【摘要】 免耕轮作对土壤性质有明显改善作用。在免耕秸秆覆盖基础上进行燕麦、玉米、大豆3种作物轮作2个周期的试验研究。结果表明,免耕秸秆覆盖结合不同作物轮作能调节土壤水热环境,增加土壤速效养分含量。土壤贮水量在不同处理间总体表现为免耕留高茬覆盖(NHS)>免耕留低茬覆盖(NLS)>免耕留高茬(NH)>免耕留低茬(NL)>常规翻耕(T),3种轮作方式中均以燕麦-大豆-玉米方式最高。轮作2个周期后NHS、NLS、NH、NL分别较T土壤贮水量在作物苗期增加了16.24%、12.16%、8.75%、5.56%,可见免耕覆盖能明显提高土壤水分蓄储能力。土壤温度在0~5 cm土层受外界环境影响最大;免耕覆盖在低温时起"保温作用",能提高土壤温度1.4~2.4℃;高温时起"降温作用",能降低土壤温度1.8~3.4℃;秸秆覆盖后土壤温度日变化平缓。同时免耕结合轮作处理能不同程度增加土壤有机质及速效养分含量,说明免耕轮作在该地区能较大程度的改善土壤性质,为提高作物产量提供了基础和有效保证。更多还原

【Abstract】 No tillage with rotation had a significant improvement on soil properties.On the basis of no tillage straw mulching,a two-cycle rotation experiment in three kinds of crops(oat,maize,soybean) was conducted.The results indicated that no tillage straw mulching with crop rotation regulated soil hydrothermal environment and increased soil available nutrients.The soil water storage showed a trend among different treatments as high stubble with mulching(NHS) > low stubble with mulching(NLS) > no tillage with high stubble(NH) > no tillage with low stubble(NL) > conventional tillage(T),and the oatsoybean-maize sequence showed the highest among three kinds of crop rotation sequence.After two rotation cycles,the soil water storage of NHS,NLS,NH and NL was increased by 16.24%,12.16%,8.75% and 5.56% than T in crop seedling stage.It showed that no tillage straw mulching obviously improved the capacity of soil water storage.The temperature of 0 ~ 5cm soil layer was greatly affected by external environment.At a lower temperature level,no tillage straw mulching had a"heating effect"and improved the soil temperature by 1.4 ~ 2.4 ℃.At a higher temperature level,it showed a "cooling effect"and decreased the soil temperature by 1.8 ~ 3.4 ℃.And after the straw mulching,the temperature diurnal variation was gentle.No tillage with rotation increased soil organic matter and available nutrients in different levels,which indicated that no tillage with rotation largely improved soil properties in this area and provided a basis and effective guarantee for the improvement of crop yield.更多还原