辽西旱农区深层水肥调控对土壤主要物理性质和玉米产量的影响

Effects of deep moisture and fertility regulation on main physical properties of soil and yield of maize in dryland regions in western Liaoning Province

针对辽西旱农区耕地土壤存在的＂旱、薄、瘦＂问题,进行了机械化秸秆深还和化肥深施试验以及翌年免耕种植玉米的组合技术试验。结果表明：（1）处理间表层（0~10 cm）容重变幅均在1.25~1.27 g.cm-3之间,土层10~20 cm处理之间差异明显,对照区容重1.55~1.57 g.cm-3,秸秆深还和化肥深施处理土壤容重大幅降低,秸秆深还处理秸秆集中的层次（20~30 cm）土壤容重在1.2 g.cm-3以下,且比较稳定。（2）试验的第一年,秸秆深还和化肥深施处理的土壤含水量随耕深的增加而上升,到20~30 cm土层秸秆深还处理由于秸秆吸水而土壤含水量陡然降至11.45%,翌年干旱的情况下,降水量由193.9 mm下降到35.1 mm,对照区各层次土壤含水量明显低于其他两种处理,秸秆集中层次的土壤含水量仍保持在16.39%。（3）2010年秸秆深还和化肥深施处理的玉米平均产量分别达到13 094.3 kg.hm-2和12 782.66 kg.hm-2,分别比传统耕作增产9.04%和6.44%。2011年全年的降水量比上一年减少了158.8 mm,两项新技术的玉米平均产量仍能保持在12 053.10 kg.hm-2和11 523.45 kg.hm-2,分别比传统耕作增产9.64%和4.82%。由此可以看出,两项技术具有松土扩容功能、深层蓄水的缓冲功能、御旱增产功能。

In view of the problems of drought, shallow plough layer and low fertility in the arable soil of dryland re- gions in western Liaoning Province, the experiment of integrated technologies of mechanized deep straw placement, deep fertilizer application and no-till planting of maize were carried out. The results showed that： （1） The variation range of bulk density of surface soil under deep straw placement and deep fertilizer application was 1.25 ~ 1.27 g＂ cm- 3, and there was a significant difference among the treatments in the soil layer of 10 ~ 20 cm, while the soil bulk density of the control was 1.55 ~ 1.57 g＇ cm- 3. The soil bulk density in the layer with centralized straw placement was lower than 1.2 g＇cm-3 and more stable. （2） The soil water content in 2010 increased with the increment of tillage depth under deep straw placement and deep fertilizer application, but it suddenly decreased to 11.45 % in 20 - 30cm soil layer under deep straw placement due to the water absorption of straw. In 2011 when the rainfall reduced from 193.9 mm to 35.1 ram, the soil water content in all layers under these two treatments was higher than that under the control, and in straw concentra- tion layer it still remained at 16.39%. （3） In 2010, the average yield of maize was 13 094.3 kg＇hm-2 and 12 782.55 kg＂ hm- 2 under deep straw placement and deep fertilizer application respectively, being increased by 9.04 % and 6.44 % respectively compared with that under the control. In 2011, although the annual rainfall was 158.8 rmn lower than that in 2010, the average yield of maize could still reached at 12 053. 10 kg· hm-2 and 11 523.45 kg· hm-2 respectively under these two new technologies, with a increase rate of 9.64 % and 4.82 % respectively compared with that under the con-trol. te of 9.64% and 4.82% respectively compared with that under the control.