Analysis of the Spatial Variation of Soil Salinity and Its Causal Factors in China’s Minqin Oasis
Table 2
Descriptive statistics for the soil parameters, by land use and cover class (LUCC).
LUCC (sample size)
Parameters
Range
Mean
SD
CV
LUCC description
Cropland (21)
(dS/m)
0.11–9.66
1.35
2.39
1.77
This class includes land covered with crops (e.g., fennel, cotton, alfalfa, wheat, maize, sunflower, and goji berry), newly cultivated land, and fallow land.
7.82–8.76
8.32
0.24
0.03
SMC (%)
0.86–13.81
7.15
2.77
0.39
GW salinity (g/L)
2.11–27.39
14.59
6.09
0.42
GW table depth (m)
5.32–32.33
18.61
7.99
0.43
Shrubland (9)
(dS/m)
0.12–14.89
3.23
4.45
1.38
Land with woody vegetation, with a total shrub cover that exceeds 10% of the surface. Some of this land resulted from a local policy of replacing cropland with shrubs to combat desertification.
8.05–8.99
8.38
0.31
0.04
SMC (%)
1.47–6.03
3.19
1.61
0.50
GW salinity (g/L)
9.68–27.91
15.53
6.38
0.41
GW table depth (m)
7.17–29.95
18.47
8.34
0.45
Abandoned land (5)
(dS/m)
0.21–1.41
0.99
0.41
0.42
Land has been abandoned for 5 to 20 years, with vegetation cover <5%.
7.96–8.83
8.35
0.3
0.04
SMC (%)
1.54–4.55
2.66
1.07
0.40
GW salinity (g/L)
10.06–18.44
13.22
3.45
0.26
GW table depth (m)
10.89–28.78
20.05
6.66
0.33
Sparse grassland (46)
(dS/m)
0.15–21.44
6.18
5.01
0.81
Land has been abandoned for more than 20 years. Dominated by grasses and salt-tolerant grasses, with vegetation cover of 5% to 20%.
7.89–8.75
8.34
0.22
0.03
SMC (%)
0.93–10.18
4.08
2.14
0.52
GW salinity (g/L)
6.51–23.27
14.12
4.19
0.30
GW table depth (m)
7.18–36.05
22.70
6.33
0.28
Saline wasteland (13)
(dS/m)
8.28–23.10
14.6
5.12
0.35
Land with a salt crust at the soil surface. Dominated by natural salt-tolerant grasses, with vegetation cover >20%. Naturally salt-affected areas are distributed at the margins of the oasis.
7.88–8.58
8.36
0.22
0.03
SMC (%)
3.91–14.96
8.87
3.09
0.35
GW salinity (g/L)
7.55–19.97
11.20
3.39
0.30
GW table depth (m)
6.76–29.42
15.80
8.29
0.52
SMC represents the soil moisture content as a percentage of the dry soil weight. GW represents the groundwater.
