耕作与施肥模式对渭北旱塬春玉米土壤肥力和产量的影响

Effects of Tillage Practices and Fertilization Patterns on Soil Nutrients Dynamics and Yield Performance of Spring Maize in Weibei Highland

研究不同保护性耕作模式与施肥模式对春玉米田土壤养分、水分利用效率、养分利用效率、作物产量的影响,筛选适宜的保护性耕作和施肥模式,为渭北旱塬农田培肥、提高水分利用效率和增加玉米产量提供技术支撑。2013-2014年在渭北旱塬开展田间试验,设置农户常规模式（翻耕＋低肥）、现有高效模式（免耕＋高肥）和创新高效模式（深松＋平衡施肥）3种处理,测定玉米播前和收后土壤养分变化,各生育时期、休闲期土壤水分变化和作物产量。结果表明：“深松＋平衡施肥”模式与“免耕＋高肥”模式较“翻耕＋低肥”模式提高土壤0-60cm土层有机质、碱解氮、速效磷和速效钾质量分数,其中0-20cm土层增加显著;2013年“免耕＋高肥”模式对土壤养分增加量较“深松＋平衡施肥”模式高,2014年“深松＋平衡施肥”模式较“免耕＋高肥”模式和“翻耕＋低肥”模式高,在0-20cm土层增加显著。“深松＋平衡施肥”模式较“翻耕＋低肥”模式2a平均增加产量11.23%,土壤水分利用效率提高12.3%,且显著提高氮磷肥利用效率。综合分析表明,“深松＋平衡施肥”模式在增加土壤养分质量分数、提高水分和养分利用效率及增加产量方面优于其他2种模式,是适合渭北旱塬春玉米增产的生产模式。

The objective of this study is to reveal the effects of different conservative tillage practices and fertilization patterns on fertilizer utilization efficiency,WUEand grain yield performance of spring maize,thus to find out a proper tillage-fertilization combination and provide technical supports for enhancing fertilizer utilization efficiency,WUEas well as grain yield performance of spring corn for Weibei Highland.A 2-year field experiment was conducted from 2013 to 2014,three different tillage practices combined with fertilization regimes were set up,namely,conventional farmer pattern（deep ploughing and low fertilization level）,existent highly efficient pattern（no-tillage and high fertilization level）and innovative highly efficient pattern（sub-soiling and moderate fertilization level）,soil nutrient conditions before sowing and after harvesting,soil water dynamics at stage of maize growth and winter fallow as well as grain yield of spring maize were measured and calculated.The results showed that innovative highly efficient pattern and existent highly efficient pattern had higher mass fraction of soil organic matter,available nitrogen,available phosphorus and available potassium from 0-60 cm layers underground compared with conventional farmer pattern,and it was much more obvious in the top 0-20 cm layer.A larger amplitude increment of soil nutrients was respectively observed under existent highly efficient pattern in 2013 and under innovative highly efficient pattern in 2014,and the increments were both significant in top 0-20 cm layers.Compared with conventional farmer pattern,innovative highly efficient pattern enhanced grain yield and WUEby 11.23%and 12.3%respectively,and nitrogen utilization efficiency was also greatly improved.In conclusion,innovative highly efficient pattern is a proper production pattern for Weibei Highland because of its better performance in terms of soil nutrient quality,WUE,fertilizer utilization efficiency and grain yield.