1. Rice and the environment Crop and Environmental Sciences Division International Rice Research Institute Los Baños, Philippines

2. RICE: most important staple food in Asia Annually 550-600 million ton => 3 billion people

3. Floatingrice Deepwater Deepwater Rainfed lowland Rainfed lowlandDrought/ flash floods Irrigated Irrigated Upland rice Rice ecosystems Rice is unique in its ability to grow in a wide range of hydrologic environments, some of which where other crops can not grow

4. Irrigated lowland rice (paddy)

5. Lowland rice

6. Upland rice

7. Floodprone rice

8. Rice production in Asia

9. Area (10 6 ha) Production (%/10 6 ton) Yield (t ha -1 ) Irrigated Lowland 7975%3-9 Rainfed lowland 5419%2.3 Upland144%1 Deepwater11 (overlap) 2% 1.5 Salt- affected 9-12 (overlap) 1 Total150550-600 Rice environments and production

10. World rice production and price

11. Irrigated lowland rice (“paddy”): Land soaking Puddling Levelling Bunded fields Transplanted or direct seeded “Permanently” flooded

12. Soaking and puddling

13. Puddling

15. Land levelling

16. Bund construction

17. Seed bed in main field

19. Ready for transplanting

20. Transplanting

21. Just transplanted fields

22. Direct (wet) seeding

23. Direct (wet) seeding using drum seeder

24. Wet-seeded rice

25. Lowland rice landscape

27. Where does all the water come from?

28. Main reservoir

29. Spilling

30. Water tunnels

31. “Natural” main canal

32. Lined main canal

33. Water control

34. Aquaduct

35. Water distribution

36. Smaller and smaller canals…

37. Finally at farmers’ fields

38. Plot-to-plot irrigation after water gets delivered to farmers

39. Scooping water

40. Smaller scale: pumping from canals, creeks,..

41. Pumping from small reservoirs to store water

42. Millions of Asian farmers now use shallow tubewells to pump from groundwater

43. Harvest time: Finally dry land

44. Environment and ecosystem services

45. Irrigated lowland rice 75% of the world’s rice production Highly sustainable in terms of yield Environmental impacts (traditional systems): Ecosystem services: fish, snails, groundwater recharge, flood buffer, biodiversity, temperature buffer, prevent soil erosion and landslides, cultural aspects,.. Methane (3-6% globally) Ammonia volatilization (acid rain) Little N 2 O Danger chemical outflow in surface water No/little Nitrate leaching Pesticides degrade rapidly Low herbicide use Raise groundwater table => risk salinization Efficient to leach salts Acts as wetland in removing N and P

46. Fish in irrigation ponds Ducks Fish in irrigation canals Food production: fish and ducks

47. Lowland rice landscape: specific biodiversity?

48. Mountain terraces Ground water recharge Mitigate erosion Mitigate run-off, floods

49. Steve McCurry, 1988.  Steve McCurry, 1988. Deltas: flood buffer with production potential