秸秆覆盖量对半干旱区旱作春玉米生长及水分利用效率的影响

在宁夏南部旱作农田,连续2年进行了0 kg/hm2(对照)、4 500、9 000和13 500 kg/hm24种不同秸秆覆盖量处理的栽培试验。结果表明,随着覆盖量的增加,在播种45 d后春玉米的株高、茎粗、叶面积等农艺性状观测值均随着明显提高,当覆盖量为13 500 kg/hm2时,平均比对照分别提高32.8%、48.4%和39.1%。当覆盖量为9 000 kg/hm2时,玉米的产量和水分利用效率分别较对照提高了16.2%和27.3%。当覆盖量大于9 000 kg/hm2时,其增产保墒效果不再明显提高。

Effects of Straw Mulching Quantity on Growth and Water Use Efficiency of Dry Farming Spring Maize in Semiarid Areas

Cultivation experiments of four different straw mulch quantities of 0 kg/hm~2、4 500 kg/hm~2、9 000 kg/hm~2 and 13 500 kg/hm~2 are conducted in the dry farmlands of Southern Ningxia for two successive years.Results show that with the increasing of straw cover amount,observed values of agronomic characters of plant height,stem diameter and leaf areas of spring maize are improved obviously 45 days later after sowing compared with control group.When straw mulch amount is 13 500 kg/hm~2,the values are improved respectively by 32.8%,48.4% and 39.1% on average.When 9 000 kg/hm~2,the output and water use efficiency of spring maize is increased by 16.2% and 27.3%.When straw mulch amount is greater than 9 000 kg/hm~2 ,effect of water conservation and yield increase is no longer enhanced significantly.