6.6 Populations and Sustainability Flashcards
(39 cards)
Define Carrying Capacity
The maximum population size that a habitat can support, defined by the presence of limiting factors.
Give factors that limit the maximum size of a population.
- food
- Water
- Light
- Oxygen
- Nesting sites
- Shelter
- Parasites
- Predators
Describe the pattern of a typical predator-prey relationship in terms of population change.
- Prey is eaten by predator, resulting in predator population increasing and prey population decreasing.
- Fewer prey means increased competition for food, so predator population decreases.
- Fewer predators means more prey survives, and the cycle begins again.
What is the difference between Intraspecific and Interspecific competition?
Intraspecific= competition between organisms of the same species. Interspecific= competition between organisms of different species.
Differentiate between Conservation and Preservation.
- Conservation maintains biodiversity of a habitat by allowing sustainable use of the resources there.
- Preservation maintains biodiversity of a habitat by minimising human impact.
why would we conserve and preserve habitats.
3
- Economic= food source, natural pest control, boosts tourism.
- Social= many organisms can be used in medicine, aesthetics.
- Ethical= we have a responsibility to maintain habitats for future generations.
Define sustainability.
Using resources in a way that also maintains them for future generations.
What methods allow sustainable use of an ecosystem’s resources?
- Timber production: coppicing to encourage growth, replacing felled trees, selective cutting.
- Fishing: stocks not depleted, no overfishing, can continue indefinitely
How did we fuck up in Nepal?
Terai region (Nepal). Over-exploited for use in fuel. Locals now have a responsibility to look after the forest.
Give an example of how human fucked sensitive ecosystems.
Galapagos islands. Many species endangered due to hunting and tourism. New species introduced, but caused damage to native species. Trying to find a balance.
Whats a K strategist
population sized determined by carrying capacity, have significant effects on enviroments
Whats a R strategist
population sized can surpass carrying capacity leading to sharp fall as not enough resources
K stategist examples
Large animals
• lions
• elephants
• birds
R stategist examples
small animals
• Mice
• Spiders
• insects
K stategist features
- low reproductive rate
- slow development
- long lives
- large bodiies
R stategist features
- high reproductive rate
- quick development
- short lives
- small bodiies
R stategist population graph
lag & log like normal, but then has a population Boom where exceeds carrying before bust where decreases again sharply
k stategist population graph
lag & log like normal hits carrying and remains stable with small fluctuations up & down
How would a predator prey population graph look
similar pattern with predator fluctuations slightly delayed after prey
Things that threaten Biodiversity
- New species introduction
- Habitat disruption
- over exploitation of wild populaions
Conservation strategies
- control predators & poachers
- preserve habitats
- vaccinate individuals
- raise carrying capacity by giving away shit
how do you manage timber production
coppicing & polllarding, felling
Whats coppicing
cutting stems of trees close to ground, new shoot can grow again
Whats Pollarding
cutting stems of trees higher up, new shoot can grow again
