uid=HFR,o=lter,dc=ecoinformatics,dc=org
all
public
read
doi:10.6073/pasta/6a45cf16a9593a12370c251ae40369b1
Impacts of Phloem Chilling on Mature Red Maples at Harvard Forest 2019
Tim
Rademacher
https://orcid.org/0000-0002-0627-6564
Andrew
Richardson
https://orcid.org/0000-0002-0148-6714
Researcher
Mark
VanScoy
Researcher
2023
English
Whether tree growth is limited by carbon supply or demand is a crucial question due to wide-ranging repercussions for projections of carbon sequestration on land. By temporarily restricting phloem transport using stem chilling, which increases phloem sap viscosity to create local bottlenecks to phloem transport, we created gradients of carbon supply in stems of mature red maples during the first half of the growing season. These carbon supply gradients had clear effects on tree physiology with radial growth in particular varying up to almost seven-fold with carbon supply. Local bulk nonstructural carbon concentrations in stems and roots remained relatively stable, suggesting that they are not rapidly modulated in response to changes in supply and demand. However, phloem and leaf nonstructural carbon accumulated above chilling-induced bottlenecks and were associated with reductions in photosynthetic capacity as well as the advancement of leaf coloration and fall, supporting the idea of within-tree feedbacks reducing carbon supply when supply exceeds demand. Most strikingly, radial growth varied systematically with carbon supply up to almost seven-fold, indicating that growth of red maple during the early growing season is strongly carbon-supply limited.
The code to process these data and reproduce our results is available at https://github.com/TTRademacher/Exp2019Analysis. For more details pertaining to the methods see Rademacher et al. (2021) and contact the investigator.
aboveground biomass
carbohydrates
carbon
maple
respiration
tree growth
tree physiology
tree rings
wood
LTER controlled vocabulary
primary production
LTER core area
Harvard Forest
HFR
LTER
USA
HFR default
This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.
Creative Commons Zero v1.0 Universal
https://spdx.org/licenses/CC0-1.0.html
CC0-1.0
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf421
Prospect Hill Tract (Harvard Forest). Coordinates based on WGS84 datum.
-72.22
-72.22
+42.51
+42.51
340
340
meter
2019
2019
genus
Pinus
species
strobus
complete
Information Manager
Harvard Forest
324 North Main Street
Petersham
MA
01366
USA
(978) 724-3302
hf-im@lists.fas.harvard.edu
Harvard Forest
324 North Main Street
Petersham
MA
01366
USA
(978) 724-3302
(978) 724-3595
https://harvardforest.fas.harvard.edu
All trees were monitored throughout the growing season from the beginning of April to early October. The chilling was switched on from the end of May to early July. During the chilling period we characterised radial growth, stem CO2 efflux, and root, nonstructural carbon content (soluble sugars and starch) for root, phloem, xylem and leaf tissues. Additionally, tree water status was measured throughout the growing season using sap flow sensors and leaf and branch water potential measurements. Finally, leaf phenology was observed in the shoulder seasons and photosynthesis and leaf fluorescence were measured towards the end of the chilling period in early July.
Phloem chilling and temperature monitoring
A cluster of eight mature red maples was divided into four groups of two similar trees in terms of size and canopy status. In the field, one tree of each pair was randomly assigned with a coin flip to a treatment group: control versus chilled. To monitor phloem tempertures we implanted negative temperature coefficient thermistors (2.5 mm diameter, SC30F103V, Amphenol Thermometrics Inc., St. Marys, Pennsylvania, USA) in the phloem at 1.0 and 2.0 m using surgical needles in early May 2019. Copper coil was thereafter wrapped around 30 cm of stem (centered on 1.0 and 2.0 m). The copper was linked to coolant supply loops with one ALPHA2 circulator (Grundfos, Bjerringbro, Denmark) per pair of trees. Chilling to the main supply line was provided by a six ton chiller (Chillking, Bastrop, Texas, USA), which was switched on and off to keep the chilling temperature in the main loop about 0°C. Main loop temperatures were monitored using 20 T_109 thermitors (Campbell Scientific, Edmonton, Alberta, Canada), which were calibrated in an ice-bath prior to deployment. Piping and chilling collars were insulated to reduce heat loss to the environments and covered in radiative barriers. The chilling was switched on and off on the 29 May 2019 and 20 Jul 2019, respectively.
