DATA SET IDENTIFIER: LFDP phenology plot seedlings – 16 ha plot
PROJECT TITLE: LFDP phenology plot seedling dynamics: recruitment, growth and mortality
PROJECT DESCRIPTION: Seedling plots associated with the flowering phenology baskets were added
to the Luquillo site monitoring program in 2007 in order to investigate the relationships between
flowering and seed production, and seedling establishment, growth, and mortality. We are monitoring all
woody seedlings in 360 one-square-meter plots in a sub-tropical moist forest. There is no lower size
threshold. Data on temporal and spatial patterns of seed rain and seedling recruitment allow tests of
hypotheses concerning causes of inter-annual variation and roles of different mechanisms in facilitating
species coexistence.
RESEARCH LOCATION: The 16-ha Luquillo Forest Dynamics Plot at El Verde Research Area in El
Yunque National Forest, Puerto Rico. The southwest corner of the FDP is located at 217503.6 easting
and 54394.1 northing in the Puerto Rican Planar coordinate system
DATA SET CREATOR: Jess K. Zimmerman
DATA SET CONTACTS: Jess K. Zimmeran (email: [email protected]) and Christopher Nytch (email:
[email protected])
DATA SET ABSTRACT: These data on temporal and spatial patterns of seedling recruitment in
conjunction with data on flower and seed rain production allow tests of hypotheses concerning causes of
inter-annual variation and roles of different mechanisms in facilitating species coexistence. The data are
being used to, among other things 1) quantify seasonal and inter-annual variation in reproductive output
in tropical plant populations and communities; 2) analyze relationships between reproduction and a
variety of hypothesized local and regional climate drivers; 3) evaluate evidence for long-term directional
trends which could reflect responses to anthropogenic global change; 4) quantify spatiotemporal variation
in seed arrival and seedling recruitment of individual species; 5) analyze associated evidence of
recruitment limitation, life history trade-offs, density dependent recruitment and regeneration niche
partitioning; and 6) evaluate how these processes interact with inter-annual variation in climate and plant
reproduction.
DATA SET METHODS: We census seedlings once each year, in 360 1 m2 subplots. Three subplots are
grouped together around each of 120 seed traps in the LFDP. Seed traps are located at 8 m intervals
along pre-existing trails and 8 m from on either side of the trail. The three seedling subplots are located 2
m from each seed trap at polar coordinates chosen in a stratified random manner (i.e., between 1-120
degrees, 121-240, and 241-360) but rejecting locations that fell in pre-existing trails.
Data are recorded during the annual dry season from January to April. Plot substrate (leaves, bare soil,
rock, herbs, dead wood, live wood), is assessed for each plot, with percent coverages estimated to the
nearest 5% and totaling 100%. The number of grasses and Heliconia sp. culms are also counted in each
plot, and the height of the tallest grass and all Heliconia culms is measured from the ground to the tip of
the blade/tallest leaf. A densiometer is used to take measurements of canopy cover directly above the
center of each seedling plot. General gap size is assessed by looking up at the tree canopy overhead and
recording whether seedlings see a large (many large tree crowns missing), medium (several large tree
crowns missing), small (one large tree crown missing), or no gap.
In each plot, all woody-stemmed (lianas included) new recruits and surviving seedlings >0 cm (i.e., there
is no lower size threshold) and less than 1 cm diameter at 130 cm height are identified to species (using a
six letter code, and marked with permanent, uniquely numbered tags. Seedlings for which species cannot
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be determined are labeled as “Unknown.” The predominant substrate on which that the seedling is
growing is noted. Seedling height (excepting palms) is measured from the ground (or root collar or seed
if that is visible) along the length of the stem to the apical meristem. For all seedlings >= 10 cm in height,
the diameter is measured at the widest axis of the base of the stem. For stems >=130 cm in height, the
diameter at 130 cm is also recorded. For plants with multiple stems, height is measured only for the
tallest stem. The location of each seedling is mapped relative to other seedlings and the plot boundaries.
Old tags found on the ground or on dead stems are removed from the plot, and tags that cannot be located
are recorded as “Not Found.” We continue to follow seedlings that grow to exceed 1 cm diameter at a
height >=130 cm.
For palms, seedling height is measured as the distance from the ground to the tip of the tallest/longest
leaf. Stem height of palms is recorded from the ground to the top of the stem between the last pair of leaf
scars, below where the oldest frond is attached. Diameter of palms is measured at the widest part of the
base. When the palm has an obvious woody stem that is clear of dead fronds, a second diameter
measurement at the top of the stem, or at 1.3 m, whichever is lower.
For woody vines germinating in the plot, height is measured as the length from the ground along the vine
to the apical meristem or the point where the vine leaves the plot. If the height/length of the vine is >=1.3
m (within the plot), the diameter is also measured at 1.3 m.
Comments are recorded indicating if a seedling stem is broken or has died back, if there is evidence of
herbivory or lack of leaves altogether, and tag numbers of large trees with census tags that are located
within the seedling plot.
Seedling identifications have been made by Maria Aponte (2007-2008) and John Bithorn (2007-2010).
This FDP is described in greater detail at
http://luq.lternet.edu/research/projects/forest_dynamics_description.html. Further information and data
pertaining to this study will be available in the near future at
http://luq.lternet.edu/data/databasesbycategory.html#VegetationDyn
DATA FILE NAME: LFDP_Seedlings_Phenology.txt (Tables 1 & 2 describe the variables)
DATA FILE TYPE: Tab delimited ASCII
NUMBER OF RECORDS: 28664
DATA SET MOST RECENTLY UPDATED ON 20101201.
