ENVS 1126 Chapter : Chapter 4
Document Summary
Logistic: population where growth is rapid (exponential growth) and stabilizes. Logistic growth: rate of change= rn (1- (n/k)) R selected species tend to always be in the exponential growth (crashing and growing repeatedly) We are in exponential growth (predicted to stabilize in 2200 at 10 billion)- logisitc. Ex: when whale raises offspring to become adult with a lot of care, low biotic potential, hugh recruitment; opposite for fish with lots of eggs and abandon. R have high biotic potential but poor recruitment most of the time. K have low biotic potential but good recruitment (k strategists: long life span large animals fewer offspring long involved parental care, opposite for r strategists) Density- dependent limiting factors are needed to regulate a population, population becomes too big, these factors force pop to go down eg food shortage; predator prey interaction. Density independent factors can by imp but are not associated with regulation eg forest fires- doesn"t really do anything.