Populations And Sustainability 2 Flashcards
Population growth curve
Phase 1 - period of slow growth
Phase 2 - rapid growth
Phase 3 - stable state north and death rates are relatively equal
Limiting factors
Prevent further growth of a population
- abiotic factors - temp light pH availability of water
- biotic factors - predators disease competition
Migration
Immigration- movement of indiv into a particular area increased pop size
Emigration- movement of individuals away from a particular are decreases pop size
Density dependent factors
these limiting factors increase with the size of the population and limit growth as population size increases
Competition types
Interspecific
Intraspecific
Interspecific
Competition between different species for the same resource
Less adapted species becomes outcompetes and numbers decline
Intraspecific competition
Same species compete for same resource
Greater availability of resource the population increase can be supported
Intraspecific competition stages
Stage 1- resource is plentiful all organisms reproduce once population
Stage 2 - resources limited due to more numbers populations decrease
Stage 3 - less competition population increases
Predator prey population relationship
Stage 1- increase in prey pop more food for predators (increase pop of pred.)
Stage 2- increased predator population eats more prey decreasing prey pop
Stage 3- Intraspecific competition occurs in predators decrease predator pop
Stage 4- reduced predator more prey reproduce cycle begins again
Conservation
Maintenance of biodiversity through human action or management
Natural resources used without running out - sustainable development
Reclamation
Restoring ecosystems that have been damaged or destroyed eg by floods or building development
Preservation
Protection of an area by restricting/ banning human interference
Importance of conservation
Economic- provide resources humans need and to provide an income
Social- enjoy the natural beauty of wild ecosystems
Ethical - all organisms right to exist and most play important role in ecosystem
Sustainable resource
A renewable resource that is economically exploited in such a way that it will not run out
Aims of sustainability
Preserve environment
Ensure resources are available for future
Allow humans in all society to live comfortably
Enable less economical developed countries to develop exploiting Nat resources