Supplementary Information
The previously published estimates of the anuual Net Ecosystem Exchange of CO2(NEE) used to create Figure 1 in the main text are shown in
Table S1. These sites were initially selected from among Ameriflux sites with at least five site-years of available data, though sites were included
in the table even if less than five years of reported estimates of NEE were recovered in the literature. In some cases, data were digitized from
graphical displays. The ecosystem type variable indicates: 1 = agricultural field, 2 = grassland or shrubland, 3 = Evergreen forests, 4 = Deciduous
Forest, and 5 = wetland or march. NEE is given in units of g C m-2 y-1.
Site Name
Site
Code
State
Latitude
(oN)
Longitude
(oW)
Type
Study
period
Min NEE
Max NEE
Mean NEE
Reference
ARM SGP Main
ARM
OK
36.6
97.5
2
2003-2007
-128
75
-134
Fischer et al (2007),
Gilmanov et al. (2013)
Sioux Falls Portable
SFP
SD
43.2
96.9
2
2008-2011
-374
-121
-230
Gilmanov et al. (2013)
Bartlett
BAR
NH
41.1
72.3
4
2005-2011
-425
-100
-235
Jenkins et al., (2007),
Keenan et al. (2013)
Bondville
Bo1
IL
40.0
88.3
2
1997-2003
-575
-325
-442
Bernacchi et al. (2005),
Gilmanov et al. (2013)
Brooks Field Site 1
Br1
IA
42.0
93.7
2
2004-2004
-534
-360
-466
Brooks Field Site 2
Br3
IA
42.0
93.7
2
2004-2007
-122
62
-13
Hernadez-Ramirez et
al. (2011)
Hernadez-Ramirez et
al. (2011)
Cedar Bridge
Ced
NJ
39.8
74.4
3
2005-2007
-204
-17
-127
Clark et al. (2010)
Duke Old Field
DK1
NC
36.0
79.1
1
2001-2005
-40
60
8
Stoy et al. (2006)
Duke Hardwood Forest
DK2
NC
36.0
79.1
4
2001-2008
-602
-267
-402
This study
Duke Pine Plantation
DK3
NC
36.0
79.1
3
2001-2008
-712
-173
-506
This study
Florida Everglades Marsh (long)
Elm
FL
25.6
80.8
5
2008-2009
-78
-11
-45
Jimenez et al. (2012)
Florida Everglades Marsh (short)
Esm
FL
25.4
80.6
5
2008-2009
8
80
44
Jimenez et al. (2012)
Flagstaff Managed Forest
Fmf
AZ
35.1
111.7
3
2006-2007
-118
51
-34
Dore et al. (2010)
Flagstaff Unmanaged Forest
Fuf
AZ
35.1
111.8
3
2006-2007
-162
-58
-110
Dore et al. (2010)
Flagstaff Wildfire
Fwf
AZ
35.4
111.8
1
2006-2007
45
109
77
Dore et al. (2010)
Fort Peck
FPE
MT
48.3
105.1
1
2000-2002
-146
44
-51
Gilmanov et al. (2013)
Site Name
Site
Code
State
Latitude
(oN)
Longitude
(oW)
Type
Study
period
Min NEE
Max NEE
Mean NEE
Reference
Harvard Forest
Ha1
MA
42.5
72.2
4
1992 - 2009
-605
-121
-349
Urbanski et al. (2007),
Keenan et al. (2013)
Howland Forest
Ho1
ME
45.2
68.8
3
1997-2005
-270
-130
190
Richardson et al.
(2011)
Kennedy Space Center Slash Pine
KS1
FL
28.5
80.7
3
2001-2003
-99
-99
-99
Powell et al. (2006)
Kennedy Space Center Scrub Oak
KS2
FL
28.6
80.7
1
2001-2006
-467
-107
-319
Powell et al. (2006)
Lost Creek
Los
WI
46.1
90.0
5
2001-2006
-91
-64
-84
Sulman et al. (2009)
Metolius Second Young Pine
Me3
OR
44.3
121.7
3
2004-2008
-199
-49
-126
Vickets et al. (2011)
Metolius Old Pine
Me4
OR
44.5
121.6
3
2002-2008
-507
-251
-465
Thomas et al. (2009)
Morgan-Monroe State Forest
MMS
IN
39.3
86.4
4
1999-2012
-434
-217
333
Brzostek et al. (2014)
Mary's River Fir Site
MRF
OR
44.7
123.6
3
2006-2011
-694
-305
479
Thomas et al. (2013)
North Carolina Loblolly Pine
NC2
NC
35.8
-77.0
3
2007-2009
-835
-361
-640
Noormets et al. (2010)
Mead Irrigated
Ne1
NE
41.2
96.5
2
2002-2004
-517
-381
-441
Verma et al. (2005)
Mead Irrigated Rotation
Ne2
NE
41.2
96.5
2
2002-2004
-572
48
-354
Verma et al. (2005)
Mead Rainfed
Ne3
NE
41.2
96.4
2
2002-2004
-510
18
-1396
Verma et al. (2005)
Niwot Ridge
NR1
CO
40.0
105.5
3
1999-2009
264
186
218
Scott-Denton et al.
(2013)
Ohio Oak Openings
Oho
OH
41.6
83.8
4
2004-2005
-354
-252
-303
Noormets et al. (2008)
Park Falls
Pfa
WI
46.0
90.3
4
1997-2004
47
186
123
Ricciutto et al. (2008)
Sky Oaks Old
SO2
CA
33.4
116.6
2
1998-2003
-155
207
-32
Luo et al.(2007)
Austin-Cary
SP1
FL
29.7
82.2
3
2001-2005
-192
-154
77
Powell et al. (2006)
Mize
Sp2
FL
29.7
82.2
3
2002-2007
-718
-97
-430
Bracho et al. (2012)
Donalson
SP3
FL
29.8
82.2
3
1998-2007
-818
-491
-667
Bracho et al. (2012)
Tonzi Ranch
TON
CA
38.4
121.0
1
2002-2006
-144
-35
-98
Ma et al. (2007)
Silas Little Experimental Forest
Slt
NJ
39.9
74.6
4
2005-2007
-187
296
1
Clark et al. (2010)
Sylvania
Syl
MI
46.2
89.4
4
2002-2003
-147
-72
-110
Desai et al. (2005)
Vaira Ranch
VAR
CA
38.4
121.0
1
2000
-88
189
38
Ma et al. (2007)
Site Name
Site
Code
State
Latitude
(oN)
Longitude
(oW)
Type
Study
period
Min NEE
Max NEE
Mean NEE
Reference
U. of Michigan Biological Station
UMB
MI
45.6
84.7
4
1999-2003
-199
-44
-137
Gough et al. (2008),
Keenan et al. (2013)
Walker Branch
WBW
TN
36.0
84.3
4
1995-1999
-629
-470
-574
Wilson et al. (2001)
Willow Creek
Wcr
WI
45.8
90.1
4
2002-2003
-490
-438
-464
Desai et al. (2005)
Kendall Grassland
Wkg
AZ
31.7
109.9
1
2004-2007
-98
21
-50
Scott et al. (2010)
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