uid=HFR,o=lter,dc=ecoinformatics,dc=org
all
public
read
doi:10.6073/pasta/7a2a131b52fd6515abb5edbe09b60acc
Barre Woods Soil Warming Experiment at Harvard Forest since 2001
Serita
Frey
https://orcid.org/0000-0002-9221-5919
Jerry
Melillo
Melissa
Knorr
https://orcid.org/0000-0002-8365-7918
Researcher
2024
English
Two of the major results of our original soil warming study were that: (1) warming stimulated the decay of a labile soil carbon pool; and (2) it also increased the availability of inorganic nitrogen to plants. Because of the small size of the original warming plots an important question we have not been able to answer conclusively is: Has the increase in available nitrogen led to an increase in carbon storage in the vegetation? And if yes, how much? In a systems context an additional question is: What is the balance between the carbon lost from the soil and the carbon stored in the vegetation in response to soil warming?
We are now addressing these important questions with a new warming experiment in the Barre Woods area of the Harvard Forest. The Barre Woods site was chosen because of its similarities to the Prospect Hill site - stand age, tree species composition, and soil type. There is no evidence of a plow horizon at the Barre Woods site, though surrounding stone walls indicate past use as pastureland. Historical records indicate the site was destroyed during the 1938 hurricane and then regrew naturally.
During the summer and fall of 2001 we buried 3.4 miles of heating cable in a 30 x 30m plot. Cables were buried at a 10cm depth, spaced 20cm apart. A second 30 x 30m area was delineated to serve as the control plot. Results from the original soil warming experiment confirmed that the soil disturbance associated with the installation of heating cables has had no effect on soil temperatures and only minor and variable impacts on soil moisture.
In April 2002, we began a one-year period of baseline measurements before turning on the heat in the new megaplot. These measurements included nitrogen mineralization, trace gas fluxes (CO2, CH4, N2O), tree growth (dendrometer bands), an understory species survey, canopy foliage analysis (C:N, NIR), and lysimetry. Thermistors were installed in both plots to begin tracking soil temperatures. The baseline measurements have confirmed that there are no significant differences between the two plots for key ecosystem processes prior to the initiation of the warming manipulation.
We will turn on the power in April 2003 to begin the "manipulation phase" of this study. From this study, we expect to determine whether or not warming results in the movement of nitrogen from the soil to the trees and to learn how this movement affects the net carbon balance of the ecosystem.
carbon
carbon dioxide
climate change
methane
nitrogen
nitrogen mineralization
nitrous oxide
soil moisture
soil respiration
soil temperature
soil warming
LTER controlled vocabulary
inorganic nutrients
disturbance
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=hf018
Slab City Tract (Harvard Forest). Coordinates based on WGS84 datum.
-72.18
-72.18
+42.48
+42.48
2001
2021
genus
Acer
species
rubrum
red maple
species
saccharum
sugar maple
genus
Betula
species
alleghaniensis
yellow birch
species
lenta
black birch
genus
Fraxinus
species
americana
white ash
genus
Pinus
species
strobus
white pine
genus
Quercus
species
rubra
red oak
species
velutina
black oak
genus
Tsuga
species
canadensis
hemlock
ongoing
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
The soil in the heated plot was warmed using the buried heating cable method. Heated and control plot temperatures were evaluated on 10 minute intervals by a datalogger, and the heating cables turned on or off accordingly to maintain a difference between the heated and control plot of 5 degrees C. Heated and control plot temperature moisture were recorded on four hour intervals from 2003-2008, and on hourly intervals from 2009 on.
Soil respiration was measured by placing chamber lids over permanent collars installed in the plots for 15 minutes and sampling the headspace gas at 5 minute intervals. CO2 was measured for the duration of the experiment to date, and CH4 and N2O were measured from 2003-2007. CO2 sample concentrations were measured with an infrared gas analyzer, and CH4 and NO2 sample concentrations were measured by gas chromatography. Fluxes were calculated based on the changes in concentrations over the incubation period. Soil temperatures were measured at 2 and 4cm at the time of each gas sampling. Soil moisture measurements were conducted using gravimetric techniques for the first year of the study and by automated time domain reflectometry (TDR) starting in 2003.
