On-Field Ohio! Evaluate/Revise the Ohio P Risk Index using Field Scale Edge-of-Field Monitoring Data OSU: Libby Dayton, Chris Holloman, Shane Whitacre, Sakthi Subburayalu, Greg LaBarge, USDA-ARS: Kevin King
USDA-NRCS, Ohio Revised Conservation Practice Standard Nutrient Management, Code 590 Increased Emphasis on Ohio Phosphorus Risk Index which uses Tri-State Fertility Guidelines 4Rs, Nutrient Stewardship 2 http://www.oardc.ohio-state.edu/ocamm/images/oh_590_standard_2012.pdf
Objectives: Project Objectives The Ohio P Index intended to provide a field-scale estimate of P runoff risk Used to judge performance!! 1. Evaluate/revise Ohio P Index, Ohio P Index scores accurately reflect offsite P transport risk 2. Increased management options (BMPs) integrated into the Ohio P Index for fields with high scores 3. Broad implementation of revised and improved Ohio P Index to protect Ohio surface water quality 3
Counties with Current/Pending Project Sites 2 4 2 6 8 in GLSM 7 in Scioto 14 in WLEB 8 5 2 Most with Surface and Sub-surface sampler 20 Current field sites Special Thanks to our Participating Farmers 4
Surface Runoff Set-Up Sample r Ditch Surface runoff Surface runoff drainage area delineation Identify surface runoff drainage area Install sampler Measure water flow (Q) Collect runoff samples 5
Sub-Surface Runoff Set-Up Identify sub-surface drainage area Install sampler Measure water flow (Q) Collect sub-surface runoff samples 6
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Air Dried Sieved and Stored 10
Field/Participating farmer management information What they do, when and how, Yield Soil Physical Properties related to water infiltration New consideration for P Index Closer look at field water management Laboratory Analyses Data Collection Overview Water Samples RTP, RDP, RTN, RDNH 4 and NO 3, Sediment Soil Samples STP (4 methods/2 depths) ph, OC, texture, Total P 11
Water Sampler Data Per Field_Sampler Plot as Timeline PPT (mm) Q (m 3 /A) Runoff Diss. P (RDP) Load (g or lb P/A) Concen. (mgp/l) 3.0 2.5 2.0 1.5 1.0 0.5 180 160 140 120 100 80 60 40 20 200 150 100 50 100 80 60 40 20 0 1/1/12 20-1 Surface, RDP (mg/l) 5/1/12 9/1/12 1/1/13 Date 5/1/13 20-1 Surface, RDP g/a 20-1 Surface, Q (m3/a) 20-1 Surface, PPT (mm) 9/1/13 12 1/1/14
In-Field Factors P Source Factors P Transport Related to Offsite P Transport 13
Ohio P Index Score = Transport Factors + Source Factors Runoff potential Erosion Connectivity to water Filter Strip yes/no Soil test P (STP) Planned P Application amount & method Fairly fixed field/soil characteristic Farmer Management 4Rs! 14
Which Management Practices Are We Studying? Broad range in Management & Field Characteristics Tillage Long-term / Rotational / Lots Fert./Man. Application Method Surface broadcast/ Surface plus incorporation / Band/Inject / No application Drain Control Structures Cover Crop/Residue Cover STP range 9 to 380ppm (Mehlich 3) STP stratification 15
Other Factors We Are Studying? Erosion Potential (RUSLE2) Map Unit Soil Series/Texture Slope steepness and length Hydrologic soil group Farmer Management Runoff Class Slope steepness/hydrologic soil group Connectivity to Water Adjacent to intermittent or perennial stream Concentrated surface flow 16
What Do We Hope to Conclude? Evaluate/Revise: How is P Index Scored?? Is it Correct/Effective?? 1. Evaluate/revise Ohio P Index, Ohio P Index scores accurately reflect offsite P transport risk 2. Increased management options (BMPs) integrated into the Ohio P Index for fields with high scores 3. Broad implementation of revised and improved Ohio P Index to protect Ohio surface water quality 17
Objective1. Evaluate/Revise Ohio P Index Score Accurately Reflects P Runoff Risk Parameter Erosion Potential Connectivity to water 0-16 Runoff Class 0-15 Score Range Ton/acre/yr Soil Test P (bray, ppm) STP X 0.07 Fert/Man. App. Amount P 2 O 5 X 0.05 Fert/Man. App. Method 0-6 < 15 = Lo, 15 30 = Med, 31 45 = Hi, > 45 = Very Hi 18
Objective 2. Increased BMP Options Rank or Rescore BMPs based on Efficacy Fert. App methods Erosion controls Additional BMPs P source coefficient Drain control structures P sorbents Cover crops / Residue cover 19
P Source Coefficient BMP Through OEPA Grant Establish Beneficial Use Guidelines for Drinking Water Treatment Residuals (WTR) Evaluate WTR as P Sorbent (Binder) Allow credit for reduced P solubility for manure/biosolids Develop Method for use Co-blend with liquid swine manure 20
Objective 3. Broad implementation of revised/improved Ohio P Index Education/Promotion in conjunction with OSU Extension, CCAs, DCs (you-all) Simple to Use Farmer can calculate their own P runoff risk Integrated with Tri-State Fertility Guidelines 21
2013 Ohio P Risk Index Scores Presumed P Runoff Risk 50 40 30 20 10 0 Ohio P Risk Index Scores >45 = Very High Assuming drainage ditches are: not streams are streams 30-45=High 15-30 =Med < 15 =Low 4 5 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 32 33 Fields 22
400 350 300 250 200 150 100 50 Avg. Mehlich 3 P (mg/kg) 0-2" depth 0-8"depth 0-2 0-8 min 9.52 8.85 max 385 380 avg 88.1 70.3 42X diff Low to High 0 4 5 6 8 9 101213141516171819202122232425262728293233 Field # 23
Runoff Dissolved P Concentration & Load Strongly Related to STP RDP (mg/l) RDP (lb/a) 2.0 1.5 1.0 0.5 0.0 5 4 3 2 1 0 RDP (mg/l) Concentration r 2 = 0.83 RDP (Lb/A) Load r 2 = 0.90 0 50 100 150 200 250 300 350 400 Mehlich 3 P (mg/kg) 24
Toledo Drinking Water Plant Shut Down Response Media Response Few things Farmers can do NOW!!! Avoid: Overloading soils No P where Bray >40 or M3 >58ppm Winter application of P Frozen or snow covered ground Surface application of P Coordinate tillage to P app. to incorporate Band/inject Minimize Erosion > 30% residue/cover crop 25
Conclusions Ohio Agriculture is being TARGETED Need to REDUCE P load to Ohio surface waters Ohio farmers are actively engaged in being part of the solution A revised Ohio P Risk Index can play an important role in P management Once revised, the P Risk Index will only be effective if it is routinely utilized 26
THANK YOU! 27