Populations and sustainability Flashcards
(22 cards)
What is carrying capacity?
The maximum population size that an environment can sustainably support.
Name two abiotic factors that affect population size.
- Temperature
- Water availability
Name two biotic factors that affect population size.
- Predation
- Competition
What are the four stages of a population growth curve?
- Lag phase
- Log (exponential) phase
- Stationary phase
- Death phase
What is intraspecific competition?
Competition between members of the same species.
What is interspecific competition?
Competition between members of different species.
Why do predator and prey populations fluctuate in cycles?
Because an increase in prey allows predators to grow, which then reduces prey, causing predator decline, and the cycle repeats.
Give an example of interspecific competition in the UK.
Grey squirrels outcompete red squirrels.
What is conservation?
Active management of ecosystems to maintain or increase biodiversity.
What is sustainability?
Using natural resources in a way that meets current needs without compromising future generations.
What is preservation?
Protecting ecosystems by leaving them untouched and minimising human impact.
How does coppicing promote sustainable timber production?
By cutting trees at the base to encourage multiple stems to regrow, allowing repeated harvest without killing the tree.
What is pollarding?
Cutting trees higher up (above grazing height) to encourage regrowth and protect new shoots from animals.
How does rotational coppicing benefit woodland ecosystems?
It creates a variety of light levels and habitats, encouraging biodiversity.
Name a conservation strategy used in the Terai Arc, Nepal.
Community forestry and sustainable agriculture.
Name a conservation issue in the Galapagos Islands.
Invasive species and tourism threatening endemic species.
What treaty protects Antarctica from exploitation?
The Antarctic Treaty.
Give two methods of sustainable fishing.
- Fishing quotas
- Larger mesh sizes
Why is sustainable agriculture important?
It maintains food production without degrading the land or biodiversity.
What is biological control?
Using natural predators or parasites to control pests instead of chemicals.
What are three reasons for conservation?
- Ethical
- Ecological
- Economic
