Chapter 24 Populations And Sustainabiktig Flashcards
Features of a population graph regardless of organism contained
Phase 1- period of slow growth
- this because small numbers of organisms reproduce to increase , increase in size but delay as organisms born and grow to healthy reproductive age
Phase 2 log phase =
- no restraints on resoeuces, more organisms grow exponentially and more born
Phase three stable state,
- this because restraints now there such as space, food postings waste etc means birth and death rate the same = max population size
Then can be decline due to posit us substances and not enough resources to survive
What are portnila limiting factors abiotic and biotic
Abiotic = temperarure , light, humidity , pH , oxygen absilbaitly amount of food
Biotic = predation, disease caused by toxins, territory and completion
What is carrying capacity
This is the maximum population size an evenironment can support , at the steady stare
Birth rate and death rate stable
What other important factor affects populations
Immigration = movement of organisms into a particular area like if better conditions
Emigration = movement away ,
What are density independent and dependent factors
Density Independenzen factors are those that affect a population size that doesn’t depend on space , so these are the ones that have the GREATEST EFFECT
For example earthquakes , fires vilcanoes , regardless of size will affect crazily
But like toxic produces if big space not as much
Interspecific competition m what happens to population sizes of each
Here if two species different compete, less of both then if only one was there because less available to both
What is the competitive exclusion primciple?
What happens to less adapted
How to avoid this
This is where two different species compete, but one better adapted than other
- this leads to better adapted outfompeting and less adapted numbers dwindle and potentially become extinct in THAT HABITAT
= they may have to move out and adapt to another niche , or die out
Thus more niches harder it is for comeptive exclusion principle to happen
Red grey squirrel example
Grey introduced , can eat much more foods so outcompete red and red dwindled
What about cyclical like INTRASPECFIC COMP wxmplain graph
1) Initially when there is are plentiful resources in habitat organisms thrive and increase population
2: increased population means more need more food which system can not sustain , so numbers decrease
3) decreased numbers mean more can be supported against s completion decreases so increase
This cycle and maximum population is carrying capacity, dependent on resources
Predator prey relationship?
Interdependent, one goes up other does, so that ones down and other goes down so first goes up and eat
Other factors also affect, not as easy as this
Conservation vs preservation
Conservation is act of maintenance of biodiversity through HUMAN ACTION OR MANAGEMENT, so an active role
Preservation is Maintenance of biodiversity by restricting human involvement and interference all together , so that the ecosystem kept in Original state
Examples of conservation
Forrest stewardship scheme , captive breeding , seeds banks
What is reclamation (part of conservation)
This is the process of restoring ecosystems that have been damaged or destroyed by floods etc , also controlled burning of forests which halt succession
So basically taking back what is used to be
Example of where preservation needs to be used
WHY DO PEOPLE NOT BELIEVE IN PRESERVATION then
Virgin caves even smalelst of disturbance can cause destruction like soil being moved , as a result preservation here means complete restricted access to the area to orotect it
- However some people argue what’s the point of having a resoruces if you can’t use it at all, might aswell enjoy the cave. Etc
What is most commonly conserved and preserved
Nature is conserved, whereas only case of preservation in nature is like marine zones and nature reserves are preserved
Buildigns preserved
