Spatiotemporal Variation Characteristics of Water Pollution and the Cause of Pollution Formation in a Heavily Polluted River in the Upper Hai River
Table 2
Statistics of the measured parameters and the national standards for surface water quality.
Summary statistics of measured parameters
Environmental quality standard1
Parameters
Unit
Minimum
Maximum
Mean
SD
CV%
I
II
III
IV
V
T
°C
1.50
33.50
18.47
8.31
45.01
—
—
—
—
—
pH
—
6.22
9.43
7.77
0.48
6.13
6∼9
6∼9
6∼9
6∼9
6∼9
DO
mg/L
0.10
19.80
5.54
3.52
63.47
7.5
6
5
3
2
CODCr
mg/L
4.20
230.00
61.45
34.33
55.86
15
15
20
30
40
BOD5
mg/L
0.25
39.70
7.31
5.89
80.59
3
3
4
6
10
NH3–N
mg/L
0.01
37.10
5.20
5.24
100.81
0.15
0.5
1
1.5
2
TP
mg/L
0.01
12.41
0.43
0.65
153.86
0.02
0.1
0.2
0.3
0.4
F−
mg/L
0.17
7.51
1.06
0.57
53.67
1
1
1
1.5
1.5
CN
μg/L
0.50
20.00
2.73
2.15
78.64
5
50
200
200
200
VP
μg/L
0.15
267.50
8.41
26.70
317.45
2
2
5
10
100
Cu
μg/L
0.50
399.00
8.30
28.01
337.36
10
1000
1000
1000
1000
Zn
μg/L
25.00
1650.00
78.20
167.32
213.96
50
1000
1000
2000
2000
Pb
μg/L
1.25
490.00
10.01
29.02
289.85
10
10
50
50
100
Cd
μg/L
0.25
39.00
1.33
2.89
216.61
1
5
5
5
10
Cr6+
μg/L
2.00
44.00
2.14
2.22
103.97
10
50
50
50
100
1Environmental Quality Standard: the environmental quality standards for surface water in China (GB 3838–2002); SD: standard deviation; CV: coefficient of variation.
