E-mail: pearl@rivm.nl

1. EURO PEARL Modelling the Leaching of pesticides at the Pan-European level Aaldrik Tiktak, Danielle de Nie, Juan Piñeros Garcet,Marnik Vanclooster, Arwyn Jones E-mail: pearl@rivm.nl

2. The EuroPEARL model • Work package 6 of APECOP project • Model parameterisation • Results: • water balances • substance balances • leaching concentration • comparison with FOCUS • Conclusions and shortcomings E-mail: lbg-pearl@rivm.nl

3. Outline: Work package 6 of APECOP project Model parameterisation Results Conclusions and shortcomings E-mail: lbg-pearl@rivm.nl

4. Work package 6 of APECOP • Aim of this work package is to evaluate the validity of the FOCUS scenarios. • Partners in this work package are: • RIVM (Aaldrik Tiktak & Danielle de Nie) • Université de Louvain-la-Neuve (Marnik Vanclooster & Juan Piñeros • JRC (Arwyn Jones)

5. Scenario validation • The exact 90th percentile cannot be determined precisely without extensive simulations of the various combinations present in a region; • Models at the European scale can provide an answer to this question: • maps of the leaching concentration for all agricultural soils in Europe • frequency distributions

6. Outline: Work package 6 of APECOP project Model parameterisation Results Conclusions and shortcomings E-mail: lbg-pearl@rivm.nl

7. Parameterisation of EuroPEARL • Step 1: Derivation of the unique combinations, based on climate and soil mapping units; • Step 2a: Parameterisation of the soil profiles (linkage between soil map and Soil Profile Analytical Database of Europe, SPADE); • Step 2b: Parameterisation of weather conditions for each individual plot; • Step 3: Translation into model parameters, using pedotransfer functions etc.

8. Step 1: Derivation of Unique Combinations (UC) • Country • Based on the SMU soil map • Soil Map (FAO) • Created by JRC • 1:1.000.000 • ‘STU’ info • FOCUS areas • LU mask • Precipitation and temperature maps

9. Step 1: Unique Combinations • 1410 plots. • Each UC contains info about: • SMU • Country • FOCUS Area

10. Step 2a: Combine SPADE & SMU’s to PEARL profiles Soil Map of Europe SMU SMU number; Country; STU 1 number; STU 1 coverage; …... STU n number; STU n coverage; Dominant STU number1 1 Soil Profile Analytical Database STU number1,2 Country2; FAO Soil Name2; Texture class2; Other parameters. 2 Soil profile number (STU number)2; Country2; FAO Soil Name2; Texture class2; Horizon numbers3; Other parameters 3 1: Establish dominant STU 2: STU -> profile # 3: Profile # -> Horizon # Soil Horizon number3 Horizon depth; Profile number; Organic matter; Texture; pH.

11. Basic soil data: Peat soils Extreme low Lightly textured Calcareous soils

12. Step 2b: Combine daily weather & climate maps • 9 FOCUS area’s • Meteo district • Daily time series • Potential evapotranspiration • UC • Temperature • Precipitation Scaling Daily weather datafor each UC

13. Area assigned a soil profile: • Sweden, Finland and Austria not in SPADE • 1062 unique combinations linked to SPADE • 75 % of the area parameterised

14. Substance Substance properties, such as the half-live and the partitioning coefficient Application type Application dosage Step 3: specific model parameters Plot ID Rainfall Temperature ETref Irrigation switch Run Substance ID Plot ID Start date End date Soil layer Soil physical unit ID Layer thickness Texture Organic matter pH Soil physics Parameters of the Mualem-van Genuchten functions Dispersion length Soil profile Soil layer ID Plot Plot ID FOCUS Area ID Land-use type ID Soil profile ID Groundwater depth group ID Seepage flux and amplitude Drainage characteristics FOCUS Area Emergence date Harvest date Development stage ID Critical pressure headsfor drought stress andirrigation Management ID Management Application date Development stage LAI Crop factor Rooting depth Spatially distributed variables

15. Irrigation scenario’s in EuroPEARL: • No irrigation for winter wheat; • Maize is irrigated if: • The pressure head drops below a critical value (-500cm or pF 2.7) • AND • Over 2.5% of the area is equipped for irrigation • The presence of an irrigation system is derived from inventories by Siebert and Döll, University of Kassel.

16. Inventories by Siebert & Döll:

17. Additional remarks: • No linkage with a regional groundwater model; no simulation of interflow (lateral drainage); • Groundwater fixed at 2 m depth. • Calculations carried out for one crop in a time: • winter wheat with no irrigation; • maize with irrigation; • Crop properties including emergence and harvest date linked to FOCUS area; • Pre-emergence applications simulated - so application date coupled with FOCUS area.

18. Results: Water balances; Substance fluxes; 80th percentile of the leaching concentration; Comparison with FOCUS.

19. Water balance simulated with EuroPEARL High rainfall rates High irrigation rates Enhanced by irrigation Corresponding patterns

20. Results: • Water balances; • Substance fluxes; • 80th percentile of the leaching concentration; • Comparison with FOCUS.

21. Maps of the substance balances: High MA < WC

22. Results: • Water balances; • Substance fluxes; • 80th percentile of the leaching concentration; • Comparison with FOCUS.

23. 80th percentile of leaching concentration Winter wheat > maize High leaching risk Southern countries are not always less vulnerable!!!!

24. Variance due to weather conditions (substance A) • (80th-20th)/50th percentile due to weather conditions;

25. Results: • Water balances; • Substance fluxes; • 80th percentile of the leaching concentration; • Comparison with FOCUS.

26. Properties of FA compared with FOCUS • FOCUS close to 20th percentile of organic matter and clay • OM of FS Port >> FA Port!

27. 80th percentile per FOCUS area (wheat scenario) • Differences for the warm scenario’s PO, PI and SE; • OK for temperate scenario’s

28. 80th percentile per FOCUS area (maize scenario) • Larger differences due to irrigation effect • Also here: largest differences for warm scenario’s

29. Outline: Reminder: Work package 6 of APECOP project Model parameterisation Results Conclusions and shortcomings E-mail: lbg-pearl@rivm.nl

30. Leaching concentration: • Leaching increases with increasing precipitation and decreases with increasing organic matter content; • Hotspots occur also in Southern Europe; • Difference between maize (spring application) and wheat (autumn application) • Absolute level higher for wheat; • Differences for warm scenarios are obvious (PO underestimated by FOCUS, PI overestimated).

31. Shortcomings of current procedure: • Soil database (SPADE): • contains estimated profiles; • does not give full coverage; • differences across Europe still present; • only dominant STU’s can be linked. • Groundwater: • fixed at 2 m below soil surface; • no run-off & interflow calculations. • Weather data: • simple scaling procedure. • Land use mask: • only distinction arable/non-arable land.

32. Future improvements: • From SPADE to SPADE-2: • full coverage; • provide more information on variability. • Groundwater: • make use of aquifer inventories by ECPA. • include simple run-off calculations or accept ‘worst-case’ • Weather data: • direct extraction from MARS database. • Land use mask: • no improvement foreseen.