Long-term potash application and straw return on yield and soil fertility in intercropped wheat-maize system in Ningxia
IPNI-2010-CHN-NX3
19 Jan 2011
2010 Annual Interpretive Summary
Long-term Potash Application and Straw Return on Yield and Soil Fertility in Intercropped Wheat-Maize in Ningxia, 2010
This fixed-site, intercropped wheat-maize study has been conducted at an alluvial soil site in Yinchuan City in Ningxia Province since 1994. The study is evaluating the long-term agronomic effects of NP and NPK treatments used in combination with straw recycling.
In 2010, after 17 years, the NPK treatment generated 4.8% more grain yield (wheat and maize combined) than the NP treatment. Similarly, NP plus straw produced 5.8% more grain yield than the NP treatment. Use of NPK plus straw produced the highest combined yield of 7,217 kg/ha, which was 10% more than the NP treatment. Soil organic matter has increased by 0.6 to 1.1 g/kg in the treatment receiving straw compared to the NP treatment. Application of K and/or straw increased total soil K by 0.1 to 0.5 g/kg, slow-release K by 57 to 76 mg/kg, and exchangeable K by 40 to 102 mg/kg. Ningxia-2010