TABLE 1. Nitrate (NO3-N) and nitrogen isotope ( 15N) data from selected wells. Samples from May 6, 2000, are prior to fertilizer application, while samples of May 31, 2000, were taken after fertilizer application. Wells 5, 16, and 22 are in fields that acquired high applications of nitrogen.
|
| Well ID |
Depth (m) |
NO3-N (mg/L) |
15N (o/oo) |
NO3-N (mg/L) |
15N (o/oo) |
| May 6, 2000 |
May 31, 2000 |
| 1sh |
~5.00 |
6.81 |
+10.4 |
5.97 |
+9.18 |
| 4sh |
~5.00 |
3.69 |
+5.54 |
3.83 |
+6.88 |
| 4d |
14.5 |
NS |
- |
NS |
- |
| 5s |
6.11 |
14.5 |
+0.42 |
15.3 |
-0.33 |
| 6s |
4.2 |
13.0 |
-0.67 |
12.5 |
-1.12 |
| 7s |
4.61 |
20.9 |
-1.38 |
19.8 |
-1.54 |
| 7d |
18.2 |
NS |
- |
NS |
- |
| 14s |
5.47 |
15.5 |
+5.98 |
14.1 |
+7.64 |
| 16s |
4.18 |
14.7 |
+6.11 |
16.0 |
+7.05 |
| 16d |
12.1 |
NS |
- |
NS |
- |
| 21d |
10.3 |
NS |
- |
NS |
- |
| 22s |
3.47 |
15.8 |
+0.69 |
17.1 |
+1.21 |
| 22d |
14.9 |
0.1 |
NM |
0.1 |
NM |
|