Sources of Nitrate in Ground Water Aquifers of the Semiarid Region of Tanzania
Table 2
Identified nitrate sources on shallow wells using the nitrate-chloride ratio during the wet and dry seasons.
Wet season
Dry season
ID
Depth
[NO3−]
[Cl−]
[NO3−]
[Cl−]
[NO3−/Cl−]
Rem.
[NO3−]
[Cl−]
[NO3−]
[Cl−]
[NO3−/Cl−]
Rem.
SW 3
3
37.30
48.50
0.60
1.37
0.44
MN/SE
25.52
60.20
0.41
1.70
0.24
MN/SE
SW 5
20
22.40
155.40
0.36
4.38
0.08
MN/SE
1.76
56.31
0.03
1.59
0.02
MN/SE
SW 8
23
14.10
118.00
0.23
3.32
0.07
MN/SE
47.52
44.66
0.77
1.26
0.61
MN/SE
SW 11
37
125.24
60.63
3.45
2.02
1.71
FT
41.36
122.34
0.67
3.45
0.19
MN/SE
SW 13
6
275.28
71.72
8.97
4.44
2.02
FT
79.20
120.40
1.28
3.39
0.38
MN/SE
SW 14
20
74.50
19.40
1.20
0.55
2.20
MN/SE
54.12
93.21
0.87
2.63
0.33
MN/SE
SW 19
8
330.00
212.00
5.32
5.97
0.89
MN/SE
91.08
155.36
1.47
4.38
0.34
MN/SE
SW 20
9
269.50
237.00
4.35
6.68
0.65
MN/SE
77.00
114.57
1.24
3.23
0.38
MN/SE
SW 21
4
257.25
176.80
4.15
4.98
0.83
MN/SE
60.72
102.92
0.98
2.90
0.34
MN/SE
SW 22
9
270.50
161.20
4.36
4.54
0.96
MN/SE
98.56
106.81
1.59
3.01
0.53
MN/SE
SW 25
9
595.5
260.30
9.60
7.33
1.31
MN/SE
255.20
258.28
4.12
7.28
0.57
MN/SE
SW 26
24
308.14
137.03
4.97
3.86
1.29
FT
322.40
176.44
5.20
4.97
1.04
FT
SW 27
10
71.00
42.70
1.15
1.20
0.95
MN/SE
70.60
29.90
1.14
0.84
1.35
MN/SE
SW 29
7
102.00
63.00
1.65
1.77
0.93
MN/SE
9.90
9.90
0.16
0.28
0.57
MN/SE
SW 32
10
19.60
65.00
0.32
1.83
0.17
MN/SE
60.20
18.90
0.97
0.53
1.82
MN/SE
SW 33
7
60.14
21.66
0.97
0.61
1.59
FT
48.50
10.90
0.78
0.31
2.55
MN/SE
SW 37
3.7
42.78
18.82
0.69
0.53
1.30
FT
116.75
31.90
1.88
0.90
2.10
MN/SE
SW 40
30
282.10
124.25
4.55
3.50
1.30
FT
54.70
343.8
0.88
9.68
0.09
MN/SE
SW 41
30
85.80
273.90
1.38
7.72
0.18
MN/SE
157.25
144.9
2.54
4.08
0.62
MN/SE
SW 46
7
726.00
202.00
11.71
5.69
2.06
MN/SE
679.77
293.9
10.96
8.28
1.32
MN/SE
SW 47
8
1620.00
301.10
26.13
8.48
3.08
MN/SE
929.6
261.00
14.99
7.35
2.04
MN/SE
SW 49
23
1354.00
893.70
21.84
25.17
0.87
MN/SE
286.35
40.90
4.62
1.15
4.01
MN/SE
SW 34
12
51.75
213.70
0.83
6.02
0.14
MN/SE
268.4
180.60
4.33
5.09
0.85
MN/SE
All concentration values ×10−3 Mol/L and ×10−3 g/L. SW represents the identification number for the shallow well sample. MN/SE: manure/sewage effluents; FT: fertilizers, Rem.: remarks; ×10−3 Mol/L.