Wood formation and anatomy
Tree-ring growth was characterised from stem microcores collected at four sampling heights on the stem with a Trephor (Rossi et al., 2006) starting in the beginning of April and ending in early October with one follow-up sample collected on the 4 Aug 2020. Ring widths were measured using the self-developed Wood Image Analysis and Database platform on microsection images captured using a digital slide-scanner (Zeiss Axio Scan.Z1, Germany) with a resolution of roughly 1.5 pixels per micrometer.
Stem respiration
Starting in April, an infrared gas analyser (LI-820, LI-COR, Lincoln, Nebraska, USA) with a circulating pump was attached to stem respiration chambers using a lid with two ports to constantly circulate air through the closed system (Carbone et al., 2019). The chamber CO2 concentration was measured at 1 Hz for at least one minute, once it had stabilised to ambient values. The raw stem CO2 efflux and uncertainties were estimated using the RespChamberProc package (http://r-forge.r-project.org/projects/respchamberproc/) as developed by Perez-Priego et al. (2015).
Nonstructural carbon
Soluble sugar and starch concentrations in coarse root, phloem, xylem, and leaf tissues were determined from samples collected regularly throughout the growing season. Coarse root (at least 20 cm below the root collar) and stem samples were collected using a 5.15 mm increment borer (Haglӧf Company Group, Långsele, Sweden). Stem cores were divided into phloem and the first centimetre of xylem adjacent to the phloem with a scalpel. About 40 mg of finely ground and dried powder for all tissue, tree and sampling date combinations was analysed following the protocol by Chow and Landhäusser (2004) using a colourimetric assay with phenol-sulphuric acid after ethanol extraction. Each batch of 40 samples included at least seven blanks and nine laboratory control standards of either red oak stem wood (Harvard Forest, Petersham, Massachusetts, USA) or potato starch (Sigma Chemicals, St. Louis, Missouri, USA). Absorbance for each batch were calibrated using a 1:1:1 glucose:fructose:galactose (Sigma Chemicals, St Louis, Missouri, USA) standard curve values using the self-developed R-package NSCprocessR (https://github.com/ttrademacher/NSCprocessR) to converted sample absorbances to concentrations in % dry weight and uncertainties.
Water potential and sap flow
Pre-dawn needle and branch water potential were measured biweekly with a pressure chamber (Model 600, PMS Instruments, Albany, Oregon, USA) throughout the growing season.
For each measurement, the canopy of two adjacent trees (one chilled and one control tree) was reached with a canopy lift, two branch tips and two leaves per tree were severed with a razor blade. Within seconds of harvesting each sample, water potential was determined after re-cutting the tissue on a cutting board to have a clean edge and before moving onto the next sample. Observed needle and branch water potential did not differ among treatments during the duration of the experiment or in the remaining growing season. In addition to the leaf and branch water potential, we installed three needle heat-pulse sap flow sensors (East 30, Pullman, Washington, USA) in the early growing season on all trees (chilled and control trees) at a stem height of 1.5 m, which was between the two chilling collars for chilled trees. These sensors measure temperature at 5, 17.5 and 30 mm on the first and third needle and use the temperature differential before and after a heat pulse originating in the middle needle to estimate sap flow velocity at the three depths.
Leaf phenology observations
Leaf phenology was observed starting in the fall of 2018 and finishing in the fall of 2019 after the chilling had concluded. We followed the protocol by O’Keefe (2019). Using binoculars we visually observed the crown of each tree to determine the dates of bud burst, leaf elongation, leaf coloration and leaf fall.
