Populations and Sustainability

Question 1

What is the carrying capacity of an ecosystem?

Answer 1

• The maximum number of individuals of a species that an ecosystem can support
• Determined by limiting factors
• When a population reaches this, its growth slows or stops, and may even reduce

Question 2

What are the limiting factors for carrying capacity?

Answer 2

Food, shelter, water and mates

Question 3

What is interspecific competition?

Answer 3

When individuals of different species compete for resources such as food, water, breeding sites, light, space or shelter

Question 4

What is the difference between conservation and preservation?

Answer 4

• Conservation involves the sustainable use and management of natural resources, including the maintenance of biodiversity through human action or management
• Preservation involves protecting natural areas by restricting or banning human interference, so an ecosystem is kept in its original state

Question 5

What are the 3 main reasons why conservation is important?

Answer 5

• Economic - ecosystems provide resources for human survival and income such as drugs and food
• Social - ecosystems provide natural beauty and areas for activities that are beneficial to health and well being
• Ethical - all organisms have a right to exist and play important roles in ecosystems, humans have a moral responsibility to protect this

Question 6

What are some techniques used in sustainable, small scale timber production?

Answer 6

• Coppicing - technique where a tree trunk is cut close to the ground, and new shoots that form are cut when they mature
• Rotational coppicing - trees are coppiced in one area at a time, allowing time for regrowth before the same area of trees is coppiced again
• Pollarding - similar to coppicing, but the tree trunk is cut higher up so animals cannot consume new shoots when they appear

Question 7

What are some sustainable fishing techniques?

Answer 7

• Fishing quotas - set limits based on scientific assessments to regulate the numbers of certain species caught in specific areas
• Using nets with different mesh sizes - ensure nets have a minimum mesh size to catch only targeted fish species while allowing smaller and non target species to escape
• Only allowing fishing at certain times of the year

Question 8

What are some techniques used in sustainable large scale timber production?

Answer 8

• Selective cutting - only removing the largest trees
• Replanting
• ## Managing pests and pathogens - maximises yields