Net N mineralization and nitrification were measured for the forest floor and mineral soil using an on-site buried bag incubation. Incubations were for 5 weeks, April- November, and for 5 months through the winter. Initial samples were collected and analyzed for extractable (2N KCl, 48 hours) NH4+ and NO3- content. The same analysis was carried out on the incubated samples. The difference in total mineral N content between initial and incubated soils is the net mineralization rate.
Concentrations of inorganic N in water leaching below the rooting zone were measured using high-tension lysimetry. Soil water samples were collected from 6 porous cup lysimeters per plot, monthly, although in some months no sample was recovered from some or all lysimeters. Lysimeters were installed at a depth of 50 cm and evacuated to ~15 in Hg 24 h before sampling. Samples were frozen until they were analyzed for NH4+ and NO3-.
Tree growth was quantified using dendrometer bands on all trees greater than 9cm DBH. Measurements were made monthly during the growing season.
Canopy chemistry was evaluated (preferentially sun leaves) at the height of the growing season. Leaves were sampled by shotgun in July or August. Analyses were done for C, N (by CHN analysis), cellulose and lignin (using NIR), 13C and 15N (stable isotope mass spectroscopy).
Spring budbreak was measured by visually estimating for each tree the percentage of its leaves that had emerged from their buds.
Litterfall was collected each fall from permanent baskets installed in the plots. Wire baskets dispersed throughout the plots were used from 2003-2009; laundry baskets clustered in the center of the plots were used from 2006-present.
Water holding capacity was measured as field capacity; the mass of water the soil can retain against gravity drainage. Soil samples were saturated in water for 24 hours in mesh-bottomed tubes, and then placed on a metal grate and allowed to drain for another 24 hours. After draining, the water content of the soil was measured gravimetrically (soil samples were weighed, dried in an oven at 105 C for 48 hours, then reweighed).
SOM content was measured by combustion in a muffle furnace at 550 C for 4 hours. Dry soil samples were weighed, combusted, and then reweighed.
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.
hf018-01-trace-gas.csv
trace gas (pre-treatment)
hf018-01-trace-gas.csv
41076
8d8043a813c9d6af34b21dc5f7852e63
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-01-trace-gas.csv
date
collection date
YYYY-MM-DD
NA
missing value
year
year
YYYY
1 year
NA
missing value
month
month
month
NA
missing value
day
day
day
NA
missing value
treatment
treatment
treatment
NA
missing value
plot
plot number
plot number
NA
missing value
ch4
ch4 flux
milligramPerMeterSquaredPerHour
0.000000001
real
NA
missing value
n2o
n2o flux
milligramPerMeterSquaredPerHour
0.000000001
real
NA
missing value
temp2
soil temperature at 2 cm depth
celsius
0.01
real
NA
missing value
temp5
soil temperature at 5 cm depth
celsius
0.01
real
NA
missing value
564
hf018-02-canopy-foliage.csv
canopy foliage (pre-treatment)
hf018-02-canopy-foliage.csv
3727
718997afb6f873723d2d80fc9c63dde8
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-02-canopy-foliage.csv
tree
tree ID
tree ID
NA
missing value
date
collection date
YYYY-MM-DD
NA
missing value
species
species name
species name
NA
missing value
plot
treatment code
c
control
h
heated
NA
missing value
n_per
% nitrogen
number
0.01
real
NA
missing value
lignin_per
% lignin
number
0.01
real
NA
missing value
cellulose_per
% cellulose
number
0.01
real
NA
missing value
94
hf018-03-soil-temp.csv
soil temperature
hf018-03-soil-temp.csv
9942908
84f98e8a9ad118fafea26ee47a70b80c
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-03-soil-temp.csv
datetime
date and time
YYYY-MM-DDThh:mm
NA
missing value
doy
Julian day
nominalDay
1
whole
NA
missing value
year
year
YYYY
NA
missing value
time
time
time
NA
missing value
ctrl_av
average soil temperature Control plot
celsius
0.01
real
NA
missing value
p1_av
average soil temperature Block 1 Heated Plot
celsius
0.01
real
NA
missing value