Photosynthesis and leaf fluorescence
Towards the end of the chilling period, we also measured leaf photosynthesis and fluorescence from a canopy lift. Each set of measurements was performed simultaneously on one tree from the control group and one tree from the chilled group. Over a period of ten days we measured instantaneous photosynthetic rates, light response curves, and A/Ci curves using a LiCOR-6400 (Lincoln, Nebraska, USA). Directly after each measurement, we cut the leaf at the petiole and measured chlorophyll fluorescence using an OS-30P (Opti-Sciences, Hudson, New Hampshire, USA). Leaves were subsequently wrapped in aluminium foil and kept in a cooler with ice to dark-adapt. At the end of the day, we re-measured dark-adapted leaf fluorescence, weighed the leaves, scanned (3200 dpi, V600 Epson Perfection) and oven-dried them at 60°C for 24 hours, and weighed them again.
For more details pertaining to the methods see Rademacher et al. (2021) or contact the lead investigator.
Harvard Forest Long-Term Ecological Research
Harvard Forest
324 North Main Street
Petersham
MA
01366
USA
(978) 724-3302
(978) 724-3595
https://harvardforest.fas.harvard.edu
https://ror.org/059cpzx98
pointOfContact
The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts.
National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210.
hf421-01-nsc.csv
nonstructural carbon concentrations
hf421-01-nsc.csv
140141
441c3fa38c6ed51aab00591a9b4aa4c7
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-01-nsc.csv
sample.type
type of sample
type of sample
rc.lab.number
internal identification number for the Richardson and Carbone Lab
internal identification number for the Richardson and Carbone Lab
sample.id
sample identifier
sample identifier
tissue
tissue type
tissue type
batch.id
batch identifier
batch identifier
sample.location
location where sample was collected
location where sample was collected
date.of.sample.collection
date the sample was collected
date the sample was collected
date.of.sugar.analysis
date the sugar extraction and anaylsis was done
date the sugar extraction and anaylsis was done
date.of.starch.analysis
date the starch extraction and analysis was done
date the starch extraction and analysis was done
mass.of.empty.tube
mass of empty tube
gram
1e-04
real
NA
missing value
mass.of.tube.and.sample
mass of tube with the sample
gram
1e-04
real
NA
missing value
absorbance490.1
first absorbance value read at 490 nm
dimensionless
0.001
real
NA
missing value
absorbance490.2
second absorbance value read at 490 nm
dimensionless
0.001
real
NA
missing value
absorbance490.blank
absorbance value at 490 nm for the blank
dimensionless
0.001
real
NA
missing value
absorbance525.1
first absorbance value read at 525 nm
dimensionless
0.001
real
NA
missing value
absorbance525.2
second absorbance value read at 525 nm
dimensionless
0.001
real
NA
missing value
dilution.factor.sugar
factor by which the sugar extract was diluted
dimensionless
0.001
real
NA
missing value
volume.sugar
volume of the sugar extract
milliliter
0.001
real
NA
missing value
dilution.factor.starch
factor by which the starch extract was diluted
dimensionless
0.001
real
NA
missing value
volume.starch
volume of the starch extract
milliliter
0.001
real
NA
missing value
comments
comments
comments
1038
hf421-02-respiration.csv
stem respiration
hf421-02-respiration.csv
313640
f1517b4ead7b4f92415e6c3677ba67b9
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-02-respiration.csv
file
name of the raw data file
name of the raw data file
study
name of the study group
name of the study group
treatment
treatment group
1
control
4
double compressed
5
chilled
tree
tree identifier
tree identifier
species
tree species
tree species
chamber
chamber identifier
1
0.5 m above the ground
2
1.5 m above the ground
3
2.5 m above the ground
chamber.volume
volume of the respiration chamber
cubicMeter
1e-15
real
NA
missing value
chamber.area
stem surface area covered by the chamber
squareMeter
1e-15
real
NA
missing value
datetime
time stamp of when the measurement started
time stamp of when the measurement started
session
identifier for the session of respiration measurements
identifier for the session of respiration measurements
flux.raw
mean respiratory flux from this chamber
micromolePerMeterSquaredPerSecond
