Soil Phosphorus Dynamics of Wheat-Based Cropping Systems in the Semiarid Region of Argentina
Table 2
Soil organic carbon (SOC), organic (Po), inorganic (Pi), total extractable (Pte), total and extractable phosphorus (Pe), Po : (Po + Pi) relationships, and pH of different cropping systems (CS).
Year
CS
SOC
Po
Pi
Po : (Po + Pi)
Pte
Pt
Pe
pH
%
mg kg−1
mg kg−1
0
Ref
1.28
189.0
328.0
0.37
529.0
562.1
30.9
6.7
9
WG
1.13a*
77.7a**
294.7a*
0.20a**
289.6b**
412.2b*
14.3b**
6.8a ns
WW
0.89b**
50.4b**
172.0b**
0.22a**
230.0b**
396.3b*
11.7b**
6.6b ns
WL
1.14a*
82.2a**
290.5a*
0.22a**
417.3a*
456.3a*
33.7a ns
6.6b ns
10
WG
1.08a
133.7a
231.1a
0.37a
396.7a
418.0a
10.2b
6.4ab
WW
0.84b
75.5b
159.0b
0.32b
344.1b
378.2ab
13.1b
6.3b
WL
1.11a
107.3ab
230.5a
0.32b
339.7b
362.1b
21.2a
6.5a
11
WG
1.07a
86.7
217.5b
0.38a
350.2a
440.0a
15.7b
6.3a
WW
0.85b
84.0
176.3c
0.32b
316.8b
407.2a
18.8b
6.3a
WL
1.12a
81.5
245.7a
0.33b
289.7b
328.4b
26.0a
6.1b
12
WG
1.16a
85.4
218.1b
0.28a
343.0a
420.0a
11.6b
6.4a
WW
0.95b
65.7
233.7ab
0.22b
365.2a
411.3a
27.2a
6.1b
WL
1.27a
78.3
250.2a
0.24b
280.1b
321.6b
10.4b
6.2b
, and ns indicate statistical differences , and not significant, respectively, between each treatment sampled in year 9 and reference soil. For SOC, each P form and pH, different letters indicate differences among treatments in each year.