Sustainable Reuse of Dredged Soil as a Substrate Material by Improvement with Polyacrylamide, Straw, and Superabsorbent Polymer
Table 3
Range analysis of variance for soil organic matter; extractable N, P, and K; bulk density; total porosity; saturated water capacity; and germination rate.
Items
Coefficient
k1
k2
k3
k4
k5
R
Order of the factor
Optimal combination (g/kg）
Organic C
PAM
5.85
6.15
5.55
6.01
5.7
0.61
Straw > SAP > PAM
A2 (1.0 g/kg)
Straw
5.46
5.27
5.53
5.68
7.31
2.05
B5 (35 g/kg)
SAP
5.13
5.79
5.96
6.03
6.34
1.22
C5 (12 g/kg)
Extractable N
PAM
85.31
73.53
84.94
93.08
94.98
21.45
Straw > PAM > SAP
A5 (2.5 g/kg)
Straw
76.89
81.76
82.03
91.84
99.32
22.43
B5 (35 g/kg)
SAP
79.73
94.84
86.56
84.5
86.2
15.12
C2 (3 g/kg)
Extractable P
PAM
148.37
119.94
116.32
111.97
134.17
36.4
Straw > SAP > PAM
A1 (0.5 g/kg)
Straw
133.19
140.8
164.03
105.11
87.64
76.38
B3 (25 g/kg)
SAP
144.77
129.74
107.68
118.18
130.4
37.08
C1 (0 g/kg)
Extractable K
PAM
591
639.33
496.53
438.91
396.09
243.24
Straw > PAM > SAP
A2 (1.0 g/kg)
Straw
660.84
435.48
623.05
527.46
315.04
345.8
B1 (15 g/kg)
SAP
426.78
551.52
462.29
561.59
559.69
134.81
C5 (12 g/kg)
Bulk density
PAM
1.032
1.032
1.048
0.996
0.994
0.054
SAP > PAM > straw
A5 (2.5 g/kg)
Straw
1.014
1.03
1.044
1.018
0.996
0.048
B5 (35 g/kg)
SAP
1.174
1.072
1.032
0.97
0.854
0.32
C5 (12 g/kg)
Total porosity
PAM
55.83
57.336
57.626
59.482
61.444
5.614
SAP > PAM > straw
A5 (2.5 g/kg)
Straw
58.46
59.432
57.918
58.712
57.196
2.236
B2 (20 g/kg)
SAP
53.366
54.58
57.572
61.472
64.728
11.362
C5 (12 g/kg)
Saturated water capacity
PAM
0.566
0.582
0.588
0.626
0.646
0.08
SAP > PAM > straw
A5 (2.5 g/kg)
Straw
0.612
0.612
0.588
0.602
0.594
0.024
B1 (20 g/kg)
SAP
0.484
0.526
0.58
0.66
0.758
0.274
C5 (12 g/kg)
Germination rate
PAM
12.8
10.8
8
9.6
9.6
4.8
PAM > SAP > straw
A1 (0.5 g/kg)
Straw
8.2
9.8
11
10.6
11.2
3
B5 (35 g/kg)
SAP
8
11.6
11.6
11.2
8.4
3.6
C2 (3 g/kg)
R is the range; ki is the average value of the index sum corresponding to the level factor.
