Use of Airborne Hyperspectral Imagery to Map Soil Properties in Tilled Agricultural Fields
Table 4
Predicted concentrations of select analytes (C, Silt, Al, Fe) derived from pixels of near infrared hyperspectral imagery for each of the six bare soil fields using either unsmoothed (1-pixel) imagery with 2.5 m resolution, or spatially smoothed (9-pixel) imagery to which a low pass filter had been applied1. See Section 2 for analyte descriptions.
C
Silt
Al
Fe
Field
1-pixel%
9-pixel%
1-pixel%
9-pixel%
1-pixel mg/kg
9-pixel mg/kg
1-pixel mg/kg
9-pixel mg/kg
Temple 1S
min
0.97
1.13
14.6
14.4
34
245
40
56
max
1.86
1.94
80.1
58.7
1017
947
474
394
mean
1.41
1.48
42.1
41.1
633
631
194
192
sd
0.10
0.10
5.9
5.0
98
92
46
44
Temple 1N
min
0.85
0.96
1.0
5.6
−31
147
37
64
max
1.95
2.04
68.9
59.1
1304
897
452
429
mean
1.23
1.25
43.6
42.1
589
555
200
210
sd
0.11
0.11
5.8
4.9
115
112
60
65
Temple 2
min
−0.48
0.81
14.6
8.7
34
−389
40
54
max
2.07
2.92
80.1
75.7
1017
1013
474
529
mean
1.27
1.28
42.1
38.2
633
512
194
226
sd
0.25
0.18
5.9
7.1
98
146
46
63
Temple 3
min
0.39
0.60
0.2
1.2
−137
0
−288
−6
max
2.29
2.48
80.8
74.9
1173
1031
465
474
mean
1.27
1.27
52.3
51.7
632
639
173
170
sd
0.17
0.16
7.9
7.5
154
145
71
63
Mason
min
0.41
0.44
−7.6
−7.5
−198
290
0
0
max
2.27
1.94
64.9
48.5
1231
1180
391
391
mean
0.81
0.81
27.7
28.7
755
776
111
108
sd
0.11
0.10
6.4
7.1
96
100
32
27
Schrader
min
0.91
0.98
12.3
13.4
255
296
58
66
max
2.08
2.05
61.6
56.9
996
971
346
315
mean
1.45
1.48
38.6
38.3
669
681
177
172
sd
0.13
0.15
6.0
5.8
87
81
35
34
Overall
min
0.97
1.13
14.6
14.4
255
296
58
66
max
1.86
1.94
61.6
48.5
996
897
346
315
mean
1.20
1.22
41.3
40.5
660
648
168
171
1See Table 3 for the accuracy () associated with each analyte prediction model.