6.3.2 Populations And Sustainability

Question 1

What are the key features of a population curve

Answer 1

Lag phase- reproductive rate is initially slos as population adapts to new conditions
Log phase- population increases exponentially no significant restrictions
Stable phase- limiting factors ( density dependent factors) inhibit further growth carrying capacity is reached

Question 2

What are the types of competition

Answer 2

Interspecific- competition between different species can lead to competitive exclusion if niches overlap too much
Intrasepecific- competition within a species for resources

Question 3

What is a predator prey relationship

Answer 3

Increased prey population means more food is available for predators, causing an increase in predator population. More predators means more predation so prey population decreases. Less prey means less food available for predators so the predator population falls. Less predators means more prey able to survive increasing prey population, cycle repeats.

Question 4

What is conservation

Answer 4

Protection and management of ecosystems to ensure resources are used sustainably to increase biodiversity through human action

Question 5

What are the benefits of conservation

Answer 5

Economic- provides resources on a local and global scale, colourism is a major income for many places.
Social- recreational and aesthetic. Value to enhance well being and quality of life
Ethical- all organisms have the right to life, humans have moral responsibility to prevent the extinctions we are casuing

Question 6

What is preservation

Answer 6

Maintains ecosystems in undisturbed state by restricting, banning resource extraction and human interference.

Question 7

What are methods of sustainable timber

Answer 7

Coppicing- cut trees close to ground and harvesting once mature
Pollarding- cutting trunk higher up to protect from grazing
Selective cutting- removes larger trees to allow growth of younger trees

Question 8

What arevmethods of sustainable fishing

Answer 8

Fishing quotas- limits based on scientific assessments to regulated numbers allowed to be caught
Mesh sizes- minimum size to catch targeted fish and allowing juveniles to escape
Aquicultuee- sustainable source of protein conserving wildlife populations
Seasonal restrictions- protect fish during breeding season allowing populations to recover