Pictured Above: PHOSPHOROUS FLOWS. USDA research ag engineer Kevin King says that between surface and tile runoff, tile is the major contributor to annual dissolved reactive phosphorus loading in the Maumee watershed. Only 6% of rainfall events were greater than 2 inches, but that alone accounted for 45% of nutrient discharge from tile lines.
Photo Courtesy of Jed Stinner, USDA - ARS
For no-tillers with poorly drained soils, tile drainage has become a necessity to prevent oversaturated soils that hurt crops and the bottom line.
But for the Great Lakes and Gulf of Mexico, some experts believe more tile equates to more nutrient runoff from agriculture fields, contributing to toxic algae blooms and dead zones.
In northwest and central Ohio, USDA-ARS researchers installed edge-of-field monitoring systems on 20 sites to study nutrient loss via surface runoff and tile drainage.
At the 2016 National No-Tillage Conference in Indianapolis, USDA research agriculture engineer Kevin King shared what researchers learned through 5 years of research, and some changes in field management no-tillers may need to make to keep more fertilizer in their fields.
Whether a no-tiller subscribes to climate change or not, King says there’s no denying there have been shifts in the timing and intensity of rainfall over the last couple decades, directly impacting fertilizer application and nutrient runoff.
King says a lot of fertilizer application used to take place in the fall. But in reviewing data from 2005-14, researchers note an increase in the amount of precipitation received in…