1e-15
real
NA
missing value
sd.flux.raw
standard deviation of the respiratory flux from this chamber
micromolePerMeterSquaredPerSecond
1e-15
real
NA
missing value
aic.raw
Akaike Information Criterion of model fitted to respiration curve
dimensionless
1e-15
real
NA
missing value
r2.raw
R2 of fit to the respiration curve after correction for water vapour dilution using atmospheric humidity
dimensionless
1e-15
real
NA
missing value
flux.atm
mean respiratory flux after correction for water vapour dilution using internal humidity from this chamber
micromolePerMeterSquaredPerSecond
1e-15
real
NA
missing value
sd.flux.atm
standard deviation of the respiratory flux after correction for water vapour dilution using atmospheric humidity from this chamber
micromolePerMeterSquaredPerSecond
1e-15
real
NA
missing value
aic.atm
Akaike Information Criterion of model fitted to respiration curve after correction for water vapour dilution using atmospheric humidity
dimensionless
1e-15
real
NA
missing value
r2.atm
R2 of fit to the respiration curve after correction for water vapour dilution using atmospheric humidity
dimensionless
1e-15
real
NA
missing value
flux.int
mean respiratory flux after correction for water vapour dilution using internal humidity from this chamber
micromolePerMeterSquaredPerSecond
1e-15
real
NA
missing value
sd.flux.int
standard deviation of the respiratory flux after correction for water vapour dilution using internal humidity from this chamber
micromolePerMeterSquaredPerSecond
1e-15
real
NA
missing value
aic.int
Akaike Information Criterion of model fitted to respiration curve after correction for water vapour dilution using internal humidity
dimensionless
1e-15
real
NA
missing value
r2.int
R2 of fit to the respiration curve after correction for water vapour dilution using internal humidity
dimensionless
1e-15
real
NA
missing value
ea.pa
atmospheric pressure from the Fisher meteorological station
pascal
1e-15
real
NA
missing value
airt.c
surface air temperature from the Fisher meteorological station
celsius
0.01
real
NA
missing value
soilt1.c
soil temperature at 2.25 cm near the Barn Tower
celsius
0.01
real
NA
missing value
soilt2.c
soil temperature at 6.8 cm near the Barn Tower
celsius
0.01
real
NA
missing value
soilt3.c
soil temperature at 12.85 cm near the Barn Tower
celsius
0.01
real
NA
missing value
soilt4.c
soil temperature at 22.75 cm near the Barn Tower
celsius
0.01
real
NA
missing value
pres.pa
atmospheric barometric pressure from the Fisher Meteorological station
pascal
1
whole
NA
missing value
h2o.ppt.atm
atmospheric humidity from the Fisher meteorological station in parts per thousand
dimensionless
1e-15
real
NA
missing value
h2o.ppt.int
internal atmospheric humidity from the Li-Cor 840 in parts per thousand
dimensionless
1e-15
real
NA
missing value
vwc.daily
daily mean volumetric water content from probes at the Barn Tower
dimensionless
1e-15
real
NA
missing value
vwc1
10-minute mean volumetric water content at 2.25 cm near the Barn Tower
dimensionless
0.001
real
NA
missing value
vwc2
10-minute mean volumetric water content at 6.8 cm near the Barn Tower
dimensionless
0.001
real
NA
missing value
vwc3
10-minute mean volumetric water content at 12.85 cm near the Barn Tower
dimensionless
0.001
real
NA
missing value
vwc4
10-minute mean volumetric water content at 22.75 cm near the Barn Tower
dimensionless
0.001
real
NA
missing value
total.rad
total downwelling shortwave radiation at top of Barn Tower
wattPerMeterSquared
1e-06
real
NA
missing value
diffuse.rad
diffuse downwelling shortwave radiation at top of Barn Tower
wattPerMeterSquared
1e-07
real
NA
missing value
920
hf421-03-water-potential.csv
water potential
hf421-03-water-potential.csv
1592
5e18488b7d23f2af3b38e293335e47b6
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-03-water-potential.csv
date
date of measurement
date of measurement
tree
tree identifier
tree identifier
treatment
treatment
1
control
5
chilled
phi.branch
mean pre-dawn branch water potential out of three measurements
megapascal
0.01
real
"NA"
missing value
phi.leaf
mean pre-dawn needle water potential out of three measurements
megapascal
0.01
real
"NA"
missing value
comments
comments
comments
56
hf421-04-temperature.csv
temperature data
hf421-04-temperature.csv
