Too much nitrogen (N) in surface water is harmful to aquatic life. Subsurface drains, some along with surface inlets, are commonly used for drainage of agricultural land in humid regions and contribute unknown N amounts to surface water. Quantification of relative amounts moving through...

Controlled tile drainage (CTD) is a management practice designed to retain water and nutrients in the field for crop use. CTD has shown promise for improving water quality and augmenting crop yields but findings are often restricted to field and plot scales. Remote sensing is one of the...