On-Field Ohio! Evaluate/Revise the Ohio P Risk Index using Field Scale Edge-of-Field Monitoring Data

Transcription

1 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

2 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

3 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

4 Counties with Current/Pending Project Sites in GLSM 7 in Scioto 14 in WLEB Most with Surface and Sub-surface sampler 20 Current field sites Special Thanks to our Participating Farmers 4

5 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

6 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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10 Air Dried Sieved and Stored 10

11 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

12 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) /1/ Surface, RDP (mg/l) 5/1/12 9/1/12 1/1/13 Date 5/1/ Surface, RDP g/a 20-1 Surface, Q (m3/a) 20-1 Surface, PPT (mm) 9/1/ /1/14

13 In-Field Factors P Source Factors P Transport Related to Offsite P Transport 13

14 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

15 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

16 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

17 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

18 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, = Med, = Hi, > 45 = Very Hi 18

19 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

20 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

21 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

22 2013 Ohio P Risk Index Scores Presumed P Runoff Risk Ohio P Risk Index Scores >45 = Very High Assuming drainage ditches are: not streams are streams 30-45=High =Med < 15 =Low Fields 22

23 Avg. Mehlich 3 P (mg/kg) 0-2" depth 0-8"depth min max avg X diff Low to High Field # 23

24 Runoff Dissolved P Concentration & Load Strongly Related to STP RDP (mg/l) RDP (lb/a) RDP (mg/l) Concentration r 2 = 0.83 RDP (Lb/A) Load r 2 = Mehlich 3 P (mg/kg) 24

25 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

26 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

27 THANK YOU! 27