7149208
6b71d9a2021bba578813c36f031f9a50
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-04-temperature.csv
datetime
date and time of measurement
date and time of measurement
record
number of record
number of record
u.battery
battery voltage of data logger
volt
0.01
real
NA
missing value
t.panel
temperature of data logger
celsius
0.01
real
NA
missing value
t.oak.1p5m
control air temperature at 1.5 m on a neighbouring oak tree
celsius
0.01
real
NA
missing value
t.acer.02.1p0m
phloem temperature underneath the lower chilling collar at 1.0 m on tree 02
celsius
0.01
real
NA
missing value
t.acer.02.2p0m
phloem temperature underneath the lower chilling collar at 2.0 m on tree
celsius
0.01
real
NA
missing value
t.acer.04.1p0m
phloem temperature underneath the lower chilling collar at 1.0 m on tree 04
celsius
0.01
real
NA
missing value
t.acer.04.2p0m
phloem temperature underneath the lower chilling collar at 2.0 m on tree 04
celsius
0.01
real
NA
missing value
t.acer.06.1p0m
phloem temperature underneath the lower chilling collar at 1.0 m on tree 06
celsius
0.01
real
NA
missing value
t.acer.06.2p0m
phloem temperature underneath the lower chilling collar at 2.0 m on tree 06
celsius
0.01
real
NA
missing value
t.acer.07.1p0m
phloem temperature underneath the lower chilling collar at 1.0 m on tree 07
celsius
0.01
real
NA
missing value
t.acer.07.2p0m
phloem temperature underneath the lower chilling collar at 2.0 m on tree 07
celsius
0.01
real
NA
missing value
t.acer.01.1p0m
phloem temperature at 1.0 m on tree 01
celsius
0.01
real
NA
missing value
t.acer.01.2p0m
phloem temperature at 2.0 m on tree 01
celsius
0.01
real
NA
missing value
t.acer.03.1p0m
phloem temperature at 1.0 m on tree 03
celsius
0.01
real
NA
missing value
t.acer.03.2p0m
phloem temperature at 2.0 m on tree 03
celsius
0.01
real
NA
missing value
t.acer.05.1p0m
phloem temperature at 1.0 m on tree 05
celsius
0.01
real
NA
missing value
t.acer.05.2p0m
phloem temperature at 2.0 m on tree 05
celsius
0.01
real
NA
missing value
t.acer.08.1p0m
phloem temperature at 1.0 m on tree 08
celsius
0.01
real
NA
missing value
t.acer.08.2p0m
phloem temperature at 2.0 m on tree 08
celsius
0.01
real
NA
missing value
t.misc1
air temperature at 1.5 m underneath the canopy
celsius
0.01
real
NA
missing value
t.misc2
air temperature at 2.0 m underneath the canopy
celsius
0.01
real
NA
missing value
50370
hf421-05-boundaries.csv
boundaries
hf421-05-boundaries.csv
2869
e900be76382f94ede2b9165e9295aeec
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-05-boundaries.csv
image.name
file name of the image
file name of the image
xDim
image dimension of the x-axis in pixels
dimensionless
1
natural
NA
missing value
yDim
dimension of the y-axis in pixels
dimensionless
1
natural
NA
missing value
img.rotation
necessary rotation before ROI extraction
degree
1
natural
NA
missing value
xMin2018
value at which the 2018 ROI starts on the x-axis in pixels
dimensionless
1
natural
NA
missing value
xMax2018
value at which the 2018 ROI ends on the x-axis in pixels
dimensionless
1
natural
NA
missing value
yMin2018
value at which the 2018 ROI starts on the x-axis in pixels
dimensionless
1
natural
NA
missing value
yMax2018
value at which the 2018 ROI ends on the x-axis in pixels
dimensionless
1
natural
NA
missing value
xMin2019
value at which the 2019 ROI starts on the x-axis in pixels
dimensionless
1
natural
NA
missing value
xMax2019
value at which the 2019 ROI ends on the x-axis in pixels
dimensionless
1
natural
NA
missing value
yMin2019
value at which the 2019 ROI starts on the x-axis in pixels
dimensionless
1
natural
NA
missing value
yMax2019
value at which the 2019 ROI ends on the x-axis in pixels
dimensionless
1
natural
NA
missing value
32
hf421-06-instantaneous-photosynthesis.csv
instantaneous photosynthetic rates
hf421-06-instantaneous-photosynthesis.csv
9539
43dedb79a4d08aebdde321afef06851f
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-06-instantaneous-photosynthesis.csv
study
study
study
tree
tree identifier
tree identifier
treatment
treatment group
treatment group
leaf
leaf identifier
leaf identifier
position
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
date
date of measurement
date of measurement
time
time of measurement
time of measurement
photosynthetic.rate.1
