Win-win technologies for growing rice and other irrigated crops with less water, and for reducing soil erosion in rainfed areas, were highlighted at the Challenge Program on Water and Food (CPWF) sessions at the International Yellow River Forum. The technologies are win-win for both farmers and the environment.
CONSERVATION AGRICULTURE
Conservation agriculture involves reduced tillage and keeping some crop residues on the soil surface. This increases infiltration of rainfall into the soil profile, and greatly reduces soil erosion by wind and water, and thus sedimentation of the river system from cropped lands. Unproductive evaporation of water from the soil surface is also reduced as a result of reduced soil disturbance and mulching. As a result, there is more water available for the crop in water-short rainfed areas, increasing yields, and reduced irrigation water requirement in irrigated areas. The fertility of the soil also increases due to reduced erosion, retention of crop residues, and reduced breakdown of organic matter through tillage. Farming also becomes much more profitable due to reduced tillage costs, and reduced need for fertilizers, reduced irrigation costs in irrigation areas, while yields increase in water short rainfed situations, and labour requirements are also reduced.
The environment also benefits in many ways including reduced erosion and sedimentation of rivers, reduced greenhouse gas pollution (from tillage and straw burning), reduced air pollution (dust, smoke), increased soil fertility, and reduced extraction of water for irrigation. It truly is a win-win technology.
Across the world, the benefits of conservation agriculture are beginning to be recognized, and it is currently practiced on about 100 million hectares. Much of this is in developed countries such as the USA and Australia, where fields and machinery are large. However there is absolutely no acceptable reason why it cannot be adopted by small farmers, including millions of farmers across the Yellow River Basin. While there are pockets of adoption of conservation agriculture in parts of the Yellow River Basin, especially in the irrigated wheat-maize systems of Shandong province, overall adoption in the Yellow River Basin is almost negligible to date. All that is needed is the political will to make it happen ¨C to assist the development and refinement of machinery suitable for small farmers, and to undertake major programs to disseminate the technology and to facilitate uptake.
The Challenge Program Conservation Agriculture project in China is making good progress in the development and refinement of machinery for the small tractors used by many farmers in the Yellow River Basin. Ultimately, these machines will enable farmers to plant their crops in a single operation, into the residues of the previous crop. However there is still a lot of work to be done to develop and refine the machines and best practices for the different cropping systems, soils and climates across the Yellow River Basin. The project is a collaborative effort between several institutions, machinery companies and farmers in China, together with the International Wheat and Maize Centre in Mexico. This project is focusing its efforts on the bigger challenge of developing conservation agriculture systems for rainfed agriculture in 5 provinces across the Yellow River Basin ¨C Inner Mongolia, Ningxia, Shanxi, Henan and Shandong.
For more information about Conservation Agriculture, please contact any of the principal investigors from the various provinces: Prof. Yan Changrong (Chinese Academy of Agriculture, Beijing yancr@cjac.org.cn), Prof. Yuan Hanmin (Ningxia Academy of Agriculture and Forest, hanminyuan886@hotmail.com), Prof. Zheng Fei (Henan Academy of Agricultural Science, fiezh@371.net), Prof. Gao Huanwen (China Agricultural University, Beijing, ghwbgs@cau.edu.cn), Prof. Wang Fahong (Shandong Academy of Agricultural Science, wheat-cul@163.com, Dr Ken Sayre (CIMMYT, Mexico k.sayre@cgiar.org)
AEROBIC RICE
Aerobic rice is a recently-developed system of growing rice with much less irrigation water (typically 1 to 3 irrigations per crop) than traditional puddled, transplanted, flooded rice cultural systems. The rice is seeded just like wheat, into dry or moist soil. Over the past 15 or so years, China Agriculture University has developed rice varieties capable of producing yields of 5-6 t/ha (333-400 kg/mu) with just one to 3 well-timed irrigations throughout the whole season. While yields are only about half to two thirds those of traditional rice cultural systems, grown with unlimited water, yields are much higher than traditional rice crops which fail badly where there is water shortage. In fact, per unit of water consumed to produce the grain (kg grain/m3 of water), aerobic rice is much more efficient than traditional rice culture. Thus aerobic rice provides the opportunity to continue to grow rice where there is no longer enough water for traditional rice growing methods, such as around Beijing. There is tremendous potential to continue to grow rice using less much less irrigation water through adoption of aerobic rice in major parts of both the rice growing areas and traditional non-rice (maize, soybean) areas of the Yellow River Basin. In comparison with upland crops like maize, aerobic rice has the additional advantage of being tolerant to waterlogging, whereas untimely waterlogging can cause failure of crops like maize.
For more information contact Prof. Wang Huaqi (China Agricultural University, Beijing wanghuaqi@cau.edu.cn or caurice@263.net), Dr Bas Bouman (IRRI, Philippines, b.bouman@cgiar.org)
The CPWF workshop at the IYRF was organized by Ms Sun Feng, CPWF Yellow River Benchmark Basin Coordinator and Division Director of the International Cooperation of the YRCC, together with Ms Dong Wu of the YRCC Information Centre.
Source:YRCC |
