Larger species will take longer to grow back and will be removed again the next time the moor is burnt

Question 12

What is conservation

Answer 12

The protection and management of species and habitats

Question 13

Why is conservation important

Answer 13

Species are resources for lots of things that humans need eg rainforests contain species that provide things like drugs, clothes and food. If the species and their habitats aren’t conserved the resources will be lost. Resources that may be useful in the future will be lost.

Some people think we should conserve species because it’s the right thing to do

Many species and habitats bring joy as attractive to look at. Species and habitats lost if aren’t conserved so future generations can’t enjoy them

Conserving species and habitats can help prevent climate change. Eg when trees burnt co2 released, if they’re conserved this doesn’t happen

Conserving species and habitats helps to prevent the disruption of food chains, disruption could mean loss of resources

Question 14

Examples of the different ways to conserve species and habitats

Answer 14

Plants can be conserved using seedbanks

Fish species can be conserved using fish quotas

Animals can be conserved using captive breeding programmes

Any organism can be conserved by relocation

Habitats can be conserved using protected areas

Question 15

Describe how plants can be conserved using seedbanks

Answer 15

A seedbank is a store of lots of seeds from lots of different plant species, help to conserve species by storing seeds of endangered plants. Also help to conserve different varieties of each species by storing a range of seeds from plants with different characteristics. If the plant becomes extinct in the wild the stored seeds can be used to grow new plants. Seed banks are a good way of conserving plant species, large numbers of species can be conserved as seeds don’t need much space. Seeds can also be stored anywhere for a long time. However seeds have to be regularly tested to see if they’re viable (whether they can grow into a plant), which can be expensive and time-consuming

Question 16

Describe how fish species can be conserved using fish quotas

Answer 16

Fishing quotas are limits to the amount of certain fish species that fisherman are allowed to catch. Scientists study different species and decide how big their populations need to be for them to maintain their numbers. They they decide how many it’s safe to take without reducing the population too much. International agreements are made that state the amount of fish each county can take, and where they’re allowed to take them from. Fishing quotas 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. There are problems with fishing quotas, many fishermen don’t agree with scientists who say that the fish numbers are low. Some think quotas will cause job losses

Question 17

Describe how animals can be conserved using captive breeding programmes

Answer 17

Captive breeding programmes involve breeding animals in controlled environments. Species that are endangered can be bred in captivity to help increase their numbers. Animals can have problems breeding outside their natural habitat. Animals bred in captivity can be reintroduced to the wild. This increases their numbers in the wild which can help to conserve their numbers. Reintroducing animals in the wild can cause problems, reintroduced animals could bring new diseases to habitats, harming other species living there

Question 18

Describe how any organism can be conserved by relocation

Answer 18

Relocating a species means moving a population of a species to a new location because they’re directly under threat eg from poaching, or the habitat they’re living in is under threat eg from rising sea levels. The species is moved to an area where it’s not at risk but with a similar environment to where it’s come from so species is still able to survive. It’s often used for species that only exist in one place. Helps to conserve species because they’re relocated to a place where they’re more likely to survive so their numbers increase. Relocating species can cause problems though eg native species in the new area may be out-competed by the species that’s moved in and become endangered themselves

Question 19

Describe how habitats can be conserved using protected areas

Answer 19

Protected areas such as national parks and nature reserves protect habitats by restricting urban development, industrial development and farming. Habitats in protected areas can be managed to conserve them eg by coppicing- cutting down trees in a way that lets them grow back, so they don’t need to be replanted. This helps conserve the woodland but allows some wood to be harvested. There are problems with using protected areas to conserve habitats though eg national parks are also tourist destinations (many are funded by revenue from the tourists that visit). Means there’s conflict between the need to conserve the habitats and the need to allow people to visit and use them

Question 20

Conservation relies on science to make informed decisions. Explain

Answer 20

Scientists carry out research to provide info about conservation issues. This info can be used to make informed decisions about which species and habitats need to be conserved and the best way to conserve them