Effect of Land Application of Phosphorus-Saturated Gypsum on Soil Phosphorus in a Laboratory Incubation
Table 3
Effect of soil type and time on soil water-extractable phosphorus and Mehlich 3 phosphorus concentrations averaged across phosphorus saturation level and gypsum rate†.
Soil type
Days after Amendment
1
7
28
63
91
119
183
(mg kg−1)
Soil water extractable phosphorus concentration
Sandy loam
17.8 a
14.3 ab
14.1 ab
15.0 ab
9.4 bc
9.5 bc
9.1 bc
Silt loam
12.8 ab
8.0 bc
6.5 bc
5.6 bc
5.3 c
4.8 c
4.6 c
Unamended sandy loam
6.8
6.8
5.9
5.2
5.3
5.3
5.3
Unamended silt loam
5.2
5.3
5.7
4.8
4.1
4.1
4.0
Soil Mehlich 3 phosphorus concentration
Sandy loam
73.2 d
57.6 d
98.3 bc
111.8 ab
127.1 a
87.2 c
83.5 c
Silt loam
64.2 d
62.3 d
68.9 d
107.2 b
91.1 c
58.5 d
50.0 d
Unamended sandy loam
49.3
54.9
57.0
82.1
99.7
62.9
60.7
Unamended silt loam
41.0
35.6
42.0
77.8
69.8
42.2
37.8
followed by different letters were determined to be significantly different at . Means for the unamended soils were not compared statistically to the amended soils.
