Intraspecific Competition Flashcards
Example of density dependence…
Barnacle in North Wales settling as Larvae and establishes as adults 2 years later
Overcompensating Density Dependence
Increased intitial numbers leading to decreases in final numbers
What is fecundity density dependence?
Per capita birth rate as intraspecific competiton increases
Law of Constant Final Yield
This is competition effects resulting in constant biomass from high density and resource limitation, as size of individuals proportionally decrease
How many growth/survivability depend on age?
Yield from sowing of seeds increased with density of seeds sown in carrots
How does law of constant final yield work?
Plant weight reduced at first harvest at higher densities, but increasing plant size interfered with each-other at increasingly lower densities
How might density measurements be variable sptially?
Insect density on plants is no of plants divided by no of insects, however intesnity only true if all plants have 10 insects each
Example of densitiy dependence competition effects?
Trees clumped together with reduced branch length, affected by proximitiy more than density
How can intra comp be quantified?
Defining k, that being initial density B - final density A
How does k relate with density?
K constant at low densities, being density independence, at K increases with inital density
Density on a graph…
Per capita birth and death rate cross, below where birth exceeds death, being a stable equilibrium
Why is carrying capacity unrealistic?
Environmental fluctutations, and factors external of Intra
Why are mathematical models important?
Allow a common example to be expressed, exhibit properties that didn’t know system possesed, integrates indefinitely any assumptions
Equation for discrete breeding systems
Nt+1 = NtR/(1+aNt)
What does Nt+1 = NtR/(1+aNt) represent?
Population increase is limited by intra comeptition, where previously unrealistic R incorporated actual net reproductive rate that decreases inversely proprotional to population size.
