1. Title: Root Morphology and Architecture Respond to N Addition in Pinus
tabuliformis, West China
2. Authors and addresses
Guoliang Wang1,2, Timothy J. Fahey3, Sha Xue1,2 , Fang liu1
1. Institute of Soil and Water Conservation, Northwest A&F University, Yangling,
Shaanxi Province 712100, P.R. China
2. State Key Laboratory of Soil Erosion and Dryland on Loess Plateau, Institute of
Soil and Water Conservation of CAS and MWR, Yangling, Shaanxi Province
712100, P.R. China
3. Department of Natural Resources, Cornell University, Ithaca, NY 14853, USA
3. Short title: Root Morphology and Architecture Respond to N Addition
Resource 1 Frequency percentage of root numbers in diameter intervals for each order of Pinus
tabuliformis growing in control plots on the Loess Plateau, western China.
Resource 2 Percentage of root number for first to fifth root order of Pinus tabuliformis included in the
five diameter intervals in control plots on the Loess Plateau, China.
Resource 3 Percentage of root biomass for first to fifth root order of Pinus tabuliformis included in the
five diameter intervals in control plots on the Loess Plateau, China.
Resource 4 Diameter divisions (mm) of 75% confidence intervals of root number for first to fifth order
roots of Pinus tabuliformis under different N fertilization treatments on the Loess Plateau, western
China
Resource 5 Critical value of root number between adjacent diameter classes (mm) under different N
fertilization treatments for Pinus tabuliformis on the Loess Plateau, western China
45
0-0.1
0.1-0.2
0.2-0.3
0.3-0.4
0.4-0.5
0.5-0.6
0.6-0.7
0.7-0.8
0.8-0.9
0.9-1.0
1.0-1.1
1.1-1.2
1.2-1.3
1.3-1.4
1.4-1.5
1.5-1.6
1.6-1.7
1.7-1.8
1.8-1.9
1.9-2.0
2.0-2.1
2.1-2.2
2.2-2.3
2.3-2.4
30
0
60
45
30
0
60
45
30
0
60
0-0.1
0.1-0.2
0.2-0.3
0.3-0.4
0.4-0.5
0.5-0.6
0.6-0.7
0.7-0.8
0.8-0.9
0.9-1.0
1.0-1.1
1.1-1.2
1.2-1.3
1.3-1.4
1.4-1.5
1.5-1.6
1.6-1.7
1.7-1.8
1.8-1.9
1.9-2.0
2.0-2.1
2.1-2.2
2.2-2.3
2.3-2.4
45
0-0.1
0.1-0.2
0.2-0.3
0.3-0.4
0.4-0.5
0.5-0.6
0.6-0.7
0.7-0.8
0.8-0.9
0.9-1.0
1.0-1.1
1.1-1.2
1.2-1.3
1.3-1.4
1.4-1.5
1.5-1.6
1.6-1.7
1.7-1.8
1.8-1.9
1.9-2.0
2.0-2.1
2.1-2.2
2.2-2.3
2.3-2.4
0
60
0-0.1
0.1-0.2
0.2-0.3
0.3-0.4
0.4-0.5
0.5-0.6
0.6-0.7
0.7-0.8
0.8-0.9
0.9-1.0
1.0-1.1
1.1-1.2
1.2-1.3
1.3-1.4
1.4-1.5
1.5-1.6
1.6-1.7
1.7-1.8
1.8-1.9
1.9-2.0
2.0-2.1
2.1-2.2
2.2-2.3
2.3-2.4
45
0-0.1
0.1-0.2
0.2-0.3
0.3-0.4
0.4-0.5
0.5-0.6
0.6-0.7
0.7-0.8
0.8-0.9
0.9-1.0
1.0-1.1
1.1-1.2
1.2-1.3
1.3-1.4
1.4-1.5
1.5-1.6
1.6-1.7
1.7-1.8
1.8-1.9
1.9-2.0
2.0-2.1
2.1-2.2
2.2-2.3
2.3-2.4
The frequency percentage of root numbers（%）
Resource 1 Frequency percentage of root numbers in diameter intervals for each order of Pinus
tabuliformis growing in control plots on the Loess Plateau, western China.