p2_av
average soil temperature Block 2 Heated Plot
celsius
0.01
real
NA
missing value
p3_av
average soil temperature Block 3 Heated Plot
celsius
0.01
real
NA
missing value
p4_av
average soil temperature Block 4 Heated Plot
celsius
0.01
real
NA
missing value
p5_av
average soil temperature Block 5 Heated Plot
celsius
0.01
real
NA
missing value
p6_av
average soil temperature Block 6 Heated Plot
celsius
0.01
real
NA
missing value
p7_av
average soil temperature Block 7 Heated Plot
celsius
0.01
real
NA
missing value
p8_av
average soil temperature Block 8 Heated Plot
celsius
0.01
real
NA
missing value
p9_av
average soil temperature Block 8 Heated Plot
celsius
0.01
real
NA
missing value
p10_av
average soil temperature Block 10 Heated Plot
celsius
0.01
real
NA
missing value
105609
hf018-04-soil-moisture.csv
soil moisture
hf018-04-soil-moisture.csv
11200685
c3fa8bd8a769e191d09a6e7af10b2576
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-04-soil-moisture.csv
datetime
date and time
YYYY-MM-DDThh:mm
NA
missing value
year
year
YYYY
NA
missing value
doy
Julian day
nominalDay
1
whole
NA
missing value
time
time
time
NA
missing value
tdr1
soil moisture TDR probe 1 in the Heated Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr2
soil moisture TDR probe 2 in the Heated Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr3
soil moisture TDR probe 3 in the Heated Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr4
soil moisture TDR probe 4 in the Heated Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr5
soil moisture TDR probe 5 in the Heated Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr6
soil moisture TDR probe 6 in the Heated Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr7
soil moisture TDR probe 1 in the Control Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr8
soil moisture TDR probe 2 in the Control Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr9
soil moisture TDR probe 3 in the Control Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr10
soil moisture TDR probe 4 in the Control Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr11
soil moisture TDR probe 5 in the Control Plot (%VWC)
dimensionless
0.01
real
NA
missing value
tdr12
soil moisture TDR probe 6 in the Control Plot (%VWC)
dimensionless
0.01
real
NA
missing value
probeset
set of soil moisture probes
0
original set of soil moisture probes installed in 2003
1
set of replacement probes installed in control plot in 2016 (original probes retained in heated plot)
NA
missing value
108715
hf018-05-lysimeter.csv
lysimeter
hf018-05-lysimeter.csv
25205
9ce77472250deffa14285e59239ff67c
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-05-lysimeter.csv
date
collection date
YYYY-MM-DD
NA
missing value
year
year
YYYY
NA
missing value
month
month
month
NA
missing value
day
day
day
NA
missing value
plot
Plot ID
Plot ID
NA
missing value
treatment
treatment
C
control plot
H
heated plot
NA
missing value
nh4
Ammonium
milligramsPerLiter
0.01
real
NA
missing value
no3
Nitrate
milligramsPerLiter
0.01
real
NA
missing value
725
hf018-06-nmin.csv
nitrogen mineralization
hf018-06-nmin.csv
88956
69198f35d8bb237ad3d7fa46a09a541f
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-06-nmin.csv
year
year
YYYY
NA
missing value
month
month
month
NA
missing value
treatment
treatment
c
control plot
h
heated plot
NA
missing value
plot
plot ID
plot ID
NA
missing value
sum_ion
NH4 + NO3 (kgN/ha/month)
kilogramsPerHectarePerMonth
0.0001
real
NA
missing value
nh4
ammonification rate (kgN/ha/monh)
kilogramsPerHectarePerMonth
0.0001
real
NA
missing value
no3
nitrification rate (kgN/ha/month)
kilogramsPerHectarePerMonth
0.0001
real
NA
missing value
3060
hf018-07-soil-respiration.csv
soil respiration
hf018-07-soil-respiration.csv
465529
72f4ee3dc7166aad7aa7cf866e8d6a49
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-07-soil-respiration.csv
datetime
collection date and time
collection date and time
NA
missing value
date
collection date
YYYY-MM-DD
NA
missing value
year
year
YYYY
NA
missing value
month
month
month
NA
missing value
day
day
day
NA
missing value
time
time
hh:mm
NA
missing value
treatment
