SI4: An alternative synchronization index of Marquis (1988)

In flower: Tools for characterizing flowering traits

Description

SI4 thus facilitates comparison between species irrespective of flowering duration.

Usage

SI4(dd, pop, ind)

Arguments

dd	Flowering data.
pop	ID of population.
ind	ID of individual.

Details

si4=sum(xit/bit)*pt;bit=sum(xit);t=1:n

Value

si4	An alternative synchronization index of Marquis (1988).
xit	The numbers of open flowers per day.
bit	The total number of flowers of individual i during the whole flowering period.
pt	The proportion of all marked stems (inflorescence or individual) in bloom at day t.
t	Day.

Note

SI4 is a function of the numbers of open flowers per plant in contrast to Augspurger's measure SI2 which uses the mere information on whether a plant is flowering or not. SI4 accounts for full effects of variation in both the within-individual and the between-individual flowering patterns, and eventually includes the overlap of the individual flowering with the flowering of other individuals as an aspect of cross-fertilization (Bolmgren, 1998).

Author(s)

WANG,XIE

References

[1]Marquis RJ. Phenologcal variation in the Neotropical understory shrub Piper arieianum: causes and consequences. Ecology. 1988;69:1552~1565. [2]Bolmgren K. The use of synchronization measures in studies of plant reproduction phenology. Oikos. 1998;82:411~415.

See Also

nothing

Examples

a1=c(0,1,1,1,0,0,0)
a2=c(0,1,0,1,1,0,0)
a3=c(0,0,0,1,1,1,0)
a4=c(1,0,0,1,1,0,1)
a5=c(0,0,1,1,1,0,1)
a6=c(0,0,0,1,1,1,1)
pop=c("pop1","pop1","pop1","pop2","pop2","pop2")
ind=c(1,2,3,1,2,3)
dd=rbind(a1,a2,a3,a4,a5,a6)
colnames(dd)=c("D5/1","D5/2","D5/3","D5/4","D5/5","D5/6","D5/7")
C=SI4(dd,as.matrix(pop),as.matrix(ind))
C

Example output

[1] "pop1"
[1] "pop1 -SI4"
      pop1 - 1  pop1 - 2  pop1 - 3
[1,] 0.6666667 0.7777778 0.6666667
[1] "pop2"
[1] "pop2 -SI4"
      pop2 - 1  pop2 - 2  pop2 - 3
[1,] 0.8333333 0.8333333 0.8333333
$Result.si4
     n       min       max      mean         sd
pop1 3 0.6666667 0.7777778 0.7037037 0.06415003
pop2 3 0.8333333 0.8333333 0.8333333 0.00000000

flower documentation built on May 1, 2019, 9:27 p.m.