METADATA MOST RECENTLY UPDATED ON 20110106.
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Table 1. Description of variables in the Luquillo seedling dynamics Data Set
Abbrevia
tion
(as it
appears
on the
data
file)
NAME OF
VARIABLE
DEFINITI
ON OF
VARIABLE
PLOT
NUMBER
PLOT
SUBPLOT
TAG
DATE
XXXX
SPECIES
XXXX
A/D/NF/N
XXXX
HEIGHT
XXXX
DIAME
TER
XXXX
SUBSTR
ATE
XXXX
PALM
STEM HT
XXXX
DIAMET
ER @ 130
XXXX
DIAM @
TOP PALM
STEM
XXXX
COMMENT
S XXXX
Phenology
trap plot
number
Phenol
ogy
trap
plot
number
and
subplo
t
Numeri
cal
combin
ation of
phenol
ogy
trap
number
and
seedlin
g
subplot.
Subplot
A is
represe
nted as
.1,
Subplot
B as .2,
and
Subplot
C as .3
Subplot
name
Tag
Number
Date in
year
XXXX of
collect
ion of
seedlin
g data
Species
code in
year XXXX
Seedling
status
in year
XXXX
Seedlin
g
height
in year
XXXX
Seedli
ng
Diamet
er in
year
XXXX
Seedlin
g
substra
te in
year
XXXX
Palm
stem
height
in year
XXXX
Diamete
r at
130 cm
height
in year
XXXX
Diameter
at top of
palm stem
in year
XXXX
Comments
in year
XXXX
Name of
subplot
associate
d with
each
phenolog
y trap.
Unique
identificat
ion
number
(integer
or
decimal)
given to
each
recorded
seedling
in a plot.
Date in
year
XXXX of
collection
of
seedling
data
(mm/dd/
yyyy)
Six letter
code*
(First 3
from Genus
and last 3
from the
species)
in year
XXXX
Status
of
seedling
in year
XXXX.
A=Alive,
D=Dead,
NF=Not
Found
Height
of
seedlin
g
measure
d in
year
XXXX
from
ground
to
apical
meriste
m
Diam
of
seedli
ng
measur
ed in
year
XXXX
at the
widest
axis
of the
base
of the
stem,
for
all
seedli
ngs
>=10
cm in
height
Predomi
nant
substra
te upon
which
the
seeling
is
growing
in year
XXXX
Height
of palm
stem in
year
XXXX as
measured
from the
ground
to the
top of
the stem
between
the last
pair of
leaf
scars
Diamete
r as
measure
d in
year
XXXX at
height
130 cm
Diameter
as
measured
in year
XXXX at
the top of
the palm
stem or
130 cm,
whichever
is lower
Comments
in year
XXXX
indicatin
g a
variety
of
additiona
l details
about the
seedling,
including
why some
data are
absent
Phenology
trap number
with which
each
seedling
subplot is
associated.
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UNIT
PRECISIO
N
NA
NA
NA
NA
NA
NA
NA
.01
RANGE OR
LIST OF
VALUES
1-120
1.1,
1.2,
1.3C…1
20.1,
120.2,
120.3
A, B or
C
>=1
DATA
TYPE
MISSING
DATA
CODES
Integer
Numeri
c
None
Alphabet
ic
None
Numeric
Date
Alphabetic
None
blank
“UNKSPP”
or blank
None
NA
NA
NA
NA
NA
NA
cm
.01
cm
.01
NA
NA
cm
.01
cm
.01
A, D,
NF, or N
>=10
>0
>0
>=130
Alphabet
ic
blank
Numeric
Numeri
c
Blank
BS=Bare
Soil,
DW=Dead
Wood,
L=Leave
s,
LW=Live
Wood,
R=Rock
Numeric
Numeric
Blank
Blank
Blank
cm
.01
NA
Numeric
Numeric
Blank
Blank
Alphanume
ric
blank
* The species list can be downloaded at http://luq.lternet.edu/data/treecode.html
Table 2. Key to the variable ‘comments’ in the Luquillo seedling dynamics Data Set
ABBREVIATION
(as it appears in the data file)
D130
LVS
SP or SPP
TCODS
TCOG
TCOGAR
DEFINITION OF VARIABLE
Diameter (in cm) @ 130 cm height
Leaves
Species
Tag collected on dead stem
Tag collected on ground
Tag collected on ground and reattached
ADDITIONAL NOTES:
Values of the variable „sp‟ include several six-letter codes that represent identification to levels above species. Examples include
“UNKSPP?” for complete unknowns, “VINESP” for unknown lianas, and “MYRSPP” for the genus Myrcia. A key to these codes is
included in the species file that can be downloaded at http://luq.lternet.edu/data/treecode.html
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Publications based on the Luquillo seedling dynamics data set include the following:
Comita, L. S. , J. Thompson, M. Uriarte, I. Jonckheere, C. D. Canham, and J. Zimmerman. 2010. Interactive effects of land use history and natural
disturbance on seedling dynamics in a subtropical forest. Ecological Applications 20: 1270-1284.
Comita, L. S. , M. Uriarte, J. Thompson, I. Jonckheere, C. D. Canham, and J. Zimmerman. 2009. Abiotic and biotic neighborhood determinants of
seedling survival in a hurricane-impacted forest. Journal of Ecology 97: 1346–1359.
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