Fig. 2. Nitrate nitrogen concentrations in the soil profile under free drainage (FD) and subirrigation (SI) practices in (a) spring 1997, (b) fall 1997, (c) spring 1998, and (d) fall 1998. Vertical bars represent standard error of the mean (n = 9).
Fig. 2. Nitrate nitrogen concentrations in the soil profile under free drainage (FD) and subirrigation (SI) practices in (a) spring 1997, (b) fall 1997, (c) spring 1998, and (d) fall 1998. Vertical bars represent standard error of the mean (n = 9).