Transcript Species Diversity

Species Diversity
• Two factors define species diversity:
– Species Richness:
• Number of species in the community.
– Species Evenness:
• Relative abundance of species.
Common Diversity Indices
• Shannon-Wiener index is:
H = -  pilogepi
• Simpson’s index is:
D = 1/pi2
where: pi = the proportion of each
species in the total sample
Park A
Park B
HA= -5[(1/5)ln(1/5)]= 0.70
HB= -3[(1/3)ln(1/3)]= 0.48
HA > HB
Park C
Park D
HC = 0.48
HD = 0.38
HC > HD
Park E
Park F
HE = 0.48
HF = 0.48
HE = HF
Park G
Park H
HG = 0.30
HH = 0.60
HG < HH
Mark and recapture population estimate
Single marking and single recapture
Lincoln-Petersen index
date to 1786, Laplace estimated the population size of France.
MC
N=
N
=>
R
C
=
M
M: marked animal
C: total recaptured sample
R: recaptured and marked in C
R
M
N=
R
,
p
p=
C
assumption:
1. population is closed: no migration
2. all animals are equally to be captured in each sample
3. marks are not lost, gain, and overlooked