60
1st order root
30
15
2nd order root
15
Diamter intervals (mm)
3rd order root
15
Diameter intervals (mm)
4th order root
15
Diameter intervals (mm)
30
Diameter intervals (mm)
5th order root
15
0
Diameter intervals (mm)
Resource 2 Percentage of root number for first to fifth root order of Pinus tabuliformis
included in the five diameter intervals in control plots on the Loess Plateau, China.
Percentage of root
number (%)
100
80
1st order
60
2nd order
40
3rd order
20
4th order
5th order
0
<0.25
0.25-0.37 0.37-0.62 0.62-1.07
Diameter intervals (mm)
>1.07
Resource 3 Percentage of root biomass for first to fifth root order of Pinus tabuliformis
included in the five diameter intervals in control plots on the Loess Plateau, China.
Percentage of root
biomass(%)
100
80
1st order
60
2nd order
3rd order
40
4th order
20
5th order
0
<0.25
0.25-0.37 0.37-0.62 0.62-1.07
Diameter intervals (mm)
>1.07
Resource 4 Diameter divisions (mm) of 75% confidence intervals of root number for first to fifth order
roots of Pinus tabuliformis under different N fertilization treatments on the Loess Plateau, western
China
Root orders
0 (Control)
1st order
2nd order
3rd order
4th order
5th order
[0.13, 0.26]
[0.23, 0.36]
[0.37, 0.50]
[0.71, 1.05]
[1.08, 1.44]
-2
-1
[0.13, 0.26]
[0.23, 0.37]
[0.37, 0.48]
[0.62, 1.01]
[1.07, 1.45]
-2
-1
[0.14, 0.27]
[0.24, 0.37]
[0.39, 0.49]
[0.65, 0.99]
[1.05, 1.43]
-2
-1
3 g N.m .yr
6 g N.m .yr
9 g N.m .yr
[0.14, 0.27]
[0.26, 0.38]
[0.39, 0.59]
[0.65, 1.15]
[1.25, 1.42]
-2
-1
[0.14, 0.29]
[0.27, 0.38]
[0.40, 0.60]
[0.66, 1.16]
[1.26, 1.43]
-2
-1
[0.14, 0.26]
[0.26, 0.40]
[0.41, 0.54]
[0.62, 1.15]
[1.21, 1.41]
12 g N.m .yr
15 g N.m .yr
Note：These 75% confidence intervals of root number for each order were calculated using the normal
distribution based on the large sample size of root number for each root order. In cases where the
distribution does not fit the normal distribution, Student’s t distribution could be used to calculate the
75% confidence intervals.
Resource 5 Critical value of root number between adjacent diameter classes (mm) under different N
fertilization treatments for Pinus tabuliformis on the Loess Plateau, western China
Treatments
0 (Control)
Minimum diameter
1st&2nd
2nd&3rd
3rd&4th
4th&5th
Maximum diameter
0.09
0.25
0.37
0.62
1.07
2.38
-2
-1
0.09
0.25
0.37
0.55
1.04
2.41
-2
-1
0.10
0.26
0.38
0.57
1.02
2.61
-2
-1
3 g N.m .yr
6 g N.m .yr
9 g N.m .yr
0.10
0.27
0.39
0.62
1.20
2.39
-2
-1
0.10
0.28
0.40
0.63
1.21
2.58
-2
-1
0.10
0.28
0.41
0.58
1.18
2.64
0.10
0.27
0.39
0.60
1.12
2.50
12 g N.m .yr
15 g N.m .yr
Mean
Note: The “critical values” of root number for each root order were calculated as follows: Firstly, the
upper critical value of the 75% confidence interval for the lower root order and the lower critical value
of the 75% confidence interval for the higher root order were calculated (see Resource 4); and then the
mean of these two values was calculated to represent the critical value for the two diameter classes. For
example, the critical value of first and second order roots in control plots were the mean of the upper
critical value of the 75% confidence interval for the first root order (0.26 mm) and the lower critical
value of the 75% confidence interval for the second root order (0.23 mm) were calculated as 0.25 mm
(rounded).