first measurement of instantaneous photosynthetic rate
micromolePerMeterSquaredPerSecond
0.01
real
NA
missing value
photosynthetic.rate.2
second measurement of instantaneous photosynthetic rate
micromolePerMeterSquaredPerSecond
0.01
real
NA
missing value
photosynthetic.rate.3
third measurement of instantaneous photosynthetic rate
micromolePerMeterSquaredPerSecond
0.01
real
NA
missing value
photosynthetic.rate.4
fourth measurement of instantaneous photosynthetic rate
micromolePerMeterSquaredPerSecond
0.01
real
NA
missing value
photosynthetic.rate.5
fifth measurement of instantaneous photosynthetic rate
micromolePerMeterSquaredPerSecond
0.01
real
NA
missing value
fresh.weight
fresh weight of the leaf
milligram
0.001
real
NA
missing value
dry.weight
dry weight of the leaf
milligram
0.001
real
NA
missing value
moisture.content
percent moisture content of the leaf
dimensionless
0.01
real
NA
missing value
comments
comments
study
110
hf421-07-photosynthesis-aci.csv
A/Ci curves
hf421-07-photosynthesis-aci.csv
85187
d945ecd2ccd738c0069c9cabdc5b7963
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-07-photosynthesis-aci.csv
date
date of measurement
date of measurement
record
number of record
number of record
time
time of measurement
time of measurement
position
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
study
study
study
tree
tree identifier
tree identifier
leaf
leaf identifier
leaf identifier
FTime
flow time
second
0.1
real
NA
missing value
photosynthetic.rate
measurement of photosynthetic rate
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
conductance
conductance to H2O
molePerMeterSquaredPerSecond
0.001
real
NA
missing value
ci
intercellular CO2 concentration
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
tr.mmol
transpiration rate
millimolePerMeterSquaredPerSecond
0.001
real
NA
missing value
vpd
vapour pressure deficit based on leaf temperature
kilopascal
0.001
real
NA
missing value
ct.leaf
temperature of leaf thermocouple
celsius
0.001
real
NA
missing value
area
in-chamber leaf area on which the measurement was performed
centimeterSquared
1
whole
NA
missing value
BLC_1
one-side boundary layer conductance
molePerMeterSquaredPerSecond
0.01
real
NA
missing value
StmRat
stomatal ratio estimate
dimensionless
1
whole
NA
missing value
BLCond
total boundary layer conductance
molePerMeterSquaredPerSecond
0.01
real
NA
missing value
t.air
air temperature
celsius
0.001
real
NA
missing value
t.leaf
leaf temperature
celsius
0.001
real
NA
missing value
t.bulk
bulk temperature
celsius
0.001
real
NA
missing value
co2.r
CO2 concentration in the reference cell
micromolePerMole
0.001
real
NA
missing value
co2.s
CO2 concentration in the sample cell
micromolePerMole
0.001
real
NA
missing value
h2o.r
H2O concentration in the reference cell
micromolePerMole
0.001
real
NA
missing value
h2o.s
H2O concentration in the sample cell
micromolePerMole
0.001
real
NA
missing value
rh.r
relative humidity in the reference cell
dimensionless
0.001
real
NA
missing value
rh.s
relative humidity in the sample cell
dimensionless
0.001
real
NA
missing value
flow
flow rate
millimolePerSecond
0.001
real
NA
missing value
par.i
photosynthetically active radiation inside the chamber
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
par.o
photosynthetically active radiation outside the chamber
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
press
atmospheric pressure photosynthetically active radiation inside the chamber
kilopascal
0.001
real
NA
missing value
CsMch
sample CO2 offset
micromolePerMole
0.001
real
NA
missing value
HsMch
sample H2O offset
millimolePerSecond
0.001
real
NA
missing value
StableF
flag whether the feed flow is stable
dimensionless
0.001
real
NA
missing value
BLCslope
slope of the boundary layer conductance of the leaf
dimensionless
0.01
real
NA
missing value
BLCoffst
offset of the boundary layer conductance of the leaf
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
t.air.k
air temperature
kelvin
0.001
real
NA
missing value
t.wall.k
wall temperature
kelvin
0.001
real
NA
missing value
rad
flag whether radians are used for trigonometrics functions
dimensionless
0.001
real
NA
missing value
Tl-Ta
difference in leaf and air temperature
celsius
0.001
real
NA
missing value
CndTotal
total conductance
