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5 Biodiversity and Ecology III - Coggle Diagram
5 Biodiversity and Ecology III
Population Ecology
study of factors that affect population
how and why population changes over time
reflect no. of births and deaths , migrating to and from
Population Growth
rate of increase/ decrease in population size over time
causes: diseases, family planning, infertility, pollution, scarcity of resources
2 types
logistic curve "S"
stable ecosystem when population line align with c.c line
diminishing phase
stationery phase
log phase
lag phase
exponential curve "J"
lag phase
exponential phase
exponential growth occur under ideal condition
curve drops after max. value achieved
boom and bust
Overall change in population caused by
Natality
Mortality
Immigration
Emigration
Change in population size=(birth+immigrants)-(death+emigrants)
Biotic Potential
maximum population growth rate possible for a species (in an ideal unlimited environmental resources)
never achieved because nature has more than 1 limiting factors
abiotic factor
light
humidity
temp.
food
climatic condition
humidity
biotic factor
competition
predation
parasitism
mutualism
Carrying Capacity (K)
maximum no. of individuals of a species that an environment can indefinitely support without any significant negative impacts
resources increase, c.c increase vice versa
changing constantly
population size increase when below its c.c
population size decrease when above its c.c
Survivorship Curve
percentage of organisms that are able to survive
plotted by no. of surviving individuals against age
Type I
senescence(old age)
high probability of surviving at young and reproductive age
small no. of offspring
Type II
uniform death rate from young to old
parental care provided
Type III
vry few organisms survive their younger age
pretty long lives after making through youth
lots of offspring at once
little parental care
Population Strategies
r-strategy
"J" curve
fast reproductive rate with more offspring
less parental care
high mortality
small inidividuals
short life span
fast to mature
early reproductive age
elephant
K-strategy
"S" curve
slow reproductive rate with few offspring
more parental care
slow to mature
later reproductive age
long life span
large individuals
mice
Causes loss of diversity
habitat loss
over-exploitation of living resources
global climate change
pollution of soil, water and atmosphere
invasion by introduced species
new species introduced accidentally
displace old species in competition
no natural predator
Conversation measure
In situ
maintain in their natural habitats
Eg: Taman Negara
Ex situ
maintain outside natural hebitats
in facilities: arboreta, botanical garden, zoos, seed gene banks
Sustainable development
process of balancing need of human for economic and social development with need to protect natural and built environments
avoid environmental degradation
save water, electricity, recycle, reusable bags