1. INVESTIGATING CONSERVATION AGRICULTURE SYSTEMS IN ZAMBIA AND ZIMBABWE TO MITIGATE FUTURE EFFECTS OF CLIMATE CHANGE By Christian Thierfelder and Patrick C. Wall

2. Table of content  Introduction  Brief description of trial sites  Effects of CA on infiltration and soil moisture  Yield responses to soil moisture  Conclusions

3. Introduction: Most models suggest that the southern African region will be affected by climate change IPCC, AR4, 2007

4. Effect of climate change on crops in southern Africa  The big losers in southern Africa in terms of production will be maize and wheat (Lobell et al., 2008. Science)

5. Farmer need to adapt to the new situation!  Change in management (date of planting)  Change in variety e.g. to shorter (or longer?) season varieties  Change in fertiliser use (targeting and concentrating fertilizers)  Change in crops - e.g. to more drought resistance species  Change towards water-efficient cropping systems

6. Water efficient cropping systems: Retain more water on-site through:  Higher infiltration  Less water run-off  Reduced evaporation  Higher water storage in the soil  Higher biological activity (earthworms create soil pores) The more water can be retained and stored on-site the more there is available for crop production! Effects of CA on Earthworm counts, Monze, FTC, Zambia 2007

7. What is Conservation Agriculture?  CA comprises the following principles: –Minimal soil movement –Surface crop residue retention –Crop rotations and green manure cover crops

8. Locations Henderson Research Station (HRS), Mashonaland Central Province, Zimbabwe 17.57°S, 30.99°E, 1136 m.a.s.l Monze, Farmers Training Center (MFTC), Zambia 16.24°S, 27.44°E, 1103 m.a.s.l

9. Brief description of treatments  Conventional ploughing, maize, no residues  CA: direct seeding, maize, residue retention  CA: direct seeded rotation, maize after cotton, residues retention   Conventional ploughing, maize, no residues   CA: direct seeding, maize, residue retention   CA: rip-line seeding, maize, residue retention Henderson Research Station, Zimbabwe (HRS) Monze, Farmer Training Centre, Zambia (MFTC)

10. Infiltration curves measured by mini-rainfall simulator in January 2008 (left) and 2009 (right) in two conservation agriculture and one conventional treatment, Henderson Research Station, Zimbabwe January 2008 January 2009

11. Infiltration curves measured by mini-rainfall simulator in January 2008 (left) and 2009 (right) in two conservation agriculture and one conventional treatment, Monze, Farmer Training Centre, Zambia January 2008 January 2009

12. Crops are at tasseling Available soil moisture in the first 60cm at the Monze Farmer Training Centre, Zambia, 2005/2006 Crops are at tasseling

13. Soil moisture measurements, Monze, FTC, 2008/2009

14. Initial crop development Available soil moisture in the first 60cm at the, Monze Farmer Training Centre, Zambia, 2008/2009 Initial crop development

15. Maize grain yield in four consecutive years at Monze Farmer training Centre, 2005-2009

16. Maize grain yield in five consecutive years at Henderson Research Station, Zimbabwe, 2004-2009

17. Conclusions:  CA has the potential to improve the soil water balance of major cropping systems in southern Africa and mitigate seasonal dry spells  At HRS, Zimbabwe and MFTC, Zambia a generally higher infiltration and soil moisture content was discovered on CA plots

18. Conclusions: contd......  However, in some cases, higher soil moisture did not transform into higher maize yields  Higher available soil moisture will reduce the risk of crop failure and therefore contribute to improved livelihood of African smallholder farmers.

19. THANK YOU