Sucession and conservation

Question 1

What does an ecosystem being ‘dynamic’ mean

Answer 1

It changes day to day as populations fluctuate and it also changes over periods of time

Question 2

What is succession

Answer 2

Succession describes the changes an ecosystem undergoes over long periods of time.

Question 3

What are the two key things that species altering the environment results in the ecosystem being

Answer 3

1) Less suitable for the existing species. As a result the new species may out-compete the existing one and so take over a given area.
2) More suitable for other species with different adaptations. As a result this species may be out-competed by the better adapted new species.

Question 4

What is the first stage in succession

Answer 4

• The colonisation of an inhospitable environment by pioneer species.
• Pioneer species make up a pioneer community and often have features that suit them to colonisation.

Question 5

What are some examples of features that a pioneer species may have to suit them to colonisation

Answer 5

• Asexual reproduction so that a single organism can multiple rapidly to build up a population.
• The production of vast quantities of wind-dispersed seeds or spores, so they can easily reach isolated situations
• Rapid germination of seeds on arrival as they do not require a period of dormancy.
• The ability to photosynthesise as light is normally available but other food is not. They are therefore not dependant on animal species.
• The ability to fix nitrogen from the atmosphere because, even if there is soil, it has few or no nutrients.
• Tolerance to extreme conditions.

Question 6

In the UK what is the climax community of a habitat most likely to be

Answer 6

A deciduous oak woodland.

Question 7

What is the climax community

Answer 7

The community which remains more or less stable over a long period of time.

Question 8

What are the common features that emerge during any succession

Answer 8

• The non-living (abiotic) environment becomes less hostile. For example, soil forms, nutrients are more plentiful and plants provide shelter from the wind.
• A greater number and variety of habitats and niches are made
• Biodiversity increases
• There are more complex food webs
• The biomass increases

Question 9

What is secondary succession

Answer 9

• Secondary successor is when succession occurs when land has already sustained life.
• Thus land may have been suddenly altered and the process by which the ecosystem returns to its climax community is the same as primary succession but happens more quickly.

Question 10

Why is secondary succession faster than primary succession

Answer 10

• Soil already exists in which spores and seeds often remain alive.
• There is an influx of animals and plants through dispersal and migration from the surrounding area.

Question 11

What is conservation

Answer 11

The management of the Earths natural resources by humans in such a way that maximum use of them can be made in the future.

Question 12

Describe the main reasons for conservations

Answer 12

• Personal: to maintain our planet and therefore our life support system.
• Ethical: Other species have occupied the earth far longer than we have and should be allowed to coexist with us.
• Economic: Living organisms contain a gigantic pool of genes with the capacity to make millions of substances, many of which may prove valuable in the future. Long term productivity is greater if ecosystems are maintained in their natural and balanced state.
• cultural and aesthetic: Habitats and organisms enrich our lives.

Question 13

What is one key way of conserving habitats

Answer 13

• Managing succession
• This can be by preventing a change to the next stage of succession
• It can also be removing any barrier to succession to encourage it.

Question 14

What is the climax community for most of the UK

Answer 14

Deciduous woodland