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Evaluation of Pesticide Scenarios for the Registration Procedure
Appendix A Description of Karup and Langvad Scenarios
1.1 Conceptual Model
In both scenarios, the conceptual model includes a 2.5 meter soil column separated into four horizons. The Karup site consists of sandy soil, which is considered rather homogeneous neglecting macropore flow. It is situated by the stream Karup Å, why the lower boundary is defined as a constant potential close to field capacity. This approach mimics the free drainage conditions in a deep unsaturated profile overlying a sandy aquifer. The Langvad site consists of loamy soil with macropores, why macropore flow is considered with the macroporosity decreasing from 2% in the top soil to 1% in the deepest horizon. Since the site is situated by the stream Langvad Å, the lower boundary is defined as having a constant gradient, which was calibrated in order to ensure realistic fluctuations of the groundwater table. This approach mimics the situation with shallow topsoil overlaying an aquifer in 2.5 m depth. Artificial drains are installed 1.3 m b.g.s. (Miljøstyrelsen, 1998).
1.2 Data
1.2.1 Climate
Daily climatic data comprising precipitation, min. and max. temperatures and sunshine hours for the two locations were used (ref. Danish Meteorological Institute). The precipitation data were corrected for wind and wetting losses according to Allerup and Madsen (1979), and it was ensured that the annual rainfall compiled with the area mean values, which were originally used for the water balance calculations in Storm et al. (1990). Potential evaporation was calculated using a modified Makkink approach (Aslyng and Hansen, 1982) with the use of radiation data calculated from sunshine hours using the Ångström formula (Iqbal, 1983). Min. and max. air temperatures were used directly. In Table A1 annual precipitation and potential evaporation for the two locations are shown (Miljøstyrelsen, 1998).
Table A1. Climatic data available for Karup and Langvad.
| Year |
Karup |
|
Langvad |
|
| |
Precipitation
(mm/year) |
Potential Evaporation
(mm/year) |
Precipitation
(mm/year) |
Potential Evaporation
(mm/year) |
| 1968 |
895 |
611 |
- |
- |
| 1969 |
647 |
593 |
- |
- |
| 1970 |
848 |
609 |
- |
- |
| 1971 |
702 |
625 |
- |
- |
| 1972 |
714 |
609 |
- |
- |
| 1973 |
650 |
625 |
- |
- |
| 1974 |
862 |
656 |
795 |
645 |
| 1975 |
694 |
649 |
622 |
677 |
| 1976 |
640 |
632 |
609 |
666 |
| 1977 |
941 |
613 |
606 |
635 |
| 1978 |
811 |
574 |
857 |
612 |
| 1979 |
939 |
566 |
662 |
592 |
| 1980 |
1064 |
577 |
805 |
604 |
| 1981 |
1078 |
583 |
769 |
618 |
| 1982 |
891 |
614 |
598 |
667 |
| 1983 |
1017 |
612 |
626 |
630 |
| 1984 |
855 |
607 |
680 |
619 |
| 1985 |
927 |
600 |
689 |
604 |
| 1986 |
904 |
598 |
620 |
611 |
| 1987 |
1044 |
595 |
692 |
575 |
| 1988 |
992 |
607 |
639 |
623 |
| 1989 |
828 |
645 |
562 |
648 |
| 1990 |
1053 |
627 |
650 |
661 |
| 1991 |
901 |
642 |
697 |
628 |
| 1992 |
941 |
685 |
509 |
669 |
| 1993 |
855 |
615 |
818 |
626 |
| 1994 |
1062 |
627 |
744 |
662 |
| 1995 |
799 |
634 |
533 |
660 |
| 1996 |
590 |
614 |
424 |
644 |
1.2.2 Soil
The soil properties and parameters for the Karup and the Langvad groundwater scenario used as input parameters for MACRO 4.4.2. are presented in Table A2- A5.
Table A2. MACRO soil properties for the Karup groundwater scenario
| Property |
Ap horizon |
B1 horizon |
B2 horizon |
BC horizon |
| Thickness [cm] |
20 |
20 |
30 |
180 |
| Texture |
Loamy sand |
Sand |
Sand |
Sand |
| Bulk density [g/cm³] |
1.51 |
1.55 |
1.55 |
1.53 |
| Organic carbon [%] |
2.2 |
1.7 |
0.3 |
0.2 |
| PH |
-99 |
-99 |
-99 |
-99 |
| Structure |
Weak fine granular |
Structureless |
Structureless |
structureless |
Table A3. MACRO soil parameters for the Karup groundwater scenario.
| Parameters |
Ap horizon |
B1 horizon |
B2 horizon |
BC horizon |
| Thickness [cm] |
20 |
20 |
30 |
180 |
| Saturated conductivity [mm h-1] |
200.00 |
125.00 |
125.00 |
720.00 |
| Boundary conductivity [mm h-1] |
1.000 |
2.000 |
2.000 |
10.000 |
| Boundary tension [cm] |
15 |
15 |
15 |
10 |
| Bulk density [g cm-3] |
1.51 |
1.55 |
1.55 |
1.53 |
| Saturated water content [m³ m-3] |
0.420 |
0.420 |
0.420 |
0.420 |
| Boundary water content [m³ m-3] |
0.340 |
0.320 |
0.320 |
0.320 |
Wilting point
[m³ m-3] |
0.100 |
0.060 |
0.060 |
0.040 |
| Effective aggregate half-width [mm] |
1 |
1 |
1 |
1 |
| Pore-size distribution index (mic.) |
0.200 |
0.290 |
0.290 |
0.720 |
| Pore size distribution index (mac.) |
6.0 |
6.0 |
6.0 |
6.0 |
Table A4. MACRO soil properties for the Langvad groundwater scenario.
| Property |
Ap horizon |
Eb horizon |
Ebg horizon |
BCg horizon |
| Thickness [cm] |
20 |
20 |
30 |
180 |
| Texture |
Sandy loam |
Sandy loam |
Sandy loam |
Sandy loam |
| Bulk density [g/cm³] |
1.5 |
1.65 |
1.7 |
1.76 |
| Organic carbon [%] |
2.1 |
1.4 |
0.5 |
0.3 |
| pH |
-99 |
-99 |
-99 |
-99 |
| Structure |
Moderate medium blocky |
Weak medium blocky |
Weak medium blocky |
Weak coarse prismatic |
Table A5. MACRO soil parameters for the Langvad groundwater scenario.
| Parameters |
Ap horizon |
Eb horizon |
Ebg horizon |
BCg horizon |
| Thickness [cm] |
20 |
20 |
30 |
180 |
| Saturated conductivity [mm h-1] |
90.00 |
360.00 |
360.00 |
26.00 |
| Boundary conductivity [mm h-1] |
0.500 |
0.100 |
0.100 |
0.080 |
Boundary tension
[cm] |
10 |
12 |
12 |
25 |
| Bulk density [g cm-3] |
1.50 |
1.65 |
1.70 |
1.76 |
Saturated water content
[m³ m-3] |
0.450 |
0.360 |
0.360 |
0.340 |
Boundary water content
[m³ m-3] |
0.430 |
0.340 |
0.340 |
0.330 |
Wilting point
[m³ m-3] |
0.140 |
0.120 |
0.120 |
0.150 |
| Effective aggregate half-width [mm] |
20 |
20 |
20 |
20 |
| Pore-size distribution index (mic.) |
0.150 |
0.150 |
0.150 |
0.150 |
| Pore size distribution index (mac.) |
5.0 |
5.0 |
5.0 |
5.0 |
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Version 1.0 August 2007, © Danish Environmental Protection Agency
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