treatment code
C
control plot
H
heated plot
NA
missing value
plot
subplot within the megaplot
subplot within the megaplot
NA
missing value
co2
CO2 flux in mg C m-2 h-1
milligramPerMeterSquaredPerHour
0.01
real
NA
missing value
cm2
soil temperature at 2 cm depth
celsius
0.01
real
NA
missing value
cm4
soil temperature at 4 cm depth
celsius
0.01
real
NA
missing value
moisture
soil moisture (% volumetric moisture content)
dimensionless
0.001
real
NA
missing value
measurement
measurement type
Li8100-a
automatic LI-COR measurement
static
static chamber gas syringe measurement
NA
missing value
5629
hf018-08-dendrology.csv
dendrology
hf018-08-dendrology.csv
1241536
f1c50346005ce2bd57c0a6f2620f41dd
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-08-dendrology.csv
treeid
unique identification number assigned to each tree in
experiment
unique identification number assigned to each tree in experiment
NA
missing value
date
date
YYYY-MM-DD
NA
missing value
species
species code
ACPE
Acer pensylvanicum, striped maple
ACRU
Acer rubrum, red maple
ACSA
Acer saccharum, sugar maple
ACSP
Acer species, unidentified maple
BEAL
Betula alleghaniensis, yellow birch
BELE
Betula lenta, black birch
BEPA
Betula papyrifera, paper birch
BEPO
Betula populifolia, gray birch
BESP
Betula species, unidentified birch
CADE
Castanea dentata, american chestnut
FAGR
Fagus grandifolia, american beech
FRAM
Fraxinus americana, white ash
PIST
Pinus strobus, white pine
POGR
Populus grandidentataa, bigtooth aspen
PRSE
Prunus serotina, black cherry
QUAL
Quercus alba, white oak
QURU
Quercus rubra, red oak
QUSP
Quercus species, unidentified oak
QUVE
Quercus velutina, black oak
TSCA
Tsuga canadensis, eastern hemlock
NA
missing value
plot
plot
B
Wide buffer zone around plots
Be
Portion of buffer zone within 15 meters of an edge
Bh
Portion of buffer zone within 10 meters of heated plot
Bhe
Portion of buffer zone both within 10 meters of heated plot and 15 meters of an edge
C
Control
H
Heated
S1
Supplemental control plot 1
S2
Supplemental control plot 2
S3
Supplemental control plot 3
S4
Supplemental control plot 4
NA
missing value
subplot
5x5 meter subplot within the C or H plot
5x5 meter subplot within the C or H plots
NA
missing value
dbh
diameter at breast height
centimeter
0.01
real
NA
missing value
33382
hf018-09-litterfall.csv
litterfall
hf018-09-litterfall.csv
51598
bb844d6d1f3e8bb0b50ece9a30d0e949
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-09-litterfall.csv
year
year
YYYY
1 year
NA
missing value
treatment
plot
C
control
H
heated
NA
missing value
species
species code
ACPE
Acer pensylvanicum, striped maple
ACRU
Acer rubrum, red maple
ACSA
Acer saccharum, sugar maple
BESP
Betula species, unidentified birch
CADE
Castanea dentata, american chestnut
FAGR
Fagus grandifolia, american beech
FRAM
Fraxinus americana, white ash
OTHER
other
POGR
Populus grandidentataa, bigtooth aspen
PRSE
Prunus serotina, black cherry
QUAL
Quercus alba, white oak
QURU
Quercus rubra, red oak
UNKN
unknown (mostly unidentifiable fragments)
NA
missing value
basket_num
unique identification number of litter collection
basket
unique identification number of litter collection basket
NA
missing value
basket_type
type of litter basket
WB
wire basket (capture area 0.3215 m2)
LB
laundry basket (capture area 0.2145 m2)
NA
missing value
mass
total dry weight of litterfall captured
gram
0.01
real
NA
missing value
2127
hf018-10-foliage-chemistry.csv
foliage chemistry
hf018-10-foliage-chemistry.csv
46466
9a27e1ddce83da65c2f2ec4e054327b2
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-10-foliage-chemistry.csv
year
year
YYYY
1 year
NA
missing value
treeid
unique identification number assigned to each tree in
experiment
unique identification number assigned to each tree in experiment
NA
missing value
species
species code
ACRU
Acer rubrum, red maple
ACSA
Acer saccharum, sugar maple
BEAL
Betula alleghaniensis, yellow birch
BEPO
Betula populifolia, gray birch
BESP
Betula species, unidentified birch
FRAM
Fraxinus americana, white ash
QURU
Quercus rubra, red oak
QUVE
Quercus velutina, black oak
TSCA
Tsuga canadensis, eastern hemlock
NA
