玉米秸秆不同还田方式对黑土肥力特征的影响

Effect of Different Maize Straw-returning Modes on the Fertility of Black Soil

通过4年田间定位试验,研究均匀垄与宽窄行种植模式下玉米秸秆不同还田方式对黑土肥力特征与玉米产量的影响。结果表明,在均匀垄与宽窄行种植模式下,玉米秸秆深翻还田能明显降低耕层（0-20 cm）的土壤容重,增加相应的土壤含水量,提高土壤有机质与速效氮、速效钾含量。对亚耕层（21-40 cm）土壤的培育作用更为突出,与无秸秆还田处理相比,秸秆深翻还田使亚耕层土壤容重分别下降6.8%和10.2%,土壤有机质含量分别增加20.1%和14.2%,速效氮含量分别增加12.2%和12.3%,速效钾含量分别增加20.0%和22.0%。秸秆覆盖还田显著增加耕层的土壤有机质与速效氮含量,对亚耕层土壤肥力特征的影响不明显。在两种植模式下,秸秆不同还田方式玉米产量均表现为秸秆深翻〉无秸秆还田〉秸秆覆盖。在东北黑土区,玉米秸秆深翻还田措施能够有效提升土壤肥力,实现玉米的稳产与增产。

Four years field experiments were conducted to evaluate the fertility of black soil and maize yield asaffected by different straw-returning treatments. The results indicated that MBR treatment caused the decline of soilbulk density, and increase in soil water content, soil organic matter content and available N, K content at the uppersoil layer（0-20 cm） under the two planting patterns. Compared with that of CK, soil bulk density at the lower soil lay-er（21-40 cm） were decreased by 6.8% and 10.2%in MBR treatment under conventional row pattern and wide-nar-row row pattern, respectively, moreover, organic matter content, available N content, and available K content at thelower soil layer were increased by20.1%,12.2%, and 20.0% in MBR treatment under conventional row pattern, andsimilarly, were increased by 14.2%, 12.3%, and 22.0% underwide-narrow row pattern. SCR treatment noticeably in-creased organic matter and available N contents at the upper soil layer, however, no significant change was found inother soil properties. The decrease order of the average yield of maize in different treatments was MBRCKSCR.Therefore, application of maize straw returning with moldboard plowing was an effective measure to improve soil fer-tility and produce a higher yield in the Northeast of China.