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
vp_kPa
vapour pressure
kilopascal
0.001
real
NA
missing value
vpd.a
vapour pressure deficit based on air temperature
kilopascal
0.001
real
NA
missing value
CndCO2
CO2 conductance
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
ci.Pa
intercellular CO2 concentration
micromolePerMole
0.001
real
NA
missing value
Ci.Ca
ratio of intercellular over ambient CO2 concentration
micromolePerMole
0.001
real
NA
missing value
299
hf421-08-photosynthesis-light-response.csv
light response curves
hf421-08-photosynthesis-light-response.csv
67858
f7fea3d6d8490667f71979e40bc6cb73
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-08-photosynthesis-light-response.csv
date
date of measurement
date of measurement
record
number of record
number of record
time
time of measurement
time of measurement
position
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
study
study
study
tree
tree identifier
tree identifier
leaf
leaf identifier
leaf identifier
FTime
flow time
second
0.1
real
NA
missing value
photosynthetic.rate
measurement of photosynthetic rate
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
conductance
conductance to H2O
molePerMeterSquaredPerSecond
0.001
real
NA
missing value
ci
intercellular CO2 concentration
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
tr.mmol
transpiration rate
millimolePerMeterSquaredPerSecond
0.001
real
NA
missing value
vpd
vapour pressure deficit based on leaf temperature
kilopascal
0.001
real
NA
missing value
ct.leaf
temperature of leaf thermocouple
celsius
0.001
real
NA
missing value
area
in-chamber leaf area on which the measurement was performed
centimeterSquared
1
whole
NA
missing value
BLC_1
one-side boundary layer conductance
molePerMeterSquaredPerSecond
0.01
real
NA
missing value
StmRat
stomatal ratio estimate
dimensionless
1
whole
NA
missing value
BLCond
total boundary layer conductance
molePerMeterSquaredPerSecond
0.01
real
NA
missing value
t.air
air temperature
celsius
0.001
real
NA
missing value
t.leaf
leaf temperature
celsius
0.001
real
NA
missing value
t.bulk
bulk temperature
celsius
0.001
real
NA
missing value
co2.r
CO2 concentration in the reference cell
micromolePerMole
0.001
real
NA
missing value
co2.s
CO2 concentration in the sample cell
micromolePerMole
0.001
real
NA
missing value
h2o.r
H2O concentration in the reference cell
micromolePerMole
0.001
real
NA
missing value
h2o.s
H2O concentration in the sample cell
micromolePerMole
0.001
real
NA
missing value
rh.r
relative humidity in the reference cell
dimensionless
0.001
real
NA
missing value
rh.s
relative humidity in the sample cell
dimensionless
0.001
real
NA
missing value
flow
flow rate
millimolePerSecond
0.001
real
NA
missing value
par.i
photosynthetically active radiation inside the chamber
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
par.o
photosynthetically active radiation outside the chamber
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
press
atmospheric pressure photosynthetically active radiation inside the chamber
kilopascal
0.001
real
NA
missing value
CsMch
sample CO2 offset
micromolePerMole
0.001
real
NA
missing value
HsMch
sample H2O offset
millimolePerSecond
0.001
real
NA
missing value
StableF
flag whether the feed flow is stable
dimensionless
0.001
real
NA
missing value
BLCslope
slope of the boundary layer conductance of the leaf
dimensionless
0.01
real
NA
missing value
BLCoffst
offset of the boundary layer conductance of the leaf
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
t.air.k
air temperature
kelvin
0.001
real
NA
missing value
t.wall.k
wall temperature
kelvin
0.001
real
NA
missing value
rad
flag whether radians are used for trigonometrics functions
dimensionless
0.001
real
NA
missing value
Tl-Ta
difference in leaf and air temperature
celsius
0.001
real
NA
missing value
CndTotal
total conductance
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
vp_kPa
vapour pressure
kilopascal
0.001
real
NA
missing value
vpd.a
vapour pressure deficit based on air temperature
kilopascal
0.001
real
NA
missing value
CndCO2
CO2 conductance
micromolePerMeterSquaredPerSecond
0.001
real
NA
missing value
ci.Pa
intercellular CO2 concentration
micromolePerMole
0.001
real
NA
missing value
Ci.Ca
ratio of intercellular over ambient CO2 concentration
micromolePerMole
0.001
real
NA
missing value
240
hf421-09-leaf-fluorescence.csv
leaf fluorescence
hf421-09-leaf-fluorescence.csv
45263
76137f724c840577d4d0c4519d0943d4
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p42/hf421/hf421-09-leaf-fluorescence.csv
study
study
study
tree
tree identifier
tree identifier
treatment
treatment group
treatment group
leaf
leaf identifier
leaf identifier
position
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
position in the canopy, which is either “top” for sun-exposed leaves or “bottom” for shade leaves
date
date of measurement
date of measurement
time
time of measurement
time of measurement
Fo.1
first measurement of minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.1
first measurement of maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.1
first measurement of the ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.2
second measurement of minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.2
second measurement of maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.2
second measurement of the ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.3
third measurement of minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.3
third measurement of maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.3
third measurement of the ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.4
fourth measurement of minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.4
fourth measurement of maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.4
fourth measurement of the ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.5
fifth measurement of minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.5
fifth measurement of maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.5
fifth measurement of the ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.dark.1
first measurement of dark-adapted minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.dark.1
first measurement of dark-adapted maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.dark.1
first measurement of the dark-adapted ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.dark.2
second measurement of dark-adapted minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.dark.2
second measurement of dark-adapted maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.dark.2
second measurement of the dark-adapted ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.dark.3
third measurement of dark-adapted minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.dark.3
third measurement of dark-adapted maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.dark.3
third measurement of the dark-adapted ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.dark.4
fourth measurement of dark-adapted minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.dark.4
fourth measurement of dark-adapted maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.dark.4
fourth measurement of the dark-adapted ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
Fo.dark.5
fifth measurement of dark-adapted minimum fluorescence
dimensionless
0.001
real
NA
missing value
Fm.dark.5
fifth measurement of dark-adapted maximum fluorescence
dimensionless
0.001
real
NA
missing value
FvOverFm.dark.5
fifth measurement of the dark-adapted ratio of variable and maximum fluorescence
dimensionless
0.001
real
NA
missing value
fresh.weight
weight of the leaf when collected
gram
0.001
real
NA
missing value
dry.weight
weight of the leaf after oven-drying
gram
0.001
real
NA
missing value
moisture.content
moisture content of the leaf
dimensionless
0.01
real
NA
missing value
comments
comments
comments
200
atmosphere
plot
community
short-term measurement
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf001
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf003
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf347
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf348
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf361
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf422
https://harvardforest.fas.harvard.edu/exist/apps/archives/views/view-item.xql?id=10661
https://github.com/TTRademacher/Exp2019Analysis
https://wiad.science
micromolePerMeterSquaredPerSecond
millimolePerMeterSquaredPerSecond
millimole per second