missing value
treatment
plot
H
Heated
C
Control
NA
missing value
n_per
weight percent nitrogen
dimensionless
0.01
real
NA
missing value
c_per
weight percent carbon
dimensionless
0.01
real
NA
missing value
c_n
molar carbon to nitrogen ratio
dimensionless
0.01
real
NA
missing value
d13c
d13C, o/oo vs. PDB
dimensionless
0.01
real
NA
missing value
d15n
d15N, o/oo vs. air
dimensionless
0.01
real
NA
missing value
p_per
weight percent phosphorus
dimensionless
0.00000001
real
NA
missing value
n_p
molar nitrogen to phosphorus ratio
dimensionless
0.000000001
real
NA
missing value
816
hf018-11-budbreak.csv
spring budbreak
hf018-11-budbreak.csv
307944
012da97417a5f1a111d068db12c325b6
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-11-budbreak.csv
date
collection date
YYYY-MM-DD
NA
missing value
tree
unique identification number assigned to each tree in
experiment
unique identification number assigned to each tree in experiment
NA
missing value
plot
treatment
C
Control
H
Heated
NA
missing value
species
species code
ACPE
Acer pensylvanicum, striped maple
ACRU
Acer rubrum, red maple
ACSA
Acer saccharum, sugar maple
BEAL
Betula alleghaniensis, yellow birch
BELE
Betula lenta, black birch
BEPA
Betula papyrifera, paper birch
BEPO
Betula populifolia, gray birch
CADE
Castanea dentata, american chestnut
FRAM
Fraxinus americana, white ash
QUAL
Quercus alba, white oak
QURU
Quercus rubra, red oak
QUVE
Quercus velutina, black oak
NA
missing value
year
year
YYYY
1 year
NA
missing value
doy
day of year (Julian day)
nominalDay
1
natural
NA
missing value
budbreak
visually estimated percentage of buds from which leaves have emerged and
unfolded, to the nearest 10%
dimensionless
1
whole
NA
missing value
8867
hf018-09-litter-chemistry.csv
litter chemistry
hf018-12-litter-chemistry.csv
57363
e62e578dc004ae51dba96355ca8ada2c
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-12-litter-chemistry.csv
year
year
YYYY
1 year
NA
missing value
species
species code
ACRU
Acer rubrum, red maple
ACPE
Acer pensylvanicum, striped maple
ACSA
Acer saccharum, sugar maple
ACSP
Acer species, unidentified maple
BEAL
Betula alleghaniensis, yellow birch
BELE
Betula lenta, black birch
BESP
Betula species, unidentified birch
FRAM
Fraxinus americana, white ash
CADE
Castanea dentata, american chestnut
FAGR
Fagus grandifolia, american beech
POGR
Populus grandidentataa, bigtooth aspen
UNKN
unknown (mostly unidentifiable fragments)
PIST
Pinus strobus, white pine
PRSE
Prunus serotina, black cherry
QUAL
Quercus alba, white oak
QURU
Quercus rubra, red oak
QUSP
Quercus species, unidentified oak
NA
missing value
treatment
plot
C
control
H
heated
NA
missing value
basket_num
unique identification number of litter collection
basket
unique identification number of litter collection basket
NA
missing value
basket_type
type of litter basket
WB
wire basket (capture area 0.3215 m2)
LB
laundry basket (capture area 0.2145 m2)
NA
missing value
c_per
weight percent carbon of litter
dimensionless
0.001
real
NA
missing value
n_per
weight percent nitrogen of litter
dimensionless
0.001
real
NA
missing value
c_n
molar C:N ratio of litter
dimensionless
0.000000001
real
NA
missing value
p_per
weight percent phosphorus
dimensionless
0.00000001
real
NA
missing value
n_p
molar nitrogen to phosphorus ratio
dimensionless
0.000000001
real
NA
missing value
1338
hf018-13-whc.csv
water holding capacity
hf018-13-whc.csv
5194
257a5d5b083be37cb26543a38dcf8204
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p01/hf018/hf018-13-whc.csv
date
sampling date
YYYY-MM-DD
NA
missing value
plot
plot
Control
control plot
Heated
heated plot
NA
missing value
subplot
5 x 5 meter subplot within main plots; 1-36
5 x 5 meter subplot within main plots; 1-36
NA
missing value
horizon
horizon
Organic
organic
Mineral
mineral
NA
missing value
som
soil organic matter content; g organic matter dry weight
gram
0.001
real
NA
missing value
whc
soil water holding capacity; g water at capacity
gram
0.0001
real
NA
missing value
123
plot
soil
long-term measurement
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf005
milligramPerMeterSquaredPerHour
kilogramsPerHectarePerMonth