Look to the FuturePlanted area: Corn, wheat, and soybeansMillion acres100 90 Corn 80 Soybeans 70 60 Wheat 50 40 1980 1985 1990 1995 2000 2005 2010 2015 Source: USDA Agricultural Projections to Projections to USDA Agricultural 2016, February 2007. 2016 Economic Research Service, USDA. D. R. Keeney
Corn/Soybean and PerennialNitrate-N Concentrations in Tile Drain 25 Tile drainage system 20 U of MN - Lamberton Gyles Randall, 2003 15 mg/L Midpoint 10 of range 5 0 Corn/Bean Perennials D. R. Keeney
Iowa Daily Erosion Project Estimates daily soil erosion, runoff and soil moisture for the state of Iowa Daily estimations since 2002 Published in Jan/Feb 2006 Journal of the Soil and Water Conservation Society Served on the web at http://wepp.mesonet.agron.iastate.edu Parameterizes WEPP erosion model with radar rainfall, climate stations, and NRI
Simulated crops Eight scenarios based on ISU research Residue Cover Rotation Tillage Abbreviation Removal Crop NRI NRI No No NRI Corn/Soy Min-till No No CS-MT Cont. Corn Min-till Yes No CC-MTRR Corn/Soy No-till No No CS-NT Cont. Corn No-till No No CC-NT Cont. Corn No-till Yes No CC-NTRR Cont. Corn No-till Yes Yes CC-NTRRCC Switchgrass No-till Yes No Sw-NTRR
NEXRAD – Aug 22, 2007 Statewide mean precipitation: 1.56 in.
Thoughts to Ponder Corn grain ethanol N applications likely unchanged P applications likely unchanged Water quality impacts likely unchanged Cover crop management good for system
Thoughts to Ponder (II) Cellulosic - conversion of corn stalks Likely greater water quality challenges than current ag systems Opportunities with cover crops to improve WQ Sediment/Phosphorus issues increase Cellulosic – conversion of perennials Favorable WQ opportunities • Surface • Subsurface