Agriculture Reference
In-Depth Information
sedimentation method [22], pH was determined in 1:1 (wt/vol) diluted wa-
ter suspensions [23], electrical conductivity was determined with a CO150
conductivity meter according to the manufacturer's instructions (Hach
Company, Loveland, CO, USA). Total organic matter was measured using
the reduction of potassium dichromate method of Walkley and Black, as
described by Nelson and Sommers [24]. Furthermore, ammonium (NH
4
+
),
nitrite and nitrate [25], calcium (Ca
2+
) [26], magnesium (Mg
2+
), phosphate,
sulfate [27] were quantified. All soil parameters measured are given in
Table 1.
TABLE 1:
Physico-chemical characteristics (average ± standard deviation) for soils from
different sites and land use.
Site 1
Site 2
Alfalfa
scrubland
Alfalfa
scrubland
pH value
8.65 ± 0.12
8.7 ± 0.27
8.62 ± 0.06
8.1 ± 0.64
Electric conductiv-
ity [mS cm
-1
]
0.86 ± 0.14
0.59 ± 0.18
1.45 ± 0.33
1.3 ± 1.71
CA
2+
[mg kg
-1
]
8.67 ± 2.16
9.89 ± 3.36
10.83 ± 4.56
13.2 ± 14.17
Mg
2+
[mg kg
-1
]
5.42 ± 1.38
5 ± 0.98
13.34 ± 5.32
6.63 ± 6.46
K
+
[mg kg
-1
]
4.59 ± 1.62
4.8 ± 1.99
5.09 ± 2.7
4.01 ± 2.14
Na
+
[mg kg
-1
]* +
33.22 ± 6.34
13.86 ± 9.37
44.56 ± 8.2
26.4 ± 32.55
Phosphate
[mg kg
-1
]*** -
5.2 ± 1.33
41.62 ± 19.15
7.21 ± 3.32
30.31 ± 17.97
NH
4
+
-N [mg kg
-1
]
10.14 ± 4.1
7.44 ± 1.53
10.48 ± 2.17
10.14 ± 3.3
Total nitrogen [mg
kg
-1
]
482.39 ± 179.03
450.48 ± 76.27
358.29 ± 130.19
308.65 ± 170.74
Cl
-
[mg kg
-1
]
37.6 ± 5.28
11.57 ± 7.57
60.23 ± 15.41
65.64 ± 110.05
NO
2
-
N [mg kg
-1
]
0.05 ± 0.03
0.03 ± 0.03
0.09 ± 0.16
0.03 ± 0.04
NO
3
-
N [mg kg
-1
]*+
2.62 ± 0.72
0.66 ± 0.5
1.18 ± 1.92
0.23 ± 0.22
Sulphate
[mg kg
-1
]***+
8.35 ± 1.63
4.79 ± 1.33
29.28 ± 6.24
2.97 ± 0.92
Organic matter
[% volumetric]*-
0.45 ± 0.06
0.79 ± 0.18
0.44 ± 0.11
0.58 ± 0.32
Two-way ANOVA was used to test for significant differences in soil parameters between
land use. The significant level between land use was indicated as *p < 0.05; ***p < 0.001;
+: significantly increased in agricultural soils;
-: significantly decreased in agricultural soils.
