Table D.4.
Ratio between new and former mean annual irrigation volumes for the three irrigated R scenarios. Field crops: new option 5 (over canopy, without surface run‐off; tall crops: new option 6 (under canopy, without surface run‐off). Parameter settings: PCDEPL = 0.4. FLEACH = 0; RATEAP = 0.125
| Scenario | Mean | SD | Sample sizea |
|---|---|---|---|
| R1‐Weiherbach | 1.26b | 0.34 | 8 |
| R3‐Bologna | 0.98 | 0.18 | 12 |
| R4‐Roujan | 1.16 | 0.64 | 11 |
| R‐4 Roujan without soybean | 0.98 | 0.14 | 10 |
a
The two cropping seasons of leafy vegetables were counted as one crop, because in FOCUS (2001) irrigation occurs also between the two cropping seasons.
b
If the soil profile depth of R1 were increased, irrigation volumes for Weiherbach would decrease for the crops rooting deeper than 1 m that are irrigated in R1 (